The Thomist 87 (2023): 1-42

PUNISHMENT AS MEDICINE
IN THE THOUGHT OF ST. THOMAS AQUINAS
SR. ELINOR GARDNER, O.P.
University of Dallas
Irving, Texas

A man who is unjust, is thoroughly miserable,
the more so if he doesn’t get his due punishment
for the wrongdoing he commits.
(Plato, Gorgias 472e)
He wounds as he heals. (Job 5:18)

I

N 1953, POPE PIUS XII addressed a gathering of Italian
jurists in Rome, observing that “most modern theories of
penal law explain punishment and justify it in the last resort
as a protective measure.”1 This deterrent function, along with
attempts to reform, he said, fail adequately to explain punishment, the ultimate purpose of which “must be sought on a
higher plane,” namely, the restoration of that order which has
been upset in the commission of a crime. Only “this more
profound understanding of punishment” can get us “to the
heart of the matter,” to the sacredness of the law itself, “so that
whoever breaks it is punishable and will be punished.”2
Pius XII was responding to a type of humanist thinking
about punishment in vogue in the first half of the twentieth
century.3 Philosopher Michael Davis notes that in the 1960s,
1

The English translation of the address, given in French, is from chapter 30 of Major
Addresses of Pope Pius XII, ed. Vincent A. Yzermans, vol. 1, Selected Addresses (St. Paul,
Minn.: North Central Publishing, 1961), 255.
2
Ibid., 256.
3
This type of thinking is connected to legal positivism, which Pius also critiques in
his address. The classical statement of legal positivism in this period is that of H. L. A.
1

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SR. ELINOR GARDNER, O.P.

the kind of theories critiqued by Pope Pius, C. S. Lewis,4 and
others suffered a “long and steep decline.”5 In the 1970s,
“preventive theories of punishment” gave place to various forms
of what came to be called “retributivism.”6 In the United States,
this revival of interest in the retributive meaning of punishment
was legal as well as philosophical, being reflected in debates
following the 1972 and 1976 Supreme Court decisions on the
punishment of death.7 Retributivists maintain that the defining
feature of punishment is that it gives to wrongdoers something
that they deserve because of a prior wrong.8 It is desert that
justifies the infliction of harm on another person, which
punishment necessarily involves. In response to retributivist
arguments, others maintain that retribution does not define or
justify punishment, and that harming another by punishing him
can only be justified by looking to some good effect or effects to
Hart (The Concept of Law [Oxford: Clarendon Press, {1961} 1994]). The humanitarian
theory has by no means died out, though its proponents now have to respond to the
objections of the new retributivism. Consequentialist justifications of punishment still
abound, and one can still find arguments, as in a 2005 book by American legal scholar
Deirdre Golash, that we would be better off without the “institution” of punishment
(The Case against Punishment: Retribution, Crime Prevention, and the Law [New York:
NYU Press, 2005], 152). The “moral education theory of punishment” in the earlier
work of Jean Hampton is another alternative to retributivism; Hampton suggests that
the goal of educating the offender and the public at large about the moral wrongness of
certain acts provides “a complete justification of punishment” (“The Moral Education
Theory of Punishment,” Philosophy and Public Affairs 13 [1984]: 209).
4
C. S. Lewis, “The Humanitarian Theory of Punishment,” The Churchman 73, no. 2
(1959): 55-60.
5
Michael Davis, “Punishment’s Golden Half Century,” Journal of Ethics 13 (2009):
74.
6
Ibid., 74. See also Michael Moore, Placing Blame: A Theory of the Criminal Law
(New York: Oxford University Press, 1997), 83.
7
Furman v. Georgia (1972) declared capital punishment to violate the 8th and 14th
amendments, prohibiting cruel and unusual punishment. Gregg v. Georgia (1976)
mitigated this judgment by ruling that the punishment of death did not necessarily
violate the Constitution. See the article by Hugo Adam Bedau (modified by the ACLU),
“The Case against the Death Penalty,” https://www.aclu.org/other/case-against-deathpenalty.
8
See Davis, “Punishment’s Golden Half Century,” 74; and Peter K. Koritansky,
Thomas Aquinas and the Philosophy of Punishment (Washington, D.C.: The Catholic
University of America Press, 2012), chaps. 1-2.

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3

be achieved through the punishment (the “nonretributivist”
position). Although, as we will see, twentieth-century retributivism differs in important respects from classical accounts of
punishment, its proponents often look to that tradition for support, and some of them find in Thomas Aquinas a compelling
defense of just retribution. But is Thomas a retributivist?
Although it would be a mistake to examine Thomas’s
thought on punishment exclusively within the bounds of the
contemporary categories (retributivist vs. nonretributivist), we
begin there in order to highlight the present relevance of this
study, and to see exactly where and why Thomas does not “fit
in” to the contemporary dialogue, in order that we may better
know the contours of his account and at the same time realize
what contemporary explanations of punishment tend to omit.
Ultimately we want to know what is the right way for a
Christian to think about punishments: should we desire them as
good, or should we look at them as necessary but unfortunate
features of life, to be chosen only as far as is necessary to
preserve the good order of society?
In light of this general goal, this paper has three specific
aims. It aims to show, first, that Thomas’s account of punishment is better described as “medicinal” than “retributivist,” and,
second, that a correct understanding of the medicinal character
of human punishments requires reference to the revealed truth
of divine retribution. Finally, through these clarifications of the
Thomistic account of punishment, the third aim of this paper is
to highlight what is lacking in the contemporary debates, and
thereby contribute to a more Christian view of the phenomenon
of punishment.
We will begin with an analysis of contemporary retributivism
to pose the “retribution or medicine” question, after which we
will turn to Thomas’s own account of punishment. After considering some difficulties with the use of “punishment” as a
translation of poena, we will consider how Thomas defines this
phenomenon, and the various ways in which it resembles medicine. This will bring us to the theological perspective, which I
will argue is essential to understanding medicinal human

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SR. ELINOR GARDNER, O.P.

punishment. We will then be in a position to see more clearly
the difficulty in calling Thomas a “retributivist,” why the
medicinal characterization better fits his account, and what this
account has to offer the contemporary debate.
I. THE NEW RETRIBUTIVISM
In the second half of the twentieth century, a lively debate
between “retributivists”9 and “nonretributivists”10 flourished in
Anglo-American philosophical literature.11 H. L. A. Hart,
probably the foremost twentieth-century defender of legal
positivism, says that retributivist theories characteristically
“[deny] that the practice of a system of punishment is justified
by its beneficial consequences and claim instead that the main
justification of the practice lies in the fact that . . . the
application to the offender of the pain of punishment is itself a
thing of value.”12 Michael Moore, a proponent of retributivism,
describes it as “a very straightforward theory of punishment,”
which maintains that “We are justified in punishing because and
only because offenders deserve it. Moral responsibility (‘desert’)

9

Some of the more influential retributivist arguments in the period in question are
those of Herbert Morris (see his “Persons and Punishment,” The Monist 52 [1968]:
475-501), Jeffrie Murphy (“Marxism and Retribution,” Philosophy and Public Affairs 2
[1973]: 217-43), George Sher (Desert [Princeton: Princeton University Press, 1989]),
and Michael Moore (Placing Blame).
10
Since nonretributivists look to some good external to punishment to justify the
practice, their view has also been called “externalist,” in contrast to those who justify
punishment by something internal to the act of punishing, the “internalists.” These are
the terms favored by Davis (“Punishment’s Golden Half-Century,” 74) and Anthony
Ellis (The Philosophy of Punishment [Charlottesville, Va.: Imprint Academic, 2012],
chap. 1).
11
See Davis, “Punishment’s Golden Half-Century,” 74.
12
H. L. A. Hart, “Prolegomenon to the Principles of Punishment,” Proceedings of the
Aristotelian Society, n.s. 60 (1959-60): 8. There is a close connection between legal
positivism (the view that “law is a social construction”) and antiretributivism, which
justifies punishment only by its positive social consequences (Leslie Green,
“Introduction,” in H. L. A. Hart, The Concept of Law, 3rd ed. [Oxford: Oxford
University Press, 2012]). The connection is present in the thought of Jeremy Bentham,
the modern originator of both theses.

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5

in such a view is not only necessary for justified punishment, it
is also sufficient.”13
Retributivists, while focusing on desert as the central and
justifying characteristic of punishment, do not necessarily exclude from consideration other goods to be achieved through
punishment. Even Kant, well-known for maintaining that “only
the law of retribution (ius talionis) . . . can specify definitely the
quality and the quantity of punishment,” does not rule out the
desirability of achieving other goods through such punishment.14 A punishment “can never be inflicted merely as a means
to promote some other good for the criminal himself or for civil
society,” he says, but one may still hope and intend to achieve
such goods as well as to satisfy the “Law of Retribution.”15
Perhaps not for Kant, but for some retributivists, goods such as
reform and deterrence could even form part of the determination of punishment itself. For such thinkers, retribution is a
necessary but not a sufficient criterion for justified punishment.
We can call this view moderate retributivism.
A retributivist is expected to offer an “answer to the question
of why offenders deserve to suffer.”16 One way to answer this,
found in such thinkers as Herbert Morris, George Sher, and
John Finnis, is that offenders deserve to suffer because this
suffering removes an advantage they have unfairly gained
through their wrongs. This is not the material gain (if any) of
their crimes, but some internal (psychological or ontological)
benefit gained in the very wrongdoing itself, such as freedom
from self-restraint. Punishment restores equality by counteracting this freedom, giving to the offender something which he
does not want and thereby restoring the balance of social

13

Moore, Placing Blame, 91.
Immanuel Kant, Metaphysics of Morals, rev. ed., trans. Mary Gregor (Cambridge:
Cambridge University Press, 2017), 115.
15
Ibid., 114. I am obliged to an anonymous reviewer for this point about Kant.
16
See Ellis, Philosophy of Punishment, 62: “The Simple Desert Theory refuses a
substantive answer to the question why offenders deserve to suffer” because it takes it as
a self-evident first principle.
14

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SR. ELINOR GARDNER, O.P.

“benefits and burdens” disrupted by the crime.17 Certain
passages in Thomas seem to confirm such a way of looking at
punishment, for example in his answer to the question of
whether one of the effects of sin is the “debt” of punishment
(reatus poenae).18 In his affirmative answer, Thomas compares
punishment to natural phenomena in which we observe one
contrary react against another. In a similar way, when a human
being acts inordinately (i.e., sins), the order against which he
acts responds with a contrary action (punishment).19 In a later
question in the Secunda pars, Thomas asks about the goodness
of vengeance (vindicatio), and here he seems to hold as a practical first principle poena debetur peccato (“punishment is due
to sin”).20
The proponents of nonretributive justifications of punishment, on the other hand, do not think that punishment is justified because it is the correct response to a wrong committed,
but rather because it produces certain positive effects, whether
these effects are individual, communal, or some combination of
the two. Not all nonretributivists go so far as Jeremy Bentham
to say that “all punishment is in itself evil,” but they generally
agree with the conclusion Bentham draws: “[punishment] ought
only to be admitted in as far as it promises to exclude some
greater evil.”21 Contemporary proponents offer many variations
17
Ellis, Philosophy of Punishment, chap. 3. See also Morris, “Persons and
Punishment”; and John Finnis, “Retribution: Punishment’s Formative Aim,” American
Journal of Jurisprudence 44 (1999): 91-103.
18
STh I-II, q. 87, a. 1. References to the Summa are to Summa Theologiae (Ottawa,
Canada: Commissio Piana, 1941), which includes corrections based on the Leonine
edition. Translations of Thomas are my own, except where noted.
19
Ibid. This passage will be considered in detail further on.
20
STh II-II, q. 108, a. 4, s.c. The fact that no authority is cited in this sed contra
seems to support the conclusion that this is a first principle evident to reason, which can
be elaborated and commented upon, but cannot be demonstrated, having the evident
character of a first principle. See also De Malo, q. 4, a. 5, where to help him explain the
will as the subject of original sin, Thomas says simply that it is “manifest” that sin is
something which carries the debt of punishment (“Manifestum est autem quod
peccatum, secundum quod nunc de peccato loquimur, est cui debetur pena”;
Quaestiones disputatae de malo [Rome: Commissio Leonina, 1982], 23:118, ll. 52-54).
21
Jeremy Bentham, The Principles and Morals of Legislation (New York: Hafner
Publishing, 1948), XIII.ii.

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7

on this theme, but their arguments for the most part can be
reduced to the following form: if an institution contributes to
the general happiness of society, then it is justified. Punishment
contributes to the general happiness and hence it is justified.22
The nonretributivist maintains that the only way to justify punishment, since it involves harming another human being, is
some good to be achieved through punishing. Such seems to be
the thinking also in the following response which Thomas
makes to the question of foregoing spiritual goods on account
of scandal:
The infliction of punishments is not sought for its own sake [propter se], but
punishments are inflicted like medicines for restraining sins [ad cohibendum
peccata]. And therefore they have the character of justice [ratio iustitiae]
insofar as sins are restrained through them. But if it were manifest that more
and greater sins would follow the infliction of punishments, then the infliction
of punishments will not be included under justice.23

In other words, punishment does not justify itself; it must be
justified by its effects in “restraining sins.” Nor is this an
isolated instance; Thomas frequently refers to the medicinal
character of punishment, as we will see below, as the consideration that drives the selection of punishment, and even the
choice of whether or not to punish in a particular instance.
How then should we classify Thomas’s account of
punishment? He affirms the notion that punishment is due to
sin, which for him seems to have the character of a first
22

Some contemporary examples may be found in S. I. Benn (“An Approach to the
Problems of Punishment,” Philosophy 33 [1958]: 325-41), David Boonin (The Problem
of Punishment [Cambridge: Cambridge University Press, 2008]), Michael J. Zimmerman
(The Immorality of Punishment [Peterborough, Ontario: Broadview Press, 2011]). Ellis
offers a justification of punishment as a form of self-defense, noting that “the general
prohibition on deliberately harming others can be overridden in cases of self-defence”
(Philosophy of Punishment, 136) Why they can be so overridden “is a surprisingly
difficult question,” he admits (ibid., 137), but his reasoning is basically utilitarian,
revolving around analysis of the costs and benefits of punishment as a social institution.
He takes it for granted that some sort of cost-benefit analysis is the basis of human
motivation (ibid., 154).
23
STh II-II, q. 43, a. 7, ad 1.

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SR. ELINOR GARDNER, O.P.

principle, and he thinks that to punish is (or may be) an act of
justice. This would seem to make him a retributivist. With the
nonretributivists, on the other hand, Thomas looks to the effects of punishment on the common good, not only as an
addition to the retributive goodness already present in the
chosen punishment, but as the very thing that justifies the
choice of that particular punishment.24 The resolution of this
puzzle will require us eventually to abandon the retributive/
nonretributive framework, but before we do so, we should look
at the most promising way of resolving it within that
framework.
II. THOMAS AQUINAS, RETRIBUTIVIST?
While there are many representatives of what we have called
moderate retributivism, John Finnis has an account that is of
particular importance for our purposes, both because of its
clarity and insight and as an interpretation of Thomas. Finnis
argues that retribution is the essence of punishment, its
“formative aim.”25 According to Finnis, in punishment a
wrongdoer suffers something contrary to his will, and in so
suffering he loses the benefit he illicitly gained when he indulged his will to excess in doing the wrong.26 Whether or not
any good effects follow from punishment, Finnis argues, it has
at least this good aspect, that “punishment ‘sets in order’ the
24

I have simplified the classification of contemporary theories in order to bring out
the aporia. One should also note the so-called “expressive theory of punishment”
advocated in Hampton’s work. Hampton first posits the moral education theory as an
alternative to retributivism, but in later developments embraces the designation
“retributivist.” See Richard Dagger, “Jean Hampton’s Theory of Punishment: A Critical
Appreciation,” APA Newsletter on Philosophy and Law 10, no. 2 (2011): 6-11.
25
The title of Finnis’s most complete discussion of punishment is “Retribution:
Punishment’s Formative Aim.” His earlier treatment (“The Restoration of Retribution”
Analysis 32, no. 4 [1972]: 131-35) contains some elements of his later account, which is
reiterated more concisely, but with no substantial change, in his book Aquinas: Moral,
Political, and Legal Theory (New York: Oxford University Press, 1998): 210-18.
26
This profit or advantage is principally an immaterial one, that of indulging one’s
own will, rather than a material advantage that may or may not be achieved in any given
wrongful act (Finnis, “Retribution,” 102).

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guilt whose essence was wrongful willing.”27 Punishment “sets
in order” or reestablishes equality by “cancelling the wrongdoer’s unfair profit.”28 But how does punishing someone heal
disorder? Finnis explains:
The precise benefit or advantage whose fair distribution it is the primary and
shaping purpose of punishment to uphold is the advantage of freedom, in
one’s choosing and acting, from external constraints including the constraints
appropriately imposed by laws made for the common good.29

This reaffirms Finnis’s assertion in an earlier work that
What the criminal gains . . . is the advantage of indulging a (wrongful) selfpreference, of permitting himself an excessive freedom in choosing . . . being
something that his law-abiding fellow-citizens have denied themselves insofar
as they have chosen to conform their will (habits and choices) to the law even
when they would “prefer” not to.30

With regard to “the ‘medicinal’ or ‘healing’ point of punishment, of which Aquinas often speaks,” Finnis argues that it
includes retribution.31 In other words, retribution is medicine
applied to the community as a whole, removing the extra
27

Ibid., 99.
Ibid., 102.
29
Ibid., 101. This same view can be seen in an earlier book, where Finnis says that
“the defining and essential . . . point of punishment is to restore an order of fairness
which was disrupted by the criminal’s criminal act. That order was a fairly (it is
supposed) distributed set of advantages and disadvantages, the system of benefits and
burdens of life in a human community” (John Finnis, Fundamentals of Ethics
[Washington, D.C.: Georgetown University Press, 1983], 128).
30
Finnis, “Restoration of Retribution,” 132.
31
“When he speaks of punishment’s medicinal function, Aquinas has in mind not
only reform and deterrence and restraint and coercive inducement to decent conduct,
but also the function [of] . . . redressing of the disorder caused by the offense. Why is
this medicinal, curative healing? Because it is the healing of a disorder—precisely an
unjust equality—introduced into a whole community by the wrongdoer’s criminal
choice and action” (Finnis: “Retribution,” 97). Finnis adds that for Thomas “this
(re)ordering [ordinativa] point of punishment can either be accounted remedial
[medicinalis], or contrasted . . . with the remedial (deterrent, reformative),” depending
on the context (ibid., 99).
28

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“freedom in choosing” that the wrongdoer gained by causing
him to suffer something opposed to his will.
Peter Karl Koritansky rightly questions this explanation of
retribution’s medicinal character in itself and as an interpretation of Thomas. He points out that the language of
“benefits and burdens” arises from a contractarian view of
political society.32 In this view, binding oneself to obey the civil
law is limiting one’s freedom. Citizens willingly accept such
limits and bear the “burden” of obeying the laws, for the sake of
the many benefits that accrue to them when a great number of
persons do likewise. The criminal, on the other hand, grasps for
the “benefit” of acting precisely as he wishes, regardless of the
law. As Koritansky argues at some length,33 proponents of the
“benefits and burdens” view of punishment have a hard time
explaining how exactly criminal action is advantageous to the
criminal, apart from any material gain he may accrue (which is a
matter for restitution and is not the issue in punishment).34
Further, it is hard to accept Finnis’s account as a reading of
Thomas, for whom obedience is a virtue and sin a deficiency or
loss. True, the criminal may see obedience as burdensome, but
as Aristotle says, “in all such cases it seems that what is really so
is what appears so to the excellent person.”35 When we accept
the notion that in following the law good citizens are somehow
“losing out,” we seem to affirm the disordered perception of the
criminal, rather than correcting it. (Compare Socrates’s
comment to Gorgias, cited in the epigraph to this essay.) As
Koritansky puts it, for Thomas, “Criminals are, on the contrary,
supremely disadvantaged by their criminal actions which,
32

Koritansky, Thomas Aquinas and the Philosophy of Punishment. Koritansky
develops his thesis in a number of shorter pieces, most recently in “Retributive Justice
and Natural Law” The Thomist 83 (2019): 407-35.
33
Koritansky, Thomas Aquinas and the Philosophy of Punishment, chap. 2.
34
Thomas grants that one can speak in terms of profit (lucrum) and loss (damnum)
about all matters of justice, but these names, which belong properly to matters of buying
and selling, are used improperly or metaphorically about other matters of justice; see
STh II-II, q. 58, a. 11, ad 3. Perhaps the idea of a benefit in freedom gained through
wrongdoing takes the metaphor too literally.
35
Aristotle, Nicomachean Ethics 10.5.1176a16 (trans. Terence Irwin, 2nd ed.
[Indianapolis, Ind.: Hackett, 1999], 161).

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precisely because they fly in the face of one’s natural inclination
to serve and promote the political common good, make those
who perform them into a worse person.”36 Thomas, as we will
see below, does affirm that punishment heals the disorder
introduced by wrongdoing, but in his view it does so by
removing, not a benefit, but a diseased excess.37
Despite these limitations, Finnis puts us on the right track in
suggesting that for Thomas all punishment is both retributive
and medicinal. If retribution provides the very form of penal
acts, then we need not ask whether punishment is or should be
retributive. If it is not retributive, it is not punishment. If, in
turn, retribution is itself medicinal, then all punishment is also
in some way therapeutic or healing. Retribution and healing,
then, are not two different goals, but two aspects of the same
goal. Finnis’s insight into the unity of retribution and medicine
will prove helpful in interpreting Thomas’s account of
punishment, to which we now turn.

36

Koritansky, Thomas Aquinas and the Philosophy of Punishment, 150. Finnis’s own
illustration in “Retribution” highlights the problem. In the “incident on hill 102,”
Private Eriksson was not disturbed because he thought that he had lost something that
his comrades had gained. A good man does not consider it a “benefit” to be able to rape
and murder, nor does he consider himself as losing or giving up something in restraining
himself from doing such acts. On the contrary, he perceives those actions as they truly
are, denigrations.
37
In Hampton’s “moral education theory of punishment,” retribution is replaced
with the idea “that punishment is intended as a way of teaching the wrongdoer [and the
community in general] that the action she did (or wants to do) is forbidden because it is
morally wrong and should not be done for that reason” (Hampton, “Moral Education
Theory of Punishment,” 212). If “education” is understood broadly enough (i.e., not as
merely imparting information, but as moral formation), then it could be taken as
equivalent to the goal of healing, in which case the same response may be made that
“education” and “retribution” are not so much two different goals to be achieved in
punishing, but two different aspects of (or views on) the same goal. The criminal being
punished by the state, for example, naturally sees his punishment as the state’s infliction
of a painful thing on him in response to his crime, while those inflicting the punishment
may see it in light of education/healing.

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SR. ELINOR GARDNER, O.P.

III. MALUM, CULPA, POENA—EVIL, FAULT, PUNISHMENT
As we turn to a closer examination of Thomas’s discussion of
punishment, it will be helpful to clarify some terms, first and
most fundamentally the term “punishment” itself, which is a
traditional but not unproblematic translation of Thomas’s
poena. Thomas consistently uses the terms poena and culpa to
describe evil or defects found in a rational nature. Malum—
usually translated “evil” but perhaps more accurately “defect”
or “badness”—refers most broadly to any “privation of a form
or ordering or proper measure, whether in a subject or in an
act.”38 When the defect is “natural” (e.g., blindness or lameness), Thomas calls it simply malum, but when the defect is in
an agent’s end-directed action, he calls it peccatum, which “is
said of an act lacking its proper ordering or form or measure,”39
that is, when an agent acts but does not attain the end for which
he acts.40 We do not have a single word in English for this
concept of “defective action”; the traditional but misleading
translation is “sin.”41 “Sin” is misleading because we do not
normally refer, for example, to the error of a grammarian in
writing42 as a “sin,” even though it too is a voluntary act failing
to attain its end. Culpa, often translated as “fault,”43 but also

38
De Malo, q. 2, a. 2 (Leonine ed., 23:33, ll. 125-28): “Nam malum communius est:
in quocumque enim, siue in subiecto siue in actu, priuatio forme aut ordinis aut mensure
debite mali rationem habet.”
39
Ibid. (Leonine ed., 23:33, ll. 128-30): “Set peccatum dicitur aliquis actus debito
ordine aut forma siue mensura carens.”
40
De Malo, q. 3, a. 1 (Leonine ed., 23:66, ll. 132-35): “That something is called a
sin, insofar as it is found in natural and in artificial things, arises from the fact that
someone in acting does not attain the end for which he acts” (“Peccatum enim
communiter dictum secundum quod in rebus naturalibus et artificialibus inuenitur, ex eo
prouenit quod aliquis in agendo non attingit ad finem propter quem agit”).
41
See Robert Pasnau, review of Thomas Aquinas, On Evil (translations by R. Regan
and J. A. and J. T. Oesterle) in Review of Metaphysics 57 (2004): 599-601. “Defective
action” is the phrase Pasnau uses in his review.
42
De Malo, q. 3, a. 1 (Leonine ed., 23:66, ll. 136-41). See also De Malo, q. 1, a. 5.
43
John and Jean Oesterle’s translation of De Malo (Notre Dame, Ind.: University of
Notre Dame Press, 1995) uses this wording.

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“moral wrong,”44 refers to a voluntary or willed defect in
action, which corresponds more nearly to what we mean by
“sin.”45
The problem, however, seems to be not only a problem of
translation; Thomas himself is aware that there is ambiguity in
the use of peccatum. Were we to be perfectly precise, we would
say “culpa” when we wanted to speak of a moral defect, since
peccatum is a broader term including both moral and nonmoral
defects. This broader meaning of peccatum is rooted in the
classical tradition, but in the Christian tradition it typically
refers to those defects of human persons by which they are
estranged from God.46 Hence in theological contexts, peccatum
often means the same thing as culpa.47 Despite his own clear
distinction between peccatum and culpa, Thomas does not
attempt to impose a more precise usage contrary to the

44
Richard Regan uses this expression in his translation of De Malo (Oxford: Oxford
University Press, 2001).
45
De Malo, q. 2, a. 2 (Leonine ed., 23:33, ll. 134-40): “Any inordinate act
whatsoever can be called a peccatum, whether in nature, or art, or morals. But peccatum
does not have the nature of culpa unless it be voluntary, for nothing is imputed to
someone as a fault except from the fact that it is in his power. And thus it is evident that
peccatum is found in more instances than culpa” (“Quilibet enim actus inordinatus
potest dici peccatum uel nature uel artis uel moris. Set rationem culpe non habet
peccatum nisi ex eo quod est uoluntarium: nulli enim imputatur ad culpam aliquis
inordinatus actus, nisi ex eo quod est in eius potestate. Et sic patet quod peccatum est in
plus quam culpa”).
46
“In pagan antiquity, peccatum (Greek: ἁμαρτία, κακία) has a broad spectrum of
meanings. It can be related to non-ethical error, ethical failures and mistakes, but also to
crimes against the divine world in its broadest sense. In the Jewish and Christian
tradition, peccatum is a core concept with various meanings, which all have to do with a
wrong attitude towards God and His plan with humanity. The term peccatum
represents an attitude of transgression and violation of morality and thus a distancing
from God. Sin causes disorder and disharmony in the relation between God and
humanity, between human beings, and in human beings themselves” (Mathijs
Lamberigts, Augustinus Lexikon Online, ed. Robert Dodaro O.S.A., Cornelius Petrus
Mayer, and Chrisof Müller (Schwabe Verlag), s.v. “peccatum.”
47
In the Vulgate, for example, see Rom 3:20: “per legem enim cognitio peccati”;
Psalm 50(51):4: “a peccato mea munda me”; Gen 4:7: “in foribus peccatum aderit.”

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SR. ELINOR GARDNER, O.P.

tradition, and so he also uses peccatum interchangeably with
culpa, when the distinction itself is not at issue.48
We find a similar situation when we turn to the other side of
malum, that is, to evil which is suffered rather than done.
Besides the evil of culpa, there is another evil proper to rational
or intellectual beings, which Thomas names poena, following
Augustine, who says that “culpa names an evil which we do, but
poena an evil which we suffer.”49 In this sense, poena includes
any evil whatsoever suffered by a rational agent, a much
broader meaning than the English “punishment” or “penalty,”
which typically connotes a civic and even an “artificial” reality
(we will return to this idea later). Yet although poena is broader
than our “punishment,” Thomas understands all suffering, and
not only civil penalties, to be the consequence of sin, and
therefore to be precisely “punishments” in the typical sense.50
To translate poena as “suffering” or “pain” risks obscuring the
relationship between suffering and fault. With this in mind, I
will often leave the term poena untranslated (and likewise culpa,
peccatum, and malum). Where it would not lead to confusion,

48
De Malo, q. 2, a. 2 (Leonine ed., 23:33, ll. 141-42): “according to the usage
common among theologians, one may use peccatum and culpa for the same thing”
(“licet secundum communem usum loquendi apud theologos pro eodem sumantur
peccatum et culpa”
49
Augustine, De lib. arb. I, quoted in De Malo q. 1, a. 4 (Leonine ed., 23:20,
ll. 187-89): “ut patet per Augustinum in I De libero arbitrio, ubi culpam nominat malum
quod agimus, penam uero malum quod patimur.”
50
“According to the Catholic faith, it is to be held without doubt that death and all
similar defects of the present life, are a poena for original sin” (“Absque omni dubio
secundum fidem catholicam tenendum est quod mors et omnes huiusmodi defectus
praesentis uite sunt pena peccati originalis”) (De Malo, q. 5, a. 4 (Leonine ed., 23:137,
ll. 61-64). The text goes on to clarify that some of these poenae are directly inflicted by
God, while others are concomitant effects of the primary poenae. That the
understanding of all the sufferings of human life is a revealed truth is underlined in the
reply to the first objection, where Thomas notes that “Seneca and other pagan
philosophers did not consider [death] as having the nature of poena.” See also q. 1, a. 4
(Leonine ed., 23:20, ll. 138-39), which concludes that the mala found in intellectual
creatures, whether in the soul, the body, or in exterior things, “must be called poenae
according to the understanding of Catholic faith” (“tale malum secundum fidei catholice
sententiam necesse est quod pene dicatur”).

PUNISHMENT AS MEDICINE

15

the traditional translation “punishment” is used, keeping in
view the theological connection to fault.
IV. THE NATURE OF POENA/PUNISHMENT
The Disputed Questions on Evil (De Malo) contain Thomas’s
most comprehensive discussion of poena and culpa.51 Thomas
distinguishes these two kinds of mala by means of three
criteria.52 First, poena is the consequence of culpa.53 Second,
poena is contra voluntatem: contrary to the will of the one
suffering it, while culpa is secundum voluntatem: it proceeds
from the will.54 Third, poena is a passio, that is, something
suffered; while culpa is an action, something done.55
“Poena is inflicted to limit and regulate the badness of
culpa”;56 fault introduces disorder and punishment (re)introduces order.57 Punishment as a response to fault takes the
phenomenon from the agent’s view, rather than the patient’s; it
is in this sense that punishment is a moral act, something
intended.58 Punishing is an act of justice, which consists in
giving another his due. When disorder has been caused by an

51
Parallel discussions of the poena/culpa distinction are found in II Sent., d. 35, q. 1,
a. 1; d. 37, q. 3, a. 2 (Scriptum super Sententiis, ed. Mandonnet and Moos [Paris:
Lethielleux, 1929]); STh I, q. 48, aa. 5-6; and Comp. Theol. I, cc. 119-22 (Leonine ed.
[Rome, 1979], 42:125-26). The distinction made is the same in each place.
52
For a clear presentation of the three criteria, see Koritansky, Thomas Aquinas and
the Philosophy of Punishment, chap. 4.
53
De Malo, q. 1, a. 4 (Leonine ed., 23:20, ll. 140-43). See also ScG III, c. 141
([Rome: Commissio Leonina, 1926], 14:424-25) on the difference and the order of
punishments.
54
De Malo, q. 1, a. 4 (Leonine ed., 23:20, ll. 153-57). See also ScG III, c. 142
(Leonine ed., 14:426-27).
55
De Malo, q. 1, a. 4 (Leonine ed., 23:20, ll. 167-71).
56
De Malo, q. 1, a. 5, ad 7 (Leonine ed., 23:25, ll. 325-26): “set potius e conuerso
ideo infertur malum pene ad cohercendam et ordinandum malitiam culpe.”
57
De Malo, q. 1, a. 4 (Leonine ed., 23:20, ll. 179-81): “ex malo actionis quod est
culpa, sequitur malum agentis quod est pena, diuina prouidentia culpam per penam
ordinante.”
58
See De Malo, q. 1, a. 5, ad 6 (Leonine ed., 23:25, ll. 318-22).

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SR. ELINOR GARDNER, O.P.

offense, the remaining disorder creates a “debt” of punishment
(debitum poenae).59
While Thomas clearly sees poena as something that can be
intended in a virtuous way, he nonetheless classifies it as
malum, insofar as it is a privation, the loss of a good, something
painful to the one suffering it. In this sense, poena is something
evil and hence not willed for its own sake. As pains, poenae are
not willed per se.60 However, poena takes away a good in order
to bring about a greater good, the just order disturbed by
wrongdoing. This good is what is willed per se in choosing to
punish. Punishment, then, like the associated emotion of anger,
has a dual object: a loss to another, an evil, which cannot be
willed for its own sake; and a good, which is willed for its own
sake.61
The second characteristic of poena is its being contra
voluntatem. In his discussion of the evil of poena, Thomas
points out that something may be contrary to someone’s will in
three ways: actually, habitually, or according to natural inclination. Something is contrary to a person’s actual will when he
knowingly endures something contrary to what he wills. For
example, someone is convicted of theft and spends a year in
prison, when he would rather be able to move about freely.
Second, something is contrary to a person’s habitual will when
he is deprived of something that would be contrary to his will,
if he knew about the loss. For example, a son is deprived,
against his habitual will, of his inheritance, even if he does not
actually know of the loss. Third, something is contrary to a
person’s natural inclination when it is contrary to those goods
toward which the human will is inclined by nature, even if it is
59

STh I-II, q. 87, a. 6: “Unde patet quod, cessante actu peccati vel iniuriae illatae,
adhuc remanet debitum poenae.” The alternative phrase Thomas often uses is “reatus
poenae,” as in a. 1 of the same question.
60
V Nic. Ethic., lect. 16: “For poenae are not willed by the lawgiver on their own
account (per se), but like a kind of medicine for sin” (“Non enim poenae sunt per se
intentae a legislatore, sed quasi medicina quaedam peccatorum”) (Sententia libri
Ethicorum, ed. Spiazzi [Turin and Rome: Marietti, 1949], 298b [n. 1089]).
61
On anger as the desire for punishment, see STh II-II, q. 158, a. 2. See also
Nicholas Lombardo, O.P., The Logic of Desire (Washington D.C.: The Catholic
University of America Press, 2010), 66.

PUNISHMENT AS MEDICINE

17

not contrary to the person’s actual or habitual will, as when
“someone who does not will to have virtue is habitually
deprived of virtue, though the natural inclination of his will
tends to the good of virtue.”62 Poena is contrary to the will in at
least one of these three ways. This “contrariness” constitutes the
bitterness of punishment.63
The final characteristic of poena is its being something
received rather than done, a passion rather than an action.
Thomas says that a fault produces a debt of punishment in the
wrongdoer.64 Moral fault, he explains, has two aspects: the
actual wrong committed (actus culpae) and the effect this wrong
leaves in the soul (macula sequens).65 Even when the person is
no longer actually engaged in doing wrong, the disordered state
remains, and this disorder is what poena addresses. Thomas
describes three orders disrupted by a moral fault, to which
correspond three poenae: (1) the internal order of the human
soul under reason (virtue), (2) the order of human society under
designated human beings (familial, civic, ecclesiastical), and (3)
the order of all things under divine providence.66 In the internal
order, a penalty for fault, the prick of conscience (conscientiae
remorsus), follows from knowledge of the fault.67 In the social
order, the punishment is determined and inflicted by human
authorities according to what is customary in the time and
62

De Malo, q. 1, a. 4 (Leonine ed., 23:20, ll. 157-68): “Sciendum tamen est quod
pena tripliciter repugnat uoluntati: quandoque quidem uoluntati actuali, sicut cum quis
se sciente sustinet aliquam penam; quandoque uero est contra uoluntatem habitualem
tantum, sicut cum alicui ignoranti subtrahitur aliquod bonum de quo doleret si sciret;
quandoque uero solum contra naturalem inclinationem uoluntatis, sicut cum quis
priuatur habitu uirtutis qui uirtutem habere non uult, set tamen naturalis inclinatio
uoluntatis est ad bonum uirtutis.”
63
Finnis points out that this is in contrast to the idea of Nietzsche, Bentham, and
others that (physical or exterior) pain itself is the essence of punishment (“Retribution,”
97-98).
64
STh I-II, q. 87, a. 1.
65
STh I-II, q. 87, a. 6.
66
STh I-II, q. 87, a. 1: “Unde secundum tres ordines quibus subditur humana
voluntas, triplici poena potest homo puniri.”
67
Ibid.

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SR. ELINOR GARDNER, O.P.

place,68 inflicting losses either to external or to bodily goods. In
the order of divine providence, there are both temporal and
eternal poenae inflicted by God.69
In summary, “the essence of punishments . . . is that they
subject offenders to something contrary to their wills.”70 In
what sense (or senses) may this same reality be described as
medicine?
V. PUNISHMENT AS MEDICINE
Thomas follows Aristotle71 in describing punishment (both in
the narrow and in the broad senses treated above) with the use
of medicinal imagery. In the discussions of poena in his theological summaries,72 and in the longer discussion in the Disputed
Questions on Evil,73 Thomas is consistent in his use of the
medical analogy that he takes from book II of the Nicomachean
Ethics, where Aristotle says that “virtue has to do with pleasure
and pain . . . [an] indication of [which] is the fact that pain is
the medium of punishment; for punishment is a sort of
medicine, and it is the nature of medicine to work by means of

68

See STh I-II, qq. 95-97, especially q. 97, a. 3, on the change in human law through
custom.
69
ScG III, c. 140 (Leonine ed., 14:422-23); and IV, c. 91 (Leonine ed., 15:284-86).
70
Finnis, “Retribution,” 98. This formula captures all three criteria, since being
“subjected” implies a passion, while “offender” presupposes someone guilty of
intentional wrong (culpa).
71
There have been a number of studies on Aristotle’s use of medical imagery in his
ethical thought. See Werner Jaeger, “Aristotle’s Use of Medicine As Model of Method in
His Ethics,” The Journal of Hellenic Studies 77, part 1 (1957): 54-61; G. E. R. Lloyd,
“The Role of Medical and Biological Analogies in Aristotle’s Ethics,” Phronesis 13
(1968): 68-83; M. Seidler, “The Medical Paradigm in Aristotelian Ethics,” The Thomist
42 (1978): 400-433.
72
II Sent., d. 36, q. 1, a. 3, arg. 3; d. 42, q. 1, a. 2; III Sent., d. 19, q. 1, a. 3, qcla. 2.
STh I-II, q. 87, a. 8; II-II, q. 39, a. 2, ad 1; a. 4, ad 3; q. 43, a. 7, ad 1; q. 66, a. 6, ad 2;
q. 99, a. 4; q. 108, a. 4; ScG III, c. 158; Comp. Theol. I, c. 121, c. 172. In many of these
places, Thomas does not cite Aristotle by name, but the notion is clearly the same one
he derives from the Ethics.
73
De Malo, q. 2, a. 10, ad 4 (without mentioning Aristotle).

PUNISHMENT AS MEDICINE

19

opposites.”74 Thomas references this passage often and applies it
to many specific questions, for example when explaining why
one ought to correct a sinner privately before denouncing him
publicly,75 why it can be just for public authority to execute,76
and in discussing the doctrine of purgatory.77
For a richer understanding of the medical image, a brief
glance at medieval medicine is in order. Although Thomas does
not seem to have caught much of his teacher Albert’s interest in
the actual science of medicine, he does make liberal use of a
handful of traditional definitions and examples, gathered from
ancient medical science and possibly also from Avicenna’s
Canon of Medicine.78 He accepts the traditional definition of
medicine as the knowledge of health and sickness (scientia sani
et aegri),79 and of health as a balanced mixture of humors
(contemperatio humorum).80 This definition (which will have
implications for the analogy to punishment), presupposes a view
74
Aristotle, Nic. Ethic. 2.3.1104b15, 17-18 (trans. Henry Rackham [New York: G.
P. Putnam’s Sons, 1926]). Aristotle uses a form of the verb κολάζειν, “to chastise,
punish” (Henry George Liddell and Robert Scott, Greek-English Lexicon, rev. Henry
Stuart Jones [Oxford: Clarendon Press, 1940], s.v. “κολάζω”). Later, in discussing
temperance (3.12.1119a22), Aristotle uses a related term, ἀκολασία, to describe the
excess in pleasure-seeking (Rackham translates it “profligacy”).
75
STh II-II, q. 33, a. 7. See also De Virtut., q. 3, a. 2, ad 12 (Quaestiones disputatae
de virtutibus [Turin: Marietti, 1953]): “if a physician proceeds immediately to cut off a
corrupt member, he acts incautiously, and may remove many members which could
have been healed; but if he be wise, he begins with lighter remedies.”
76
STh II-II, q. 64, aa. 2-3.
77
IV Sent., d. 17, q. 3, a. 5, qcla. 2.
78
Avicenna’s Canon of Medicine was known to Thomas, and is cited by name in at
least one place: De Verit., q. 2, a. 8. However, the reference is a very general one from
the beginning of the treatise. Mark Jordan notes that Thomas’s references to medical
authors, both ancient and medieval, are “precisely the sort of aphoristic locus easily
learned at second-hand” (“Medicine and Natural Philosophy in Aquinas” in Thomas von
Aquin: Werk und Wirkung im Licht neuerer Forschungen [New York: Walter de Gruyter,
1988], 236). It seems reasonable to suppose that Albertus Magnus was the proximate
source of Thomas’s knowledge of these authors.
79
VIII Phys., lect. 2 (Commentaria in octo libros Physicorum [Turin: Marietti, 1954],
n. 7).
80
II Phys., lect. 4 (Marietti ed., n. 5); VII Phys., lect. 5 (Marietti ed., n. 6).

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SR. ELINOR GARDNER, O.P.

of the body as containing four bodily humors (blood, black bile,
yellow bile, and phlegm) which produce health when they exist
in balanced proportion, and illness when the balance is disturbed by an excess or deficiency in one of them. The physician,
Thomas notes, “knows health as the form, and cholera and
phlegm as the matter in which health exists, for health consists
in the proper mixture of humors.”81 The medical art, in this
view, attempts to get the body to produce more or less of the
imbalanced humor. To put it another way, medicine acts by way
of instrumental efficient cause in relation to the bodily powers
which are the primary efficient causes. The primary efficient
cause of health is not the medicus, but nature itself, which
medicine assists: “the art [of medicine] does not cause health
principally, but as something helping nature and ministering to
it.”82 Medicine, then, is the art which aids nature in producing
or preserving a proper balance of humors in the body.
Besides this general use of medicina to refer to the healing
art, Thomas also uses the term in the narrower sense of a
specific remedy or treatment, usually painful or unpleasant; this
corresponds to our use of “medicine” to mean either the art as a
whole or a specific substance to be applied or ingested as a
remedy. Both senses of medicina are relevant to the dictum
“punishments are like medicines.” First, poena is like medicine
in the narrow sense, because it is a painful or unpleasant
remedy, something undesirable in itself, and chosen only as
instrumental to something else. Second, drawing on the broad
sense, the infliction of poena is like an act of the medical art
which determines and applies such remedies. We now turn to a
closer examination of these two related features of the medical
analogy: its instrumentality and its artificiality.

81

II Phys., lect. 4 ([Rome: Commissio Leonina, 1884], 2:65): “sicut medicus
cognoscit sanitatem ut formam, et choleram et phlegma et huiusmodi sicut materiam in
qua est sanitas, nam in contemperatione humorum sanitas consistit.”
82
In De Sensu et sensato, tract. 1, proem. (Sentencia libri De sensu et sensato,
[Rome: Commissio Leonina, 1985], 45/2:9, ll. 310-12): “set quia ars non principaliter
causat sanitatem set quasi adiuuans naturam et est ministrans ei.”

PUNISHMENT AS MEDICINE

21

VI. PUNISHMENT AS INSTRUMENTAL GOOD
Punishment, like medicine, is not desired for its own sake. In
his commentary on the text of Aristotle from which the dictum
is taken, Thomas says:
As medicines employ certain bitter drinks and remove agreeable things for the
restoration of health, so also punishments are like medicines for the restoration of virtue, operating through the removal of pleasant things or the application of painful things. For medicines naturally work through contraries, as
when the body’s heat is excessive, physicians apply cold things.83

We have already seen in the definition of poena in De Malo that
punishment is by definition contra voluntatem.84 In both
medicine and punishment, the bitter remedy is desired not for
itself, but for the sake of an end: “a sick person not only wants
to attain health, but even wants to drink bitter medicine, which
he would not otherwise will, that he may attain health.”85 As
medicine is applied to a bodily illness, so punishment is applied
to a spiritual sickness, namely, to sin (peccatum).86 Since the
root of sin is a disordered will, from which disordered acts proceed, its remedy cannot but be “against” this will. Punishment
must be contra voluntatem in the way that medicine must be
contra morbum. The description in both cases does not name
the good to be attained, but the defect to be corrected.
83
II Nic. Ethic. lect. 3 (Marietti ed., n. 270): “Sicut enim medicinae ad sanitatem
restituendam sunt quaedam amarae potiones exhibitae et delectabiles subtractae, ita
etiam poenae sunt quaedam medicinae ad reparandam virtutem. Quae quidem fiunt per
subtractionem aliquarum delectationum vel adhibitionem aliquarum tristitiarum. Quia
medicinae natae sunt fieri per contraria, sicut quando superabundat calor medici
adhibent frigida.” The idea of punishment being the medicine of fault is already present
in II Sent., d. 36, q. 1, a. 3, arg. 3 and ad 3.
84
See also II Sent., d. 36, a. 3 (Mandonnet, ed., 928).
85
De Malo, q. 3, a. 12 (Leonine ed., 23:92, ll. 126-29): “sicut infirmus non solum
uult consequi sanitatem set etiam uult bibere medicinam amaram quam alias nollet, ad
hoc ut sanitatem consequatur.”
86
E.g. “morbus spiritualis hominis viatoris, scilicet peccatum” (De Verit., q. 24,
a. 11, s.c. 4 (Quaestiones disputatae de veritate [Rome: Commissio Lenonia, 1973],
22/3:710, ll. 106-7).

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SR. ELINOR GARDNER, O.P.

One consequence of the instrumental character of punishment is that if a particular punishment is foreseen not to be
conducive to the end, it ought not to be chosen, since
instruments are only desired insofar as they contribute to
bringing about the good at which they aim. A particularly clear
example occurs in a question about the sin of scandal, where
Thomas asks whether it is right to forgo spiritual goods to avoid
the risk of scandal. In one of the replies, he explains:
The infliction of punishments is not sought for its own sake; on the contrary
poenae are inflicted like medicines for restraining sins. And therefore poenae
are just [habent rationem iustitiae] insofar as sins are restrained through them.
But if it were manifest that more and greater sins [peccata] would follow from
the infliction of poenae, then their infliction would not be just [non
continebitur sub iustitia].87

Note that although the punishment in question is deserved,
Thomas maintains that it should not be inflicted, if it can
reasonably be anticipated that it will have no effect in
“restraining sins”: to inflict such a punishment would no longer
belong to justice. This is a clear illustration of the idea that, for
Thomas, reciprocity is not the same as just punishment.
However, the medicinal approach does not in all cases mean
favoring a lesser punishment. In some cases, Thomas argues,
justice may prompt one to multiply or increase deserved
punishments, precisely because “the punishments of the present
life are medicinal, and hence when one punishment is not
enough to coerce a person, another is added, as physicians
prescribe diverse bodily medicines when one is ineffective . . .
but if one punishment suffices, others ought not to be added.”88
Another striking example of this consequence of the
instrumental nature of poena occurs in book 3 of the Summa
contra Gentiles, in a chapter on “how man is freed from sin.”
Thomas argues that in the ordinary course of things man is not
87
STh II-II, q. 43, a. 7, ad 1. This passage is part of a question on whether one ought
to forgo spiritual goods in order to avoid scandal. Thomas argues that although one
ought to avoid being the cause of scandal wherever possible, one cannot omit pursuing
genuine spiritual goods simply for fear that others will take offense.
88
STh II-II, q. 39, a. 4, ad 3.

PUNISHMENT AS MEDICINE

23

freed from sin except through punishment, since it is not
enough for the sin to be forgiven in order for the sinner to be
truly freed from that sin (i.e., if the sinner is still inclined to the
same sin in the future, he is not yet really free). He adds:
We must observe, however, that when the mind is turned away from sin, its
displeasure with sin and the cleaving of its mind to God may be so fervent,
that the obligation to a certain punishment does not remain. For as may be
gathered from what was said above, punishment which someone suffers after
the remission of sin is necessary in order that the mind adhere more firmly to
the good, man being castigated through punishments, which are like
medicines, and that the order of justice be preserved, since he who sinned,
receives a punishment. But the love of God [dilectio ad Deum] suffices to fix
the mind of man firmly in the good, especially if it is fervent, and displeasure
with one’s past fault, when intense, brings great sorrow. Therefore through
fervent love of God and hatred of past sin, the necessity of satisfactory or
purgative punishment is removed, and even if such fervor be not such as
completely to remove punishment, yet the more fervent it is, the less
punishment will be needed [tamen, quanto vehementius fuerit, tanto minus de
poena sufficiet].89

This passage qualifies the assertion two paragraphs earlier that
“the order of justice demands that punishment be awarded for
sin.”90 Evidently, this is not to be taken in the sense of absolute
reciprocity. While ordinarily the order of justice is served when
punishments are meted out for offenses, there will be times
when justice is not served by punishing, either because the punishment would produce greater evils (as in the example of
scandal) or because the penitent’s “detestation of sin” and his
“clinging to God” accomplishes the very “order of justice”
which punishment intends to effect. One does not continue to
use the instrument when the instrument’s end has been
achieved.

89

ScG III, c. 158 (Leonine ed., 14:463a22-b11).
Ibid. (Leonine ed., 14:462b21-22): “Ordo iustitiae hoc requirit ut peccato poena
reddatur.”
90

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SR. ELINOR GARDNER, O.P.

VII. ART AND NATURE IN THE DETERMINATION OF PUNISHMENT
The second feature of punishment highlighted by the medical
analogy is what was called above its “artificiality,” by which is
meant those features of determinations of practical reason
which resemble the features of an art. Unlike the speculative
sciences, which aim at correct knowledge in itself, practical
forms of knowing aim at an activity or a product achieved by
means of correct knowledge.91 The end in such knowing is not
achieved in the art’s exercise itself, but in its product. Thus
medical knowledge is pursued for the sake of medical practice,
and ultimately for the health of those being treated by such
practice. Likewise, political knowledge is pursued for the sake
of political activity (e.g., legislating), and ultimately for the
good of the community of persons subject to such legislation.
While the knowledge required for politics aims at action rather
than at a product, and is thus a species of prudence rather than
of art, the two genera of practical knowing bear some key
similarities.
As a practical form of knowing, medicine aims at an end
already determined and therefore not part of the deliberation of
its practitioners, namely, the good of health.92 Thomas describes
the good sought in punishment in a number of ways: the
restraining of sin,93 the order of justice,94 virtue,95 and peace.96
Ultimately, these descriptions do not indicate different aims, but
different aspects of one and the same aim, for the restraining of
sin is simply the negative condition for virtue, and virtue is the
necessary condition for peace, which Thomas identifies with
91

See VI Nic. Ethic., lect. 3 (Marietti ed., n. 1150).
“In the physician’s action, health is the end; therefore health is not subject to the
choice of the physician, but is rather his starting point [principium]” (STh I-II, q. 13,
a. 3).
93
STh II-II, q. 43, a. 7, ad 1: “poena infliguntur ut medicinae quaedam ad
cohibendum peccata.”
94
ScG III, c. 158 (Leonine ed., 14:463b1-2): “ut etiam ordo iustitiae servetur, dum
qui peccavit, sustinet poenam.”
95
II Nic. Ethic., lect. 3 (Marietti ed., n. 270).
96
See also STh I-II, q. 98, a. 1: “For the end of human law is the peace of the
temporal city” (“Legis enim humanae finis est temporalis tranquilitas civitatis”).
92

PUNISHMENT AS MEDICINE

25

just order. “Peace” is perhaps the most all-encompassing name
for this end, and is especially suggested by the medical analogy,
given the humoral understanding of health described above.
Thus Thomas can say that “as the physician in his action intends
health, which consists in the ordered concord of humors, so the
ruler of the city in his action intends peace, which consists in
the ordered concord of citizens.”97 In both medicine and ruling,
the end is determined prior to any deliberation:
This is what the ruler of a people ought above all to intend, that the unity of
peace be procured. Nor does one rightly consider whether he ought to work
for peace among the people subject to him, any more than the physician about
whether to heal the sick person in his care. For no one ought to take counsel
about the end which he ought to intend, but rather about those things which
are for the sake of the end.98

While the end is given, the means are subject to deliberation,
and it is precisely excellence in such deliberation that makes
someone a possessor of art (or prudence). Unlike the necessary
conclusions of science, these deliberations are contingent,
adapted to the particular nature of the material, the instruments
available, and so on. If there are necessary aspects of art, these
are derived from nature, for example, that clay can only be
shaped before it is baked in the oven.
In his choice of means, the skilled physician applies as much
medicine as is necessary to accomplish the end of healing, not as
much medicine as he can, since medicine is not intended per se,

97

ScG III, c. 146 (Leonine ed., 14:434a38-42): “Sicut medicus in sua operatione
intendit sanitatem, quae consitit in ordinata concordia humorum, ita rector civitatis
intendit in sua operatione pacem, quae consistit in civium ordinata concordia.”
98
De Regno I, c. 2 (De regno ad regem Cypri [Rome: Commissio Leonina, 1979],
ll. 13-19): “Hoc igitur est ad quod maxime rector multitudinis intendere debet, ut pacis
unitatem procuret; nec recte consiliatur an pacem faciat in multitudine sibi subiecta,
sicut nec medicus an sanet infirmum sibi commissum: nullus enim consiliari debet de
fine quem intendere debet, sed de hiis que sunt ad finem.”

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SR. ELINOR GARDNER, O.P.

but on account of an end.99 As Thomas explains in his
commentary on Aristotle’s Politics:
The desire for that which is for the sake of the end is not unlimited, but has a
terminus according to the rule and measure provided by the end, as the
medicinal art tends toward healing without limit, since it produces as much
health as it can, but does not give as much medicine as it can; rather it gives
according to the measure of its utility for healing.100

One might say that the physician applies as much medicine as is
proportionate to the illness, but not the illness considered abstractly, that is, not simply as an instance of this or that species
of illness. The skilled physician does not consult only the nature
of the illness in deciding what and how much to prescribe, but
also the condition and circumstances of the patient. For
example, a cancer treatment that would be proportionate to a
forty-year-old patient may not be proportionate to an eightyyear-old suffering from the same disease. The physician chooses
the medicine proportionate to the illness, considered concretely,
as the condition of this particular patient at this particular time.
Similarly, in political matters, such as the choice of a
particular punishment, deliberations are contingent. Punish99

STh II-II, q. 43, a. 7, ad 1: “The infliction of poenae is not considered on account
of itself, but rather poenae are inflicted like medicines for restraining sins” (“Ad primum
ergo dicendum quod poenarum inflictio non est propter se expetenda, sed poenae
infliguntur ut medicinae quaedam ad cohibendum peccata”). See also STh II-II, q. 184,
a. 3; q. 188, a. 7, ad 1; STh III, q. 15, a. 6, ad 4; V Nic. Ethic., lect. 16 (Marietti ed., n.
1089); and In II Cor., c. 7, lect. 2.
100
I Polit., lect. 8 (Sententia libri Politicorum [Rome: Commissio Leonina, 1971],
48:105, ll. 15-21): “desiderium autem eius quod est ad finem non est in infinitum, sed
habet terminum secundum regulam et mensuram finis: sicut ars medicinalis intendit ad
sanandum in infinitum cum inducit sanitatem quantamcumque potest, set medicinam
non dat quantamcumque potest set secundum mensuram que est utilis ad sanandum.”
Here Thomas is talking about the desire for money. He uses similar medical
comparisons to illustrate the need for discretion in performing exterior acts of piety
such as fasts and vigils, which are desired not for their own sake, but for the sake of
interior acts of faith, hope, and charity, of which we ought to have as much as we can
(In Rom., c. 12, lect. 1) Naturally there is a difference between things like money, which
are good, but merely in an instrumental way, and painful things, which are bad
considered in themselves but may be instrumental to achieving a good. Thus,
punishments are more like medicines than like money.

PUNISHMENT AS MEDICINE

27

ment, in fact, is the example Thomas uses of a determination of
natural law. There is no natural or necessary punishment for a
particular crime, which is why mitigating or increasing punishment according to the circumstances may be just. This does not
make the choice arbitrary or irrational, merely contingent.101 As
the physician prescribing medicine has the health of the patient
in view, so the one determining punishments has the peace of
the community in view. He does not seek to inflict as much
punishment as possible, but as much as is necessary to accomplish the end. Thus the correct model is not one of pure
reciprocity (contrapassum), the view Aristotle attributes to the
Pythagoreans, in which the punishment is to match the severity
and kind of offense as exactly as possible.102 Reciprocity is a
part of the deliberation about punishment, but is of itself an
inadequate measure, as Thomas explains when commenting on
this passage:
[Aristotle] says that in many cases such vengeance [of strict reciprocity] is
found to be discordant with true justice. For example if a ruler were to strike a
private person, justice does not demand that the ruler be struck back, and
similarly, if someone strikes a ruler, he ought not only to be struck, but to be
punished more severely.103

A just punishment considers not only the species of wrong, but
also the condition of the offender and the one offended, and
other circumstances. This by no means does away with
proportionality, as Steven Long rightly points out: to say that a
determination is not necessary is not to say that it is arbitrary.104
Long wants to preserve an aspect of necessity in the
101
Stephen Long, “Evangelium Vitae, St. Thomas Aquinas, and the Death Penalty,”
The Thomist 63 (1999): 527-28.
102
Aristotle, Nic. Ethic. 5.5.1132b21-24 (trans. Irwin).
103
V Ethic., lect. 8 (Marietti ed., n. 968): “dicit quod in multis locis talis vindicta
invenitur dissonare verae iustitiae, ut si aliquis in principatu constitutus percusserit
aliquam privatam personam, non requirit hoc iustitia quod princeps repercutiatur, et
similiter, si aliquis percutiat principem, oportet quod non solum percutiatur, sed quod
etiam gravius puniatur.”
104
Long, “Evangelium Vitae, St. Thomas Aquinas, and the Death Penalty,” 528.

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SR. ELINOR GARDNER, O.P.

determination of punishment, suggesting that some determinations might be “necessitated” insofar as “given a certain
second matter, there is only one way to achieve some given
effect.”105 Yet since the lack of necessity is precisely what causes
the need for determination, this is puzzling. In the determinations of art, whatever necessity exists arises from the
natural materials being used in the art; likewise, in the
determination of punishment, whatever necessity exists arises
from the nature of the human acts in question (both the
wrongful acts to be punished, and the range of acts by which
such wrongs can be punished). Long conceives of determination
as a kind of particularization of a (universal) form, a
comparison suggested by Thomas in the question on human
law. However, in Thomas’s use of this comparison, the form is
not just being made concrete (particularized); rather, that which
is general (e.g., the form of house) is being specified (to a
particular kind of house).106 Again, the need for such specification arises precisely because the generality belonging to
natural law cannot be particularized without first being
specified, and this specification is the work of prudence.107
In summary, reciprocity plays the role in punishment that
pathology plays in medical treatment. That is, it provides the
one making the determination certain boundaries within which
he must make his judgment. The physician must know the
nature and extent of the disease he is treating, and the types of
treatments that can be used for this disease; likewise, the one
punishing must know the nature of the crime he is punishing
and the range of penalties available to him. Such knowledge

105

Ibid., 529.
STh I-II, q. 95, a. 2: “The second way [in which precepts are derived from natural
law] is like that in the arts when general forms [formae communes] are determined to
something specific [ad aliquid speciale], as when an architect has to determine the
general form of house to this or that shape of house.”
107
General precepts could also be specified by divine decree, as in the Mosaic Law.
However, Thomas argues that the New Law, the Law of the Gospel, does not impose
specific judicial precepts, leaving these to the determination of men (STh I-II, q. 108,
a. 2, ad 4).
106

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29

provides the basis for deliberation about treatment or about
punishment, but it is not itself the determination.
VIII. MINISTRA NATURAE
The term that for Thomas captures the nature of the
relationship between the practitioners both of art and of
political prudence is minister. A minister is what Thomas calls
causa adiuvans, a helping or assisting cause, for the minister is
not the principal agent in those actions pertaining to his
ministry, but an assisting cause, one who “works not for his
own end, but for another’s.”108 This is true of the physician:
medicine assists nature in achieving nature’s end, health. In
medical acts, Thomas notes, the principal agent (agens
principale) is not the physician: “Medicine is like an instrument
to nature, which is the principal agent in causing health.”109
“The physician heals as exterior assistant, and nature as an
interior agent.”110 Medical actions assist the body in achieving
health by removing obstacles, promoting some natural processes
and inhibiting others, and, in general, by helping those internal
causes which are primarily responsible for health. Thus the
medical art is called by Thomas ministra naturae since “it is
nature that heals, to which medicine is a minister.”111 And the
physician himself is a minister to nature (minister naturae) “by

108
II Phys., lect. 5 (Leonine ed., 2:70): “the efficient cause is fourfold, namely,
perfecting, preparing, helping, and counseling” (“quadruplex est causa efficiens, scilicet
perficiens, praeparans, adiuvans et consilians. . . . Adiuvans vero est, quod non operatur
ad proprium finem, sed ad finem alterius”).
109
De Pot., q. 6, a. 5, ad 2 (Quaestiones disputatae de potentia ([Paris, 1883],
1:309): “quia medicinae corpori humano exhibitae operantur ad sanitatem quasi
instrumenta; natura autem est sicut agens principale.”
110
Q. D. De Anima, q. 4, ad 6 (Quaestiones disputatae de anima [Rome: Commissio
Leonina, 1996], 24/1:36, ll. 246-47): “medicus sanat sicut exterius aminiculans, natura
autem tamquam interius agens”
111
De Verit., q. 11, a. 1 (quoted below). See also De Spir. Creat., a. 9, ad 7 (Quaestio
disputata de spiritualibus creaturis [Rome: Commissio Leonina, 2000], 24/2:98,
ll. 475-79).

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SR. ELINOR GARDNER, O.P.

strengthening nature and applying medicines, which nature uses
like instruments for healing.”112
We can see evidence of a similar thought in the use of terms
like “prime minister,” though the reason may be obscured by
the same contractarian way of thinking about political life that
affected Finnis’s account of punishment. For under that view, it
is not obvious what prior and “natural” reality is being served
by the political agent, unless it is simply the will of the majority.
For Aristotle and Thomas, on the other hand, the political body
is a natural entity, insofar as it is the term of a natural
process,113 a process that is rooted in, and provides the end for,
that activity which belongs to man by virtue of his rational
nature: speech. The capacity for language is actualized in
deliberation about what is just and unjust. “But communication
about such things makes the household and the city. Therefore
man is naturally a domestic and civic animal.”114
Yet civic society is not produced by nature as a complete
thing; it requires human establishment, involving deliberation
and choice, and thus can reasonably be called a work of art. In
considering this portion of Aristotle’s Politics, Thomas
comments:
[Aristotle] treats of the institution of the civic community, concluding from
the foregoing that among all men there is a certain natural impulse toward the
civic community, as there also is toward the virtues. Even so, as the virtues are
acquired through human efforts, as he says in the second book of the Ethics,
so also are civic communities instituted by human activity. And the one who

112

De Verit., q. 11, a. 1 (Leonine ed., 22/2:351, ll. 295-99): “Sicut medicus in
sanatione est minister naturae quae principaliter operatur, confortando naturam et
apponendo medicinas quibus velut instrumentis natura utitur ad sanationem.” Here
Thomas is comparing the physician to the teacher, who acts as the instrumental cause of
the coming to be of knowledge in the student.
113
“There is in everyone by nature an impulse toward this [political] sort of
community” (Aristotle, Politics 1.2.1253a30 [trans. Carnes Lord, 2nd ed. (Chicago:
University of Chicago Press, 2013)]).
114
I Polit., lect. 1 (Leonine ed., 48:79a152-54): “Set communicatio in istis facit
domum et ciuitatem; ergo homo est naturaliter animal domesticum et ciuile.”

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31

first instituted the civic community was the cause of the greatest goods for
man.115

Even though the civic community is natural, it still requires
“makers”; it is thus a work both of nature and of art. The
political “art,” like the medical, ministers as an assisting cause to
a more primary, natural activity, found in the human inclination
to communicate about what is just and unjust. From this point
of view, in contrast to the contractarian view, the work of
political “experts” is to help direct the inclination toward social
life more effectively toward its given end. One of the ways in
which this is done is by prescribing particular punishments for
particular crimes. Thomas calls this determinatio, and
punishment, as we have seen, is his prime example for such
judgments.116
IX. “DEI MINISTER EST”
As noted at the beginning of this essay, contemporary
literature on punishment revolves around the task of
“justifying” punishment, that is, of defending it against the
charge that acts of punishing are acts of injustice.117 Attempting
to give a Thomistic “justification” of punishment is somewhat
like attempting to give a Thomistic theodicy (it tries to make
Thomas answer a question which his own account would render
115
Ibid. (Leonine ed., 48:79a200-208): “Deinde . . . agit de institutione ciuitatis,
concludens ex premissis quod in omnibus hominibus inest quidam naturalis impetus ad
communitatem ciuitatis, sicut et ad uirtutes; set tamen sicut uirtutes acquiruntur per
exercitium humanum, ut dicitur in II Ethicorum, ita ciuitates sunt institute humana
industria. Ille autem qui primo instituit ciuitatem fuit causa hominibus maximorum
bonorum.”
116
“Punishment is the tradition’s stock example of the need for determinatio, a
process of choosing freely from a range of reasonable options none of which is simply
rationally superior to the others” (Finnis, “Retribution,” 103).
117
Though Finnis presents his reading of Thomas in dialogue with contemporary
accounts of punishment (Hart, Morris, etc.), his starting point is different. He challenges
Nietzsche’s genealogy of punishment, providing an alternative account of what
punishment in fact is.

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SR. ELINOR GARDNER, O.P.

incoherent).118 For since Thomas takes the notion that “punishment is due to sin” as a first principle in moral reasoning, he
cannot also prove that punishment is just; this would amount to
demonstrating the indemonstrable. What needs to be proven is
not that punishment in general is just, but that this or that
punishment is just, or that this or that person ought to punish.
In other words, it is not a matter of justification but of
determination.
If there is a sense in which Thomas is interested in “justifying” punishment, then, it is in justifying the authority of
human agents to punish. Of course, if human punishments were
the only punishments there were, this would be a distinction
without a difference. And this brings us to the crucial point. The
ultimate reason Thomas is not a “retributivist” in the modern
sense is not that he rejects the importance, the necessity, and the
goodness of retribution, but that he does not think of
retribution as something primarily found in human institutions
or accomplished by human agents. In his view, retribution
belongs primarily and properly to God, a view founded in
revelation and supported by the Fathers.119
In Thomas, the derivative nature of human punishment can
be seen in the treatment of the virtue of vindicatio or just
vengeance. The first article of question 108 in the Secunda
118
Edward Feser argues that the logical problem of evil (and the evidential problem)
is based on a category error. See his “The Thomistic Dissolution of the Logical Problem
of Evil” Religions 12:268 (2021) (https://www.mdpi.com/2077-1444/12/4/268).
119
See Anselm, Cur Deus homo I, c. 12: Presented with the objection that since the
Lord commands us in the Gospel to forgive all wrongs against us, that God himself
cannot be less merciful than he commands us to be, Anselm says that “God is giving us
this teaching in order that we should not presume to do something which belongs to
God alone. For it belongs to no one to take vengeance except to him who is Lord of all.
I should explain that when earthly powers take action in this way in accordance with
right, it is the Lord himself, by whom they have been appointed for the task, who is
acting.” (Anselm of Canterbury, The Major Works, ed. Brian Davies and G. R. Evans
[Oxford: Oxford University Press, 2008], 285) See also Augustine, Letter 100, n. 1:
“We [Christians] are not looking for vengeance on earth over our enemies . . . we do
want public authority to act against them, but not to make use of the extreme
punishment [of death] which they deserve” (Letters of Saint Augustine, Vol. II (83-130),
vol. 18 of The Fathers of the Church: A New Translation [Washington, D.C.: The
Catholic University of America Press, 1953], 142).

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33

secundae asks whether vindicatio is “permitted” or “licit”
(licita). After rejecting the desire for vengeance based on hatred
and intending the harm of another as the end, Thomas concludes that there is a licit intentio vindicandis, which is not per
se mala:
If the intention of the one seeking vengeance is moved mainly toward
something good to be achieved through punishment of the sinner, for instance
the amendment of the sinner, or at least toward his being restrained and the
peace of others, and toward the conservation of justice and the honor of God,
such vindication can be licit, other due circumstances being observed.120

Apart from the argument itself, we must note the significance of
asking whether vindicatio is licit, since this is not a question
asked about every virtue.121
In one sense, as Thomas says elsewhere, “everything contrary
to a precept of the natural law is illicit,”122 but that is not the
sense intended here. Thomas is inquiring whether something
violates divine law, and more specifically, the New Law. This is
a question that only arises in the presence of an explicit divine
injunction, whether in the form of a command or a counsel.123
120

STh II-II, q. 108: “Si vero intentio vindicantis feratur principaliter ad aliquod
bonum, ad quod pervenitur per poenam peccantis, puta ad emendationem peccantis, vel
saltem ad cohibeitionem eius et quietem aliorum, et ad iustitiae conservationem et Dei
honorem, potest esse vindicatio licita, aliis debitis circumstantiis servatis.”
121
Most often the first article of a question in the Secunda secundae begins with
asking whether the quality in question is a virtue, or whether it is a specific virtue. In a
handful of questions this consideration is preceded by a question about licitness:
whether it is licit to judge others (q. 60); whether it is licit to resist evildoers by war,
killing, and other forms of violence (qq. 40, 64, 65); whether it is licit to take oaths
(qq. 89-90), to possess property (q. 66), and to maintain perpetual continence (q. 152).
Two other questions include similar queries about acts or passions which are the matter
for a virtue: q. 149, a. 3 asks whether the use of wine is licit, which pertains to the
virtue of sobriety; and q. 158, a. 1 asks whether the passion of anger can be licit, which
relates to the virtue of vindicatio.
122
STh II-II, q. 152, a. 2, obj. 1: “Omne enim quod contrariatur praecepto legis
naturae est illicitum.”
123
In some of the cases mentioned above, the Lord’s words seem to forbid
something: judging others, killing, taking oaths, possessing property, drinking wine,
being angry. In q. 152, he recommends something (perpetual continence) that would

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SR. ELINOR GARDNER, O.P.

We find that the questions about lawfulness all pertain to those
evangelical teachings in which Jesus is said to fulfill the moral
precepts of the old law.124 For example, the question on oathtaking, after asking whether taking an oath (iurare) consists in
invoking God as a witness (STh II-II, q. 89, a. 1), immediately
proceeds to a consideration of the lawfulness of this practice.
The reason is that a literal reading of Matthew 5:34 (and James
5:12) would conclude that oaths are altogether forbidden.125
Thomas argues that oath-taking is not wrong, even though it
can be used wrongly, and it is not altogether forbidden by the
Lord’s saying in the Gospel, although the evangelical teaching
encourages a severe restriction to prevent irreverence and other
faults. The Letter of James confirms this teaching.126
The discussion of the lawfulness of vindicatio in article 1 of
question 108 follows a similar pattern. As in the article on the
lawfulness of oath-taking, all of the objections are scriptural.
Already in the Old Testament, we find a check on the appetite
for vengeance in Deuteronomy 32:35. It would seem, as the
first objection concludes, that to take vengeance is to usurp
something that belongs properly to God, making it a vice
against justice (failing to give what is owed, not to men, but to
God).127 This is made even clearer in the New Testament, as the
third objection argues: “Vengeance is taken through punishments, from which servile fear is produced. But the new law is

seem to contradict a previous divine injunction (“Be fruitful and multiply” Gen. 1:28).
But in each case, the question arises precisely because of explicit divine legislation.
124
In Matt., c. 5, lect. 7 (Marietti ed., n. 476) (Lander, Wyo.: Aquinas Institute for
the Study of Sacred Doctrine, 2013): “in prima adimplet legem quantum ad praecepta
moralia.”
125
STh II-II, q. 89, a. 2, obj. 1: “For nothing which is prohibited in the divine law is
licit. But oath-taking is prohibited in Matt 5:34, ‘But I say to you, do not swear at all’”
(“Nihil enim quod prohibetur in lege divina est licitum. Sed iuramentum prohibetur
Matth. 5, [34]: Ego dico vobis, non iurare omnino”).
126
See STh II-II, q. 89, a. 2, ad 1.
127
“Quicumque enim usurpat sibi quod Dei est, peccat. Sed vindicta pertinet ad
Deum: dicitur enim Deut. 32, [35], secundum aliam litteram: Mihi vindictam: et ego
retribuam. Ergo vindicta est illicita.”

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not a law of fear, but of love. . . . Therefore, at least in the New
Testament, vengeance ought not to be taken.”128
Note that even though Thomas indicates (in the sed contra)
that vindicatio is not per se malum, and argues (in the corpus)
that the intention in vindicatio may be virtuous and not sinful,
he is not engaged in the kind of abstract justification that we
find in the contemporary retributivists. That God himself takes
vengeance is presumed (since it is evident from Scripture, both
Old and New Testaments), and “nothing is to be expected from
God except what is good,” as the sed contra notes. The doubt is
about whether it is right for human beings to take vengeance.
Thomas argues that vindicatio may be permitted to men, so
long as one intends the right thing, namely, not the pain to be
inflicted on the sinner, but the good to be accomplished
thereby. The one who does this “does not usurp what is proper
to God,” as the first objection suggests, “but uses the power
divinely conceded to him.”129 Thomas grants the objector’s
major premise: vengeance does truly and properly belong to
God. The reason men can take vengeance is indicated by St.
Paul in Romans 13:4 (RSV): “But if you do wrong, be afraid,
for he is the servant [διάκονός - Vulg. minister] of God to
execute his wrath on the wrongdoer.” In Romans 13:1-7, Paul
teaches that all human authority is derived from God. To mete
out deserved punishment is to exercise a power which belongs
properly to God;130 hence it is either a usurpation or an exercise
of instrumental (ministerial) power.
128
“Praeterea, vindicta per poenas fit, ex quibus causatur timor servilis. Sed lex nova
non est lex timoris, sed amoris, ut Augustinus dicit, contra Adamantum. Ergo, ad minus
in novo testamento, vindicta fieri non debet.”
129
STh II-II, q. 108, a. 1, ad 1: “non usurpat sibi quod Dei est, sed utitur potestate
sibi divinitus concessa.”
130
In Rom., c. 13, lect. 1. See also STh II-II, q. 108, a. 1, ad 1. Thomas interprets the
derivation of power from God in a metaphysical, not an historical sense. It is not
necessary that the ruler be able to trace his authority back to an explicit divine
appointment, as Sir Robert Filmer tried to do (John Locke’s target in the First Treatise
of Government). It must, however, be obtained lawfully, and “[observe] the precepts of
divine justice” (In Rom., c. 13, lect. 1).

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Not only is the authority to punish derived from God, it is
also subject to divinely given limitations. The limitation in this
case does not derive from a Benthamite calculus (because
punishments are unpleasant, and pleasure is the ultimate good,
one ought to reduce punishments to the absolute minimum
necessary in order to prevent greater unpleasantness); nor does
it arise from a Lockean premise of an individual right to punish
malefactors which men relinquish to the civil authority in order
to secure a happier life for themselves.131 Unlike Locke, Thomas
sees punishment as an exercise of political authority existing in
the community as a whole, rather than a natural right existing
in the individual.132 For Thomas, the limitation on human
punishment derives from reverence for the divine lawgiver, to
whom punishment properly belongs, and depends on divine
(revealed) law.133
131

“And that all Men may be restrained from invading others Rights, and from doing
hurt to one another, and the Law of Nature be observed, which willith the Peace and
Preservation of all Mankind, the Execution of the Law of Nature is in that State, put into
every Mans hands, whereby every one has a right to punish the transgressors of that
Law to such a Degree, as may hinder its Violation” (John Locke, Two Treatises of
Government, ed. Peter Laslett [Cambridge: Cambridge University Press, 2008], II, §7,
ll. 1-7) For Locke the right to punish is a natural, individual right.
132
STh I-II, q. 97, a. 3, ad 3: “Therefore although it is not possible for individual
persons to make law, the people as a whole can do so.” In the case of punishment,
which involves harming someone who is a part of the community, only the community
has the authority to decide to sacrifice a part for the good of the whole (STh II-II, q. 64,
a. 3, ad 3). Insofar as it is exercised by an individual ruler (see STh I-II, q. 105 on the
superiority of monarchy), this individual acts on behalf of the entire people. And the
precepts that he makes (praecepta iudicialia, as contrasted with praecepta moralia) are
changeable, not being essential to justice in itself (STh I-II, q. 105, a. 2, ad 4).
133
The idea that the human power to punish derives from God has scriptural roots
beginning in the Book of Genesis with the divine injunction regarding Cain in Genesis
4:15. Cain’s fear that “whoever finds me will kill me” can be cited as evidence of the
natural tendency toward vengeance; the Lord’s words show that this tendency is not
simply to be acted upon. In fact, God explicitly forbids this by putting his mark on Cain,
and it is not until after the Flood that the descendants of Noah are instructed:
“Whoever sheds the blood of man, by man shall his blood be shed” (Gen 9:6 [RSV]).
According to some Scripture scholars, this “ancient legal formula . . . was probably
originally intended to set limits to blood revenge” (Collegeville Bible Commentary, ed.
Dianne Bergant and Robert J. Karris [Collegeville, Minn.: The Liturgical Press, 1989],
49). “Modern scholars have pointed out that the text actually has a chiastic structure,

PUNISHMENT AS MEDICINE

37

Regarding the limitations of human punishment, Thomas
thinks that while human punishment aims to be proportional
(this is included within the very ratio of punishment), it
recognizes that “the punishments inflicted in the present life,
whether by God or by man, do not always correspond to the
gravity of the fault.”134 Only God can punish a wrongdoer
exactly as he deserves; divine (eternal) retribution alone is
properly and fully retributive, while at the same time being
perfectly medicinal.135 Not only are human beings lacking in
knowledge of true desert, they also tend toward excess in
punishing, an extreme that must be counteracted by restraint.136
typical of Hebrew wisdom literature. Recent translations, including the NAB, indicate
that the verse is thus poetic in form, yet biblical laws were never written in poetic form”
(James Megivern, The Death Penalty: An Historical and Theological Survey [Mahwah,
N.J.: Paulist Press, 1997], 15). Further, while the laws given through Moses were
accompanied by the establishment of governing authority, this was not the case with the
revelation to Noah, which was not accompanied by any special authority to legislate and
to punish. Rather than commanding a specific punishment, the Noahic covenant
sanctioned and set limits to the already established practice of blood-vengeance.
134
De Malo, q. 2 a. 10 ad 4 (Leonine ed., 23:58, ll. 114-16): “Set pene que in
presenti uita infliguntur siue a Deo siue ab homine non semper respondent grauitati
culpe.” In this reply, Thomas includes divine temporal punishments along with human
punishments as falling short of the true measure, not of course because of any lack of
knowledge or power in God, but precisely because “the punishments of the present life
are applied as medicines.” Surprisingly, Thomas gives this as the reason why a lesser
fault may be punished more severely than a graver one, in order to avoid a great
temporal danger. It should be noted that the objection to which he is replying compares
two punishments prescribed in the Torah, which both correspond to serious sins, schism
and blasphemy, but one of which, being an offense against God, is considered more
grave, and yet is punished less severely. Both are punished with death, in fact, but while
blasphemy was punished by stoning, the schism in Numbers 26: 10 was punished by the
death of many.
135
“Divine retribution or punishment for sin, far from being an act of hatred toward
the sinner, is above all an act of mercy, for it is directed to healing the sinner’s will (STh
I, q. 45, a. 6, corp. and ad 2). . . . Like a good physician providing the necessarily
painful remedy for a deadly disease (e.g., chemotherapy for cancer), Aquinas’s God acts
to cure disordered ‘values’ through an involuntary but health-restoring therapy (STh I,
q. 48, a. 5)” (James Lehrberger, O. Cist., “Nietzsche and Aquinas,” The Thomist 80
[2016]: 451).
136
The question on the virtue of vengeance should be read together with the
question on the virtue of clemency in STh II-II, q. 157.

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SR. ELINOR GARDNER, O.P.

Finally, even if human authorities were possessed of the best
knowledge and dispositions, they would still lack the power to
accomplish perfect retribution. Thus human punishment is
guided by the more modest aim of serving the community’s
good (and that of the offender, who is part of that community)
in inflicting punishments that respond to wrongs in a proportional way. From this we see why Thomas consistently refers
to punishment as medicine, and that where he distinguishes
between human and divine (or temporal and eternal)
punishment, “medicinal” becomes the specific difference
identifying human, temporal punishment.
Thomas holds human punishment to be retributive, but it is
misleading to call him a “retributivist” insofar as the term
implies that retribution is something that can be achieved by
human agents. While “punishment is due to sin,”137 it is due
primarily from God. It is due also from the human community
insofar as this community was offended by the crime. That is,
the human obligation to punish is defined by the temporal good
of the particular community in question, for which those human
authorities are responsible before God, and not by a general
obligation to set right the cosmic imbalance produced by
wrongdoing. Thus “human law does not prohibit all vices . . .
but only the more grave, from which it is possible for the
majority to abstain, and principally those which are harmful to
others, without the prohibition of which human society could
not be preserved.”138
Such human punishments are ministerial: those who inflict
them are like the stewards in the Gospel parable, making
judgments for now, according to the guidance left them,
awaiting the return of the master and the true manifestation of
righteousness. Civil punishments accomplish their ministerial
function to some degree, but it is in the Church’s sacramental
life that one finds more perfect remedies; as Thomas says in a
comment on Matthew 21, “spiritual illnesses cannot be cured
137

STh II-II, q. 108, a. 4, s.c.
STh I-II, q. 96, a. 2. The attempt by civil law to do more than inhibit the grosser
vices would tend to produce more evil than good, as Thomas suggests (ibid., ad 2).
138

PUNISHMENT AS MEDICINE

39

except in the Church.”139 It is worth noting, although we cannot
explore it here, that the medical image features prominently in
Thomas’s treatment of the sacrament of penance.140
X. IMPLICATIONS FOR THE PHILOSOPHY OF PUNISHMENT
The placement of human punishment in its metaphysical and
theological context has far-reaching implications for philosophical treatments of punishment. When philosophers came to
the defense of retributive punishment in the second half of the
twentieth century, it was a purely secular retributivism, without
reference to divine retribution. According to Michael Davis, in
fact, one of the reasons for the major development of
punishment theory in the latter half of the twentieth century
was precisely the decision to exclude “various other topics
which, though using the term ‘punishment’ (in a recognizably
related sense), seem to belong to other fields . . . [e.g.] divine
punishment of the traditional Christian sort.”141 John Finnis
similarly argues that “hell is only by an extended analogy a
matter of punishment.”142 Finnis and the philosophers to whom
Davis refers imply more than simply the assertion that
139
In Matt., c. 21, lect. 1 (Marietti ed., n. 1700): “morbi spirituales non curantur nisi
in Ecclesia.”
140
See, e.g., STh III, q. 84, a. 10, ad 5: “penance derives its power from Christ’s
Passion, as a spiritual medicine.” ScG IV, c. 72, which asserts the necessity of the
sacrament of penance for the remission of postbaptismal sin, notes that while the body
can sometimes heal itself without the help of medical art, the restoration of spiritual
health requires external aid: “for man to be cleansed of sin, it is necessary not only that
the mind adhere to God, but also to the mediator between God and man, Jesus Christ,
in whom the remission of all sins is given: for spiritual health consists in the turning of
the mind to God, which we cannot attain except through Jesus Christ, the physician of
our souls” (Leonine ed., 15:225b23-31) The current Code of Canon Law likewise
describes the forgiveness of sins in the sacrament of confession in medicinal terms.
Canon 978 §1 reads: “In hearing confessions the priest is to remember that he is equally
a judge and a physician and has been established by God as a minister of divine justice
and mercy, so that he has regard for the divine honor and the salvation of souls.”
141
Davis, “Punishment Theory’s Golden Half Century,” 75.
142
Finnis, “Retribution,” 103.

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SR. ELINOR GARDNER, O.P.

punishment is said analogously (a claim with which Thomas
would agree). Divine punishment, they imply, and more
precisely, the eternal punishment of hell, is not really relevant
to understanding the human phenomenon of punishment.143
Certain methodological assumptions about the autonomy of
philosophical inquiry may make it impossible for the contemporary analytic philosopher to consider divine punishment,
but this was not a problem for Thomas, for whom, as we have
seen, just human punishment is inconceivable apart from its
divine source. If he is correct, attempts to justify human
punishment on a merely human basis are doomed to fail.
So argued Dietrich von Hildebrand in 1932 in a short essay
on the nature of punishment. Hildebrand warns of the grave
mistake being made by those who begin their thinking about
punishment with civil punishment, and fail to place this reality
in its proper metaphysical context.144 In the end, Hildebrand
argues, only God can punish. Human agents can do so only
insofar as they act in God’s place.145 In systems that reject God,
this means that “punishment” becomes something else: therapy,
mediation, a political tool.146 For the Christian, on the other
hand, punishment remains a necessary responsibility of public
143

This seems to suggest that they think of punishment as an instance of
metaphorical as opposed to proper analogy. For a detailed discussion on the
relationship between metaphor and analogy, see Ralph McInerny, Aquinas on Analogy
(Washington, D.C.: The Catholic University of America Press, 1996), 134-36.
144
One must begin with a metaphysical consideration of the essence of punishment,
which shows us the intrinsic connection between moral guilt and punishment, such that
“there can be no true consciousness of guilt without thinking [oneself] deserving of
punishment” (Dietrich von Hildebrand, “Zum Wesen der Strafe,” in Gesammelte
Werke, Band VIII: Situationsethik und kleinere Schriften [Regensburg: J. Habbel, 1974],
260) Punishment is what Hildebrand calls a “value response,” which alone constitutes
an appropriate response to moral evil, altering the cosmic effect of that evil (ibid., 264,
270).
145
Ibid., 273-74. This is the traditional patristic view captured in Anselm’s comment,
quoted above.
146
Or “restorative justice,” which the OED describes as “an approach to criminal
justice focusing on rehabilitation of offenders through reconciliation with victims and
the community at large” (Oxford English Dictionary, s.v. “restorative”). However,
insofar as this approach requires the offender’s acknowledgement of guilt and desire to
seek reparation, it has something in common with the notion of satisfaction.

PUNISHMENT AS MEDICINE

41

authority, entrusted to it by God; its retributive form cannot be
replaced with something else, for retribution links human
punishment to God as the source of its legitimacy, as Pius XII
notes: “In the metaphysical order the punishment is a
consequence of our dependence on the supreme Will, a
dependence which is written indelibly on our created nature.”147
Separated from this foundation, civil punishment necessarily
appears in need of justification, a justification that turns out to
be difficult to supply. From a purely secular perspective, punishment remains a paradox.148 On the one hand, we experience in
ourselves the inclination toward retribution as something good.
On the other hand, we see nothing in the nature of things that
would give one man such power over another, equal to him in
dignity.149 Moreover, we see the excesses toward which the
natural appetite of vengeance leads, and the unending cycle of
violence in which it lands us, classically illustrated in the history
of the house of Atreus.
Divine law teaches us both to think of punishment as something good and to restrain our appetite for it. The divine source
of punishment, as we have seen, is not only a justification of
human punishment, but also a motive for its restraint, derived
not from a rejection of retribution, but from reverence for the
divine judge, and knowledge of human weakness. The Gospel
teaches us not to avenge ourselves, and also to hunger and thirst
for justice. Our desire to right wrongs is fulfilled only when it is
offered back to God, from whom it came. Not surprisingly,
147
Pius XII, “Address to the Sixth Congress of International Penal Law (3 Oct
1953),” in Yzermans, ed., Major Addresses of Pius XII, 256.
148
Sher describes “the air of paradox that surrounds the assertion that actions that
are wrong in ordinary contexts are permissible or mandatory as punishment” (Desert,
69).
149
Even reference to the common good runs into difficulty, insofar as one wants to
affirm that even the criminal retains his dignity and does not become merely
instrumental with respect to the good of the whole. See the Catechism of the Catholic
Church (Vatican City: Libreria Editrice Vaticana, 2003 [rev. 2018]), n. 2267: “Today,
however, there is an increasing awareness that the dignity of the person is not lost even
after the commission of very serious crimes.”

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SR. ELINOR GARDNER, O.P.

Thomas finds a model of this twofold attitude in the Apostle
Paul, ready to use severity when necessary for the good of the
Christian community (and the good of the offender), yet ever
ready to welcome back the repentant sinner with the same
mercy that had been shown to him, the worst among sinners
(1 Tim 1:15). On the words of Paul to the Corinthians, “I
rejoice, not because you were grieved, but because you were
grieved unto repenting” (2 Cor 7:9 [RSV]), Thomas offers the
following comment, with which we can appropriately close our
reflections:
[Paul] gives the reason for his joy, because I am not glad that you were made
sorrowful, but at the effect, namely, your amendment, because you were made
sorrowful, not unto despair, but unto penance; just as a physician is not glad
at the bitterness of the medicine, but at the effect, namely health: as sorrowful,
yet always rejoicing (2 Cor 6:10).150

150

In II Cor., c. 7, lect. 2 (trans. Fabian R. Larcher, O.P. [Lander, Wyo.: Aquinas
Institute for the Study of Sacred Doctrine, 2020; originally published 1991]).
I am very much indebted to Sr. Mary Madeline Todd, O.P., Fr. James Lehrberger,
O.Cist., Sr. Marian Sartain, O.P., the participants in the 2021 meeting of the Texas
Consortium for Christian Ethics, as well as the editor of The Thomist and two
anonymous reviewers, for comments on earlier versions of this paper, which have
improved its form and content considerably.

The Thomist 87 (2023): 43-86

NATURE DOES NOTHING IN VAIN:
REEXAMINING AQUINAS’S FIFTH WAY
JOEL JOHNSON
Borromeo Seminary Institute at John Carroll University
Cleveland, Ohio

A

T THE BEGINNING of his Summa theologiae, Thomas
Aquinas famously presents his Five Ways to demonstrate
the existence of God. In each of the Five Ways, he draws
attention to some general feature of the world and argues that
this feature can only be explained by a divine being. In his Fifth
Way, Aquinas takes as his starting point the observation that
beings that lack cognition act for the sake of ends, and his
explanation for this phenomenon is a divine intelligence who
directs such beings to their ends. However, as is the case with
each of the Five Ways, the proper interpretation of the Fifth
Way is a matter of dispute. Commentators disagree about both
the precise nature of the end-directed activity in question and
the exact manner in which an intelligent being explains it. In
this article, I consider the three dominant interpretations of the
Fifth Way found in recent literature and argue that, while each
of these interpretations accurately captures important elements
of Aquinas’s understanding of final causality, each interpretation also faces serious textual or philosophical difficulties. I
then propose a fourth interpretation of the Fifth Way that
circumvents the problems that undermine these other
interpretations.
The fact that the text of the Fifth Way is interpreted in
several incompatible ways is in large part due to its brevity.
Aquinas states the entirety of the argument as follows:

43

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JOEL JOHNSON

The fifth way is taken from the governance of things: We see that some things
lacking cognition, namely, natural bodies, act for an end. This is apparent
from the fact that they always or very frequently act in the same way so that
they attain what is best, and from this it is clear that it is not by chance, but
intentionally, that they attain the end. But things lacking cognition tend
toward an end only if they are directed by something that has cognition and
intelligence, in the same way that an arrow is directed by an archer.
Therefore, there is something with intelligence by which all natural things are
ordered toward an end—and this we call a God.1

At its core, the argument is a simple modus ponens:
1. Things that lack cognition, namely, natural bodies, act for an end.
2. If natural bodies act for an end, then they must be directed to the end by
something with cognition and intelligence.
3. Therefore, there exists something with cognition and intelligence that
directs natural bodies to an end, and this we call a God.

Although this basic characterization of the argument is accepted
by each of the rival interpretations considered in this paper,
disagreements arise in their attempts to clarify both the meaning
of and the justification for both premises.
However, before turning to these rival interpretations, three
preliminary points must be addressed.2 First, while Aquinas is
clear elsewhere in his corpus that the activity of every being is
1
STh I, q. 2, a. 3: “Quinta via sumitur ex gubernatione rerum. Videmus enim quod
aliqua quae cognitione carent, scilicet corpora naturalia, operantur propter finem, quod
apparet ex hoc quod semper aut frequentius eodem modo operantur, ut consequantur id
quod est optimum; unde patet quod non a casu, sed ex intentione perveniunt ad finem.
Ea autem quae non habent cognitionem, non tendunt in finem nisi directa ab aliquo
cognoscente et intelligente, sicut sagitta a sagittante. Ergo est aliquid intelligens, a quo
omnes res naturales ordinantur ad finem, et hoc dicimus Deum.” I translate the key
phrase ex intentione as “intentionally” rather than the more typical renderings
“designedly” or “by intention” with the hope that this translation avoids favoring one
interpretation over the others. Unless otherwise noted, all translations are my own and
are based on the Latin text from Sancti Thomae de Aquino, Opera omnia, Iussu
impensaque, Leonis XIII P.M. edita (Rome: Ex typographia polyglotta S. C. de
Propaganda Fide, 1882-).
2
In addition to the three points discussed here, I leave aside a number of other
textual issues. Marie George discusses some of these issues in her “A Thomistic Rebuttal
of Some Common Objections to Paley’s Argument from Design,” New Blackfriars 97,
no. 1069 (2016): 266-88.

AQUINAS’S FIFTH WAY

45

for the sake of an end,3 in the Fifth Way he narrows his focus to
a specific class of beings: “things lacking cognition, namely,
natural bodies.” The kinds of beings he has in mind when he
refers to “natural bodies” (corpora naturalia) are physical,
nonliving beings like wood, stones, fires, water, as well as
physical, living beings like plants, animals, and even human
beings.4 However, the scope of the Fifth Way extends only to
those natural bodies which lack cognitive powers. At the very
least, then, the natural bodies referred to in the Fifth Way
include beings like fires and plants, though some interpreters
also include the functional parts of animals in this category.5 It
is the end-directed actions of these kinds of beings that interest
Aquinas in the Fifth Way. For the sake of simplicity, throughout
the paper I will use the phrases “natural body” and “natural
bodies” to refer only to those natural bodies which are the
subject of the Fifth Way, that is, those which lack cognitive
powers.
Second, questions have rightly been raised concerning the
validity of the Fifth Way, as it appears to fall victim to the
quantifier-shift fallacy.6 To see this one must only note that the
second premise of the argument states that every natural body
must be directed to an end by something intelligent, while the
conclusion seems to suggest that there is one unique
intelligence, God, who directs every natural body to its end.
However, as stated, the premises do not guarantee a unique
intelligence responsible for directing every natural body to its
end. Rather, even if true, the premises seem to leave open the
possibility that there are multiple intelligences responsible for

3

ScG III, c. 2.
II De Anima, lect. 1 (In Aristotelis librum de Anima, ed. A. M. Pirotta [Turin and
Rome: Marietti, 1948], n. 218). See also, STh I, q. 18, a. 1.
5
See, for instance, Reginald Garrigou-Lagrange, God: His Existence and Nature, vol.
1 (St. Louis: Herder Press, 1934); J. J. C. Smart and John Haldane, Atheism and Theism
(Malden, Mass.: Blackwell, 2003), 89; and Lawrence Dewan, “St. Thomas’s ‘Fifth Way’
Revisited,” Universitas 31 (2004): 47-67.
6
This is the main criticism that Anthony Kenny levels against not only the Fifth Way
but each of the Five Ways. See Anthony Kenny, The Five Ways (Notre Dame: University
of Notre Dame Press, 1980).
4

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JOEL JOHNSON

directing natural bodies to their ends—as many intelligences as
there are natural bodies, in fact.
There are two general responses to this problem. First, one
can interpret the premises of the Fifth Way such that, when
sufficiently elucidated, they do guarantee a unique intelligence.7
To do this, one must show that the fact that natural bodies act
for ends does not merely require that there be at least one
divine intelligence, but additionally it requires that there be only
one such intelligence. Second, one can hold that Aquinas’s aim
in the Fifth Way is merely to demonstrate that there is at least
one divine intelligence and that his arguments for the existence
of God’s uniqueness are presented later in his Summa. 8 The
interpretation of the Fifth Way that I defend in this paper suggests that both of these responses have merit. On this interpretation, the line of reasoning that Aquinas presents later in his
Summa to support the uniqueness of God is a simple extension
of the line of reasoning present in the Fifth Way. A fuller
treatment of this response will be developed later in the article.
Finally, it is important to note that even once the validity of
the argument has been established, the Fifth Way does not
purport to demonstrate the existence of a God who possesses all
of the divine-making properties traditionally ascribed to the
God of Christianity. Rather, its purpose is more modest,
namely, to demonstrate the existence of a divine intelligence
that orders the world according to its providence.
I. THE KEY INTERPRETATIVE QUESTIONS
We can now turn to the three most common and, at least
initially, attractive interpretations of the Fifth Way and consider
the key interpretive questions confronting these rival approaches. Although aspects of each of these interpretations will
7

See, for instance, Edward Feser, “Between Aristotle and William Paley: Aquinas’s
Fifth Way,” Nova et vetera (Eng. ed.) 11 (2013): 734-39; and Garrigou-Lagrange, God,
368-74.
8
A fuller treatment of this response can be found in John Wippel, The Metaphysical
Thought of Thomas Aquinas: From Finite Being to Uncreated Being (Washington D.C.:
The Catholic University of America Press, 1999), 485-92.

AQUINAS’S FIFTH WAY

47

ultimately be shown to be problematic, considering them side
by side will both help to clarify the broader issues involved and
serve to motivate the interpretation of the Fifth Way defended
later in the paper.
The primary distinguishing characteristic of these interpretations is their differing understandings of the first premise.
While each agrees that Aquinas’s argument takes as its starting
point the claim that natural bodies act for an end, they disagree
about the precise feature of reality described by this claim. The
three interpretations of the first premise can be stated briefly as
follows:
Intrinsic Finality Interpretation: Some natural bodies, namely, organisms and
their functional parts, act for ends, where the ends are their own preservation
and perfection in being.
Extrinsic Finality Interpretation: Every natural body acts for an end, where the
end is the common good or perfection of the universe.
Final Causality Interpretation: Every natural body acts for an end, where the
end is the determinate effect toward which it is inclined.

The Intrinsic Finality Interpretation is thus called because it
holds that the first premise is based on the observation that
some natural bodies act for their own intrinsic, or individual,
good. The Extrinsic Finality Interpretation takes its name from
the fact that it holds that this premise is concerned with the
observation that natural bodies act for some end extrinsic to
themselves, namely, the common good of the universe. Finally,
the Final Causality Interpretation holds that the first premise of
the Fifth Way is concerned with the more general observation
that natural bodies act for ends at all.
While many commentators provide accounts of the first
premise that fall neatly into one of these three interpretations,
others suggest that the premise can be interpreted as making
claims involving more than one of these interpretations. For
instance, John Haldane, John Kronen, and Sandra Menssen
each in a distinct way suggest that the first premise of the Fifth
Way can be interpreted along the lines of both the Intrinsic

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JOEL JOHNSON

Finality Interpretation and the Extrinsic Finality Interpretation.9
Likewise, at various points in his discussion of the Fifth Way,
Reginald Garrigou-Lagrange suggests that, in addition to being
interpreted in accordance with the Intrinsic Finality Interpretation, the argument can be interpreted along the lines of the
Final Causality Interpretation.10 These commentators appear to
be united in holding that the first premise of the Fifth Way is
ambiguous, and that a valid argument can be constructed on the
basis of more than one of the disambiguated premises. However, even if a valid argument can be constructed on the basis of
all three of these renderings of the first premise, because the
Fifth Way is one argument, not two or three parallel arguments,
and because the Intrinsic Finality Interpretation, Extrinsic
Finality Interpretation, and Final Causality Interpretation must
give rise to distinct arguments, at best only one of these disambiguated premises can represent Aquinas’s intended argument in the Fifth Way.
However, because Aquinas affirms the claims made by each
of these interpretations throughout his corpus, even if at best
only one can be correct, none can be dismissed out of hand.
Instead, their accuracy must be evaluated in relation to the
remainder of the text of the Fifth Way, other similar passages in
Aquinas’s corpus, and his broader philosophical commitments.
The second premise also presents interpretive difficulties.
Aquinas states that the end-directed actions of natural bodies
require the existence of an intellect extrinsic to the natural
bodies, but instead of defending this claim, he presents an
analogy: Natural bodies are directed to an end by a divine
intellect “in the same way that an arrow is directed by an
archer.” While Aquinas makes use of the analogy of the arrow
frequently throughout his works, the relation between
intellectual activity and the end-directed action it attempts to
illuminate is not always obvious. In many passages where the

9
See Smart and Haldane, Atheism and Theism, 89; and John Kronen and Sandra
Menssen, “Hylomorphism and Design: A Reconstruction of Aquinas’s Fifth Way,” The
Modern Schoolman 89 (2012): 155-80.
10
See Garrigou-Lagrange, God, esp. 364.

AQUINAS’S FIFTH WAY

49

analogy is found, he says little to clarify its meaning.11 Rather,
as in the Fifth Way, he seems to assume that its import will be
perspicuous to his readers. However, even in those passages
where he more clearly states its significance, he does not always
do so in the same way. In one set of passages, Aquinas suggests
that the analogy of the archer is meant to illustrate that a
natural agent could not act for some definite effect without
some intellect determining it to that effect.12 In a second set of
passages, Aquinas clarifies this position by additionally suggesting that being determined to a definite effect is a kind of
ordering to that effect, an ordering which only an intellect can
explain.13 Finally, in a third set of passages, he further clarifies
that an intellect is required because the ordering in question
requires knowledge of the end, the means to the end, and the
proportion between means and ends.14
Considering these texts together suggests the following
rudimentary characterization of the analogy: Aquinas invites his
readers to imagine themselves witnessing an arrow fly through
the air and strike a target. He thinks it evident that upon
witnessing this scene one would be justified in believing that the
arrow was shot at the target by an archer, even if the archer
were out of sight. One would be justified in drawing this conclusion because arrows do not by nature possess the necessary
powers, including the necessary intellectual powers, to move
themselves to targets. Thus, if the movement of the arrow to the
target is to be explained, it must be explained by appealing to
an archer who is both aware of the target as an end and
understands the means necessary to move the arrow to it.
Similarly, Aquinas thinks that when we observe natural bodies
acting for ends, we witness beings without cognitive powers
11
See ScG II, c. 23; STh I, q. 23, a. 1; q. 59, a. 1; De Pot., q. 3, a. 11, ad 5; and
V Metaphys., lect. 16 (In duodecim libros Metaphysicorum Aristotelis exposition, ed.
M. R. Cathala and R. M. Spiazzi [Turin and Rome: Marietti, 1950], n. 1000).
12
See ScG III, c. 24; STh I, q. 103, a. 1, ad 3; and STh II-II, q. 90, a. 3.
13
See ScG III, c. 64; STh I-II, q. 1, a. 2; q. 12, a. 5; q. 13 a. 2, ad 3; De Verit., q. 22,
a. 1; I Phys., lect. 15 (Leonine ed., 2:53-54, n. 10); and II Phys., lect. 12 (Leonine ed.,
2:90, n. 1).
14
I Sent. d. 35, q. 1, a. 1; ScG II, c. 23; De Pot., q. 1, a. 5; and q. 3, a. 15.

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JOEL JOHNSON

acting in ways that would be inexplicable were they not moved
to those ends by some intelligence who could grasp both the
ends of natural bodies and the means required to move natural
bodies to such ends. Thus, the analogy suggests that just as we
must explain the movement of the arrow through reference to
an extrinsic intellect (i.e., an archer), so too must we explain the
movements of natural bodies through reference to an extrinsic
intellect (i.e., God).
However, characterized this way, the analogy gives rise to a
further interpretative difficulty. To perceive this difficulty, one
must first recognize that throughout his works Aquinas accepts
the following two theses:
(1) Divine Intelligence Thesis: Natural bodies are directed to their ends by
some divine intelligence, namely, God.
(2) Nature Thesis: Natural bodies are directed to their ends by their very
natures, i.e., their substantial forms and powers.

Our discussion of the analogy of the archer has provided ample
evidence that Aquinas holds the Divine Intelligence Thesis.
However, it is equally evident that he holds the Nature Thesis.
Early in his Summa theologiae, for example, he presents what
seems to be a perfectly naturalistic account of final causality:
“From the form follows [a being’s] inclination to an end or to
action or to something of the sort. For each thing, insofar as it
is in actuality, acts and tends toward that which is suitable to it
according to its form.”15
Underlying the claim that a being’s action for an end follows
upon its form is a broadly Aristotelian metaphysics of powers.16
Aquinas holds that all natural beings, including natural bodies,
possess distinctive powers in virtue of being the bearers of kindspecific substantial forms, and when a natural body acts, it acts
15

STh I, q. 5, a. 5.
For a comprehensive recent study of Aquinas’s metaphysics of powers, see Gloria
Frost, Aquinas on Efficient Causation and Causal Powers (New York: Cambridge
University Press, 2022). For a much briefer summary of Aquinas’s views, see Jeffrey
Brower, “First Principles: Hylomorphism and Causation,” in The New Cambridge
Companion to Aquinas, ed. Eleonore Stump and Thomas Joseph White (New York:
Cambridge University Press, 2022), 31-56.
16

AQUINAS’S FIFTH WAY

51

through the operation of these powers.17 A fire has the power to
heat, water has the power to be heated, a tree has the power to
absorb nutrients from the soil, and so on. In each case, Aquinas
attributes powers to things in order to explain why they
regularly act in ways characteristic of their kinds. Active powers
explain the ways in which a thing regularly acts on other things,
and passive powers explain the ways in which it is regularly
acted upon by other things.18 Furthermore, Aquinas holds that
both of these kinds of powers, insofar as they are powers, are
intrinsically directed or ordered (ordinatur) to an action the
terminus of which is an end, although in different ways.19 The
active powers of a natural body are directed to an end such that
they of themselves give rise to an inclination that determines
their operation for the sake of an end.20 For instance, the active
power by which a fire heats a pot of water is a power inclined
toward producing heat of a determinate temperature. It is not a
power to perform any other kind of action or produce any
other effect, and, in suitable circumstances, a fire will always
perform its characteristic action and produce its characteristic
effect through the operation of this power. Passive powers, in
contrast, are intrinsically directed such that they come to
17

STh I, q. 36, a. 3, ad 1; q. 77, a. 1, ad 3; q. 77, a. 6; q. 5, a. 5; and ScG II, c. 68.
In addition to active powers and passive powers, Aquinas holds that there is a
third kind of power that is both active and passive. See De Virtut., q. 1, a. 1. However,
because these “mixed” powers are all in some measure rational, they are not directly
relevant to the Fifth Way, dealing as it does with beings incapable of cognition, and for
the purposes of this article they can be ignored.
19
STh I, q. 77, a. 3.
20
On the account that I am endorsing here, when Aquinas speaks of a natural body’s
natural inclination to an end, he is speaking of a natural body’s active powers insofar as
these powers are ordered to an action the terminus of which is an end. This ordering to
an action involves possessing an impetus to the end, which explains why active powers
operate whenever the relevant conditions obtain. My view is seemingly at odds with
that of Gloria Frost, who appears to hold that a natural body’s natural inclination to an
end is distinct from its active powers. See Frost, Aquinas on Efficient Causation and
Causal Powers, 125-26. While it is beyond the scope of this article to defend my
account of natural inclinations, it is worth noting that the interpretation of the Fifth
Way I defend below does not depend on my interpretation of the relation between
causal powers and natural inclinations and, mutatis mutandis, is also consistent with
Frost’s account.
18

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JOEL JOHNSON

operate for an end by means of the activity of other beings, that
is, beings with the relevant active powers. Strictly speaking,
passive powers are not inclined toward ends, but disposed toward ends.21 The passive power by which some water is heated
is a power directed toward the end of being heated by an agent
with the power to heat; the power is disposed toward being
heated by something outside of itself which has the power to
heat. Thus, for Aquinas, being ordered to an end is a feature of
a power qua power; it is impossible for a power to be a power
without being so directed. In virtue of its active powers, a
natural body is inclined toward ends, and in virtue of its passive
powers, it is disposed to be moved toward ends. Aquinas holds
that the end-directed actions of all natural bodies are explained
by the intrinsically directed powers that they possess in virtue of
being the kinds of things that they are.22
The fact that Aquinas accepts both the Divine Intelligence
Thesis and the Nature Thesis might lead one to think that his
account of end-directedness suffers from overdetermination. 23
He appears to hold that both a divine intellect and a natural
body’s nature explain the exact same phenomenon, namely, a
natural body’s directedness toward an end. However, Aquinas is
21

For recent discussions of Aquinas’s account of passive powers, see Gloria Frost,
“Aquinas on Passive Powers,” Vivarium 59 (2021): 33-51; and Frost, Aquinas on
Efficient Causation and Causal Powers.
22
It is noteworthy that when Aquinas argues that natural bodies “act” for an end in
the Fifth Way, he uses the Latin term operantur to denote their activity. Elsewhere in his
corpus, Aquinas regularly uses operantur to refer to the operation of both active and
passive powers, and thus it is a mistake to think that the end-directed activity at issue in
the Fifth Way is limited to the actions of natural agents or efficient causes. Patients,
through the operation of their passive powers, also act (operantur) for an end, though
only through the influence of some efficient cause.
23
Stephan Schmid, “Teleology and the Dispositional Theory of Causation in Thomas
Aquinas,” Logical Analysis and History of Philosophy 14 (2011): 21-39 argues just this
point. Schmid argues that there is tension between Aquinas’s dispositionalist theory of
end-directed action—his account of end-directed action as being consequent upon
substantial forms and powers—and his claim that God explains end-directedness. On
Schmid’s account, God cannot account for the end-directed actions of natural beings
without robbing them of their own intrinsic directedness to their ends. One of the goals
of this paper is to show that there is nothing in Aquinas’s texts that requires attributing
to him this inconsistency.

AQUINAS’S FIFTH WAY

53

able to avoid the charge of overdetermination by holding a third
thesis:
(3) Creation Thesis: God directs natural bodies to their ends by creating them
with natures directed to those ends.

That Aquinas accepts the Creation Thesis is no less clear than
that he accepts the other two theses. For example, in his “treatise on divine government” in his Summa theologiae, he claims
that the natures of things are a kind of impression (impressio)
from God, and the means by which God directs things to their
ends is by creating them with natures directed to those ends.24
Similarly, in his Summa contra gentiles, he argues that every
operation of a power is consequent upon some form, so the
cause of motion must be God, who has given to things their
forms.25 Clearly, there is no overdetermination in claiming that
natural bodies are directed to their ends by their natures, while
at the same time being directed to their ends by God, who
creates and sustains their natures.
Nevertheless, beyond clarifying why he cannot be charged
with overdetermination, Aquinas’s acceptance of the Creation
Thesis is largely irrelevant to one’s interpretation of the Fifth
Way. The Creation Thesis assumes the existence of God, which
is precisely what the Fifth Way attempts to demonstrate, and
thus interpreters of the Fifth Way cannot assume this thesis in
their defenses of the argument. Moreover, because the Creation
Thesis cannot be assumed, the fact that Aquinas accepts both
the Nature Thesis and the Divine Intelligence Thesis presents
interpreters with a difficulty. All of the Five Ways—and, indeed,
all of Aquinas’s arguments for the existence of God—take the
form of quia demonstrations.26 That is, they purport to demonstrate the existence of God by showing that some observed
effect can be explained only by a being with one or more of the
divine attributes. In the Fifth Way, the observed effect is that
natural bodies act for ends, and the argument proceeds by
24

STh I, q. 103, a. 1, ad 3.
ScG III, c. 67.
26
STh I, q. 2, a. 2.
25

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JOEL JOHNSON

claiming that such actions can only be explained by some divine
intelligence. However, given that Aquinas accepts the Nature
Thesis, interpreters of the Fifth Way face the difficulty of
explaining how he justifies the claim that only a divine intelligence can explain a natural body’s action for an end. In
other words, given that Aquinas accepts that natural bodies are
directed to their ends in virtue of possessing substantial forms
and powers, it is not clear why he also holds that a divine
intelligence is needed to explain their end-directed actions.
To respond to this difficulty, interpretations of the Fifth Way
must meet what I call the Quia Demonstration Condition:
Quia Demonstration Condition: To be successful, any interpretation of the
Fifth Way must show how, on Aquinas’s own account, the end-directed
actions of natural bodies are not completely explained by their intrinsic
principles, namely, their substantial forms and powers, but further require
explanation in terms of a divine intelligence.

We can elucidate the rationale behind the Quia Demonstration
Condition by once again considering the analogy of the arrow.
As Aquinas himself suggests, a key feature of the analogy is that
the arrow by nature lacks the powers necessary to move itself to
the target.27 It is only because it lacks these powers that it is
obvious to an observer that the arrow is directed to the target
by an archer. If, however, we inhabited a world where arrows
by nature possessed the powers necessary to direct themselves
to targets, then, upon seeing an arrow strike a target, an onlooker would not be justified in thinking that an arrow was shot
by an archer. Likewise in the case of natural bodies, if the
intrinsic principles of natural bodies were sufficient to explain
their end-directed activity, then there would be no reason to
think that they were directed to their ends by a divine
intelligence. Thus, it is necessary for interpreters of the Fifth
Way to meet the Quia Demonstration Condition by identifying
some feature or aspect of the end-directed activity of natural
bodies that requires a divine intellect and not merely a nature.

27

STh I, q. 23, a. 1.

AQUINAS’S FIFTH WAY

55

II. THREE INTERPRETATIONS OF THE FIFTH WAY
A) The Intrinsic Finality Interpretation
With this understanding of the key interpretative issues in
place, we can begin our discussion of the common interpretations of the Fifth Way by considering the view I have
labeled the Intrinsic Finality Interpretation.
On the Intrinsic Finality Interpretation, endorsed by such
thinkers as Reginald Garrigou-Lagrange, Lawrence Dewan, and
John Haldane,28 the first premise is understood as referring to
the fact that at least some natural bodies, namely, organisms, are
equipped with functional parts through which they act for their
own preservation and perfection in being. 29 Dewan, for instance, compares the phenomenon referenced in the first premise of the Fifth Way to the irreducibly complex systems
discussed by Michael Behe. 30 Likewise, Haldane suggests that
the subject of the first premise is the “apparent purpose in the
organization and activity of living things,” 31 and GarrigouLagrange states that the first premise “concerns the intrinsic
finality observed in the activity of beings which, taken separately, lack intelligence. For instance, the eye is for seeing, and
wings for flying.”32 Common to all of these interpretations is
the claim that not only do living things act for ends which are
good for them, but that their so acting is a consequence of their
parts being organized or ordered to attain those ends.
The Intrinsic Finality Interpretation interprets the second
premise of the Fifth Way as advancing the claim that the
28

As mentioned above, Garrigou-Lagrange and Haldane also endorse other
interpretations of the Fifth Way (the Final Causality Interpretation and the Extrinsic
Finality Interpretation, respectively). However, both thinkers primarily focus on
observations involving intrinsic finality in their discussions of the Fifth Way.
29
Dewan, “St. Thomas’s ‘Fifth Way’ Revisited”; Smart and Haldane, Atheism and
Theism; Garrigou-Lagrange, God.
30
Dewan, “St. Thomas’s ‘Fifth Way’ Revisited,” 58. See also, Michael J. Behe,
Darwin’s Black Box: The Biochemical Challenge to Evolution (New York: Free Press,
2001).
31
Smart and Haldane, Atheism and Theism, 89.
32
Garrigou-Lagrange, God, 347.

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JOEL JOHNSON

explanation for this ordering among the functional parts of an
organism must be some intelligence extrinsic to the organism.33
The argument supporting this premise is a familiar one: If there
exists a real and not merely apparent order among things, there
must be some explanation for that order. There exists a real
order among the functional parts of organisms, and so there
must be some explanation for this order. Now, two explanations are possible: chance and intelligence. However, given that
these functional parts operate, always or for the most part, for
the good of the organism, the order among them cannot exist
by chance but must be the result of some intelligence.
Therefore, there must be some intelligence responsible for the
ordering among the functional parts of organisms. Moreover,
this intelligence cannot be found in the functional parts of
organisms, because these functional parts lack intelligence.
Likewise, this intelligence cannot be found in the whole
organism, because the whole organism is unable to determine
for itself the ordering of its functional parts. Therefore, this
intelligence must be extrinsic to the organism.
Much could be said about the merits of this kind of
argument, but the question before us is not whether this is a
good argument, but whether it is the argument of the Fifth
Way. The first thing to note in evaluating this argument as an
interpretation of the Fifth Way is that its claims are consistent
with claims Aquinas makes elsewhere in his corpus. Aquinas
clearly holds both that the functional parts of an organism are
ordered to the good of the whole organism and that, in general,
order requires an intellect.34
Furthermore, although not explicitly addressed by its
defenders, this interpretation is capable of meeting the Quia
Demonstration Condition. To do so, defenders of this interpre33

Dewan, “St. Thomas’s ‘Fifth Way’ Revisited,” 64, Garrigou-Lagrange, God,
367-72.
34
For evidence that Aquinas holds that organisms possess the kind of intrinsic order
that the Intrinsic Finality Interpretation attributes to them, see De Verit., q. 5, a. 2; ScG
III, c. 3; STh I, q. 65, a. 2; and II Phys., lect. 13 (Leonine ed., 2:93, n. 5). Moreover, in
De Verit., q. 5, a. 2; and II Phys., lect. 14 (Leonine ed., 2:96, n. 8), Aquinas suggests that
this order requires a divine intellect.

AQUINAS’S FIFTH WAY

57

tation can argue that the natures of living beings explain their
end-directed activities, but a further explanation is required for
the existence of beings that possess these kinds of natures. The
account would go something like this: The natures of living
beings exhibit a kind of ordered complexity. The powers they
possess consequent upon their substantial forms are ordered
both hierarchically, such that one power is ordered to another,
and complementarily, such that the powers complement one
another. Furthermore, it is in virtue of these ordered natures
that organisms are able regularly to act for and to attain their
ends. However, because such ordered natures do not explain
themselves, a further explanation is required, and this further
explanation is a divine intellect. Thus, an organism’s nature and
the divine intelligence explain two different features of its enddirected activity. Its nature explains why the organism is
directed to an end, and a divine intelligence explains why the
organism’s nature exhibits the order required for it to be so
directed.
However, despite its strengths, there is a significant textual
reason for thinking that the Intrinsic Finality Interpretation
does not accurately capture the argument of the Fifth Way. To
begin, a natural reading of the first premise of the Fifth Way
does not suggest that Aquinas is speaking only of living beings.
The natural reading of his claim that “some things lacking
cognition, namely, natural bodies, act for an end,”35 is that he is
referring to all natural bodies that lack cognition, not merely
organisms and their functional parts. Moreover, in the
conclusion, Aquinas claims that the Fifth Way has demonstrated
“something with intelligence by which all natural things are
ordered toward an end.”36 The conclusion that all natural things
are ordered toward an end does not follow from the premise
that some natural bodies, namely, living beings, are ordered to
an end. By limiting the scope of the Fifth Way to just organisms

35
STh I, q. 2, a. 3: “Videmus enim quod aliqua quae cognitione carent, scilicet
corpora naturalia, operantur propter finem.”
36
Ibid.: “Ergo est aliquid intelligens, a quo omnes res naturales ordinantur ad
finem.”

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JOEL JOHNSON

and their functional parts, the Intrinsic Finality Interpretation is
unable to account for the Fifth Way’s strong conclusion.
It may be objected that this is a problem for any interpretation of the Fifth Way, not just the Intrinsic Finality Interpretation. For even if one interprets the first premise broadly to
include all natural bodies that lack cognition, one cannot account for the stronger conclusion which refers to all natural
things, due to the fact that some natural things possess
cognition. While this response contains some truth, those who
interpret the first premise more broadly have a more plausible
response than defenders of the Intrinsic Finality Interpretation.
First, they could hold that the phrase “all natural things” in the
conclusion refers only to those natural bodies that lack cognition. Second, and more plausibly, they could hold that it
refers to all natural things insofar as they are natural, that is,
insofar as they possess natural inclinations and dispositions to
ends, inclinations and dispositions that are not consequent on
some apprehended form. Either of these responses is more
credible than claiming that “all natural things” refers merely to
organisms and their functional parts.
B) The Extrinsic Finality Interpretation
While more could be said about the Intrinsic Finality
Interpretation, our discussion thus far is sufficient to show that
it faces a serious textual difficulty. We can now turn our attention to the Extrinsic Finality Interpretation. Like the Intrinsic
Finality Interpretation, the Extrinsic Finality Interpretation
holds that the basic structure of the Fifth Way concerns the
ordering of parts to wholes and the need for a divine intellect to
explain such ordering. However, in contrast to the Intrinsic
Finality Interpretation, the Extrinsic Finality Interpretation
interprets the first premise of the Fifth Way as referring not to
the ordering of functional parts of organisms to the preservation
and perfection of whole organisms, but rather to the ordering of
all natural bodies to the preservation and perfection of the
whole universe. Given that it interprets the first premise as
applying to all natural bodies, the Extrinsic Finality Interpre-

AQUINAS’S FIFTH WAY

59

tation avoids the chief textual problem facing the Intrinsic
Finality Interpretation.
The most philosophically sophisticated version of this interpretation is advanced by Jacques Maritain in his book Approaches to God. 37 Maritain introduces the Fifth Way by
describing the observation on which he thinks the first premise
is based:
It is a fact that in this universe, myriads of beings exist and act, but neither
know nor think. And it is a fact that the activities of these beings follow
regular courses, which are translated into the laws that our science establishes,
and which give rise to recurrences of constant periodicity. . . . Whether one
considers the actions which they exert upon one another or the general
movement of their history, things are thus seen to be engaged in a system of
regular relations and oriented in a stably defined direction.38

Maritain goes on to say that the continued existence of this
“system of regular relations” or “ordered multitude” requires
that the beings that are part of this system are directed toward
maintaining it in existence. 39 Thus, as Maritain interprets the
first premise of the Fifth Way, Aquinas’s argument begins with
the observation that natural bodies have as their end participating in and contributing to the order or common good of the
universe, and he supports this observation with the claim that
the order of the universe could not be so preserved unless its
parts were so directed.
Maritain’s interpretation of the second premise is less clear
than his interpretation of the first. He appears to justify this
premise using an argumentative move typical of “fine-tuning”
arguments. He argues that if we take seriously the claim that
beings without cognition are ordered to the common good of
the universe, we need an explanation for this fact. He holds that
only two explanations are possible: chance or intelligence.
37

Jacques Maritain, Approaches to God (New York: Harper Brothers, 1954). As
mentioned earlier, Haldane, Kronen, and Menssen also suggest that the Fifth Way can
be interpreted along the lines of the Extrinsic Finality Interpretation, though they do
not develop their own versions of this interpretation.
38
Ibid., 58.
39
Ibid., 65.

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JOEL JOHNSON

Using an argument of his own—not Aquinas’s—he dismisses
chance as a possible explanation and concludes that the explanation must be intelligence.40
Like the Intrinsic Finality Interpretation, the Extrinsic
Finality Interpretation attributes to Aquinas positions that he
does, in fact, hold. For instance, consonant with the Extrinsic
Finality Interpretation’s reading of the first premise, Aquinas
argues that the order exhibited by things in the universe is
evidence that things are directed toward maintaining this
order. 41 He suggests that for goodness to be produced in the
universe as a whole, not only must individual beings be directed
to their own individual ends, but also the ends of individual
beings must complement the ends of other individual beings.
For example, he notes that while heat contributes to the good
of the universe as a whole by breaking beings down “up to a
certain point and in a certain way,”42 if heat, or hot things like
fires, broke down other beings without limit, then the order of
the universe would be upset. That these effects do not occur, or
do not occur regularly, shows that beings within the universe
are fundamentally ordered to the common good of the universe.
Similarly, the Extrinsic Finality Interpretation’s gloss on the
second premise also attributes to Aquinas a position that he, in
fact, holds. For instance, in the Summa contra gentiles, Aquinas
argues that in order for diverse things to be ordered to a
common end, they must be ordered by an intelligence that both
knows the common end and the relations between the things
ordered to the end.43
Moreover, although Maritain does not explicitly address the
Quia Demonstration Condition, a response is implicit in his
defense of the second premise. The general form of this
response is that while the natures of natural bodies can explain
their inclinations toward their own individual ends, they cannot
explain how the ends of the many diverse beings that compose

40

Ibid., 61-64.
De Verit., q. 5, a. 2.
42
Ibid.
43
ScG II, c. 24.
41

AQUINAS’S FIFTH WAY

61

the universe are ordered so as to promote the perfection of the
universe as a whole. In order to explain this second feature of
the world, appeal must be made to a divine intelligence.
Nevertheless, as was the case with the Intrinsic Finality
Interpretation, although Aquinas does hold the positions that
the Extrinsic Finality Interpretation attributes to him, there is
reason to believe that these are not the positions on which the
Fifth Way rests. The most significant difficulty is noted by
Lawrence Dewan, who argues that a close reading of book III,
chapter 64 of Aquinas’s Summa contra gentiles undermines this
interpretation.44 In this passage, Aquinas gives several arguments
for the claim that God governs the world through his providence. One of these arguments is similar in structure to the
Fifth Way, although instead of attempting to demonstrate God’s
existence it attempts to prove God’s providence. Aquinas
writes:
It is proved that natural bodies are moved and act for an end—even though
they do not know the end—from the fact that what happens to them is
always, or often, what is best; and, they would not be accomplished differently if they were done by means of art. But it is impossible for things that
do not know their end to act for the end, and to arrive at the end in an
orderly way, unless they are moved by someone who has knowledge of the
end, as an arrow is directed to the target by the archer. Therefore, the whole
working of nature must be ordered by knowledge in some way. And, indeed,
either directly or indirectly, this must lead back to God, since every lower art
and type of knowledge must receive its principles from a higher one, as we
also see in the theoretical and practical sciences. Therefore, God governs the
world by his providence.45

44

Dewan, “St. Thomas’s ‘Fifth Way’ Revisited.”
ScG III, c. 64: “Probatum est quod corpora naturalia moventur et operantur
propter finem, licet finem non cognoscant, ex hoc quod semper vel frequentius accidit
in eis quod melius est; et non aliter fierent si fierent per artem. Impossibile est autem
quod aliqua non cognoscentia finem operentur propter finem et ordinate perveniant in
ipsum nisi sint mota ab aliquo habente cognitionem finis: sicut sagitta dirigitur ad
signum a sagittante. Oportet ergo quod tota operatio naturae ab aliqua cognitione
ordinetur. Et hoc quidem vel mediate vel immediate oportet reducere in Deum: oportet
enim quod omnis inferior ars et cognitio a superiori principia accipiat, sicut etiam in
scientiis speculativis et operativis apparet. Deus igitur sua providentia mundum
gubernat” (Leonine ed., 14:179).
45

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JOEL JOHNSON

It is clear that this argument follows from the same observations
referred to in the Fifth Way. In both cases, Aquinas notes that
natural bodies act for an end and this would not be possible
without a divine intellect directing them to their end. Dewan
juxtaposes this argument with a second argument Aquinas
makes immediately following the first:
Things that are different according to their natures do not come together in
one order unless they are assembled into a unity by someone who orders
them. But in the universe things are distinct and possess contrary natures; yet
all come together in one order, and while some give assistance to others, there
are also some that are served or ruled over by others. Therefore, there must be
one orderer and governor of the universe.46

While there is some ambiguity about the kind of enddirectedness at play in the first argument, this second argument
is clearly concerned with the ordering of individual beings to a
common end. Thus, Dewan’s criticism of the Extrinsic Finality
Interpretation is that these are two distinct arguments and the
Extrinsic Finality Interpretation confuses the first argument for
the second.47 On the reasonable assumption that Aquinas would
not present two essentially identical arguments in the same
passage, it follows that the first argument in this passage must
take as its starting point something other than the ordering of
beings to the common good of the universe. Moreover, due to
the similarities between the first argument and the Fifth Way,
the Fifth Way, too, must not be based on such ordering.
Although textual arguments of this sort are difficult to settle
conclusively, I suggest that this argument provides a convincing
reason for rejecting the Extrinsic Finality Interpretation.

46

Ibid.: “Ea quae sunt secundum suam naturam distincta, in unum ordinem non
conveniunt nisi ab uno ordinante colligantur in unum. In universitate autem rerum sunt
res distinctas et contrarias naturas habentes, quae tamen omnes in unum ordinem
conveniunt, dum quaedam operationes quorundam excipiunt, quaedam etiam a
quibusdam iuvantur vel imperantur. Oportet igitur quod sit universorum unus ordinator
et gubernator” (Leonine ed., 14:179).
47
Dewan, “St. Thomas’s ‘Fifth Way’ Revisited,” 56.

AQUINAS’S FIFTH WAY

63

C) The Final Causality Interpretation
Having considered the difficulties encountered by the first
two interpretations, we can now turn to the last of the common
interpretations of the Fifth Way, what I have labeled the Final
Causality Interpretation. The Final Causality Interpretation has
been advanced by a number of thinkers, most prominently John
Wippel and Edward Feser.48 While there are slight differences
in approach and emphasis between these thinkers, they interpret
both premises in much the same way. Common to their interpretations is the claim that the Fifth Way is not, strictly
speaking, a design argument. Design arguments, like the Intrinsic Finality Interpretation and the Extrinsic Finality Interpretation, seek to argue from some order present in nature to the
existence of some intelligence responsible for the order. In
contrast, the Final Causality Interpretation holds that the Fifth
Way seeks to prove the existence of God on the basis of
directedness itself. That is, it holds that the observation on
which the Fifth Way is based is not that natural bodies act for
the sake of some individual or common good, but rather that
natural bodies are directed toward ends at all. Moreover,
because on this view all natural bodies are directed toward
ends, the Final Causality Interpretation also avoids the textual
problem faced by the Intrinsic Finality Interpretation.
According to defenders of the Final Causality Interpretation,
the Fifth Way’s first premise refers to the observation that
natural bodies exhibit what they call “finality.”49 That is, natural
bodies “inherently or of their nature ‘point to’ their characteristic effects as to an end.”50 What does it mean for a natural
48
See Wippel, Metaphysical Thought of Thomas Aquinas, 480-85; and Feser,
“Between Aristotle and William Paley,” 707-9. Similar interpretations are also defended
by William Newton, “A Case of Mistaken Identity: Aquinas’s Fifth Way and Arguments
of Intelligent Design,” New Blackfriars, 95, no. 1095 (2014): 569-78; and Gavin Kerr,
“Design Arguments and Aquinas’s Fifth Way,” The Thomist 82 (2018): 447-71.
49
Wippel, Metaphysical Thought of Thomas Aquinas, 480; Feser, “Between Aristotle
and William Paley,” 726; and Kerr, “Design Arguments and Aquinas’s Fifth Way,” 451
and 468.
50
Feser, “Between Aristotle and William Paley,” 726.

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JOEL JOHNSON

body to “point to” its characteristic effect? In the context of
Aquinas’s natural philosophy, we can locate this understanding
of finality in the active powers of things.51 As we saw in our
earlier discussion of the Nature Thesis, Aquinas holds that in
virtue of possessing kind-specific substantial forms, beings also
possess powers that “point to,” or are intrinsically directed to,
effects characteristic of their kinds. Feser suggests that this
account of powers and ends is broadly analogous to the accounts of powers and their manifestations given by contemporary causal powers theorists. 52 Where Aquinas speaks of
powers and ends, contemporary theorists speak of dispositions
and manifestations. Just as dispositions “point to” their manifestations, so too do powers “point to” their characteristic
effects, or ends.
Defenders of this interpretation are clearly correct in holding
that Aquinas believes that natural bodies exhibit finality on the
basis of their intrinsic principles, as our earlier discussion of the
Nature Thesis has shown. The chief task confronting the Final
Causality Interpretation lies in defending its interpretation of
the second premise, that is, providing evidence for the claim
that Aquinas holds that a divine intelligence is necessary for
natural bodies to exhibit finality. To see that this task might
prove difficult, one must only recall our earlier discussion of the
Quia Demonstration Condition, where we saw that for the Fifth
Way to succeed as a quia demonstration there must be some
feature of end-directed activity that can only be caused or
explained by God, and not merely by a being’s nature. Thus, for
the Final Causality Interpretation to succeed, it must show why
a natural body’s nature cannot completely explain its inclination
51
To my knowledge, none of the defenders of the Final Causality Interpretation
distinguish between the manner in which active powers point to their ends—i.e., they
are inclined to their ends—and the manner in which passive powers do so—i.e., they are
disposed to be moved to ends by some agent. Instead, they appear to focus exclusively
on the inclinations of natural bodies, that is, on the ordering of the active powers of
natural bodies to their ends. Therefore, in my discussion of this interpretation I also
focus exclusively on the inclinations of natural bodies, even though the Fifth Way is not
concerned only with this kind of directedness (see n. 22).
52
Feser, “Between Aristotle and William Paley,” 747-48.

AQUINAS’S FIFTH WAY

65

toward an end and why a natural body’s “pointing to” its
characteristic effect requires further explanation in terms of a
divine intellect. In what follows, I will argue that defenders of
the Final Causality Interpretation fail in this task.
With this in mind, let us turn to the two arguments that
Wippel and Feser between them employ to support the claim
that a divine intellect is necessary for things to possess natures
that are directed toward ends.53 The first argument is defended
by both Wippel and Feser. It begins with the claim that being
directed toward an end requires some cognition of the end.
Wippel and Feser support this claim by arguing that in order for
an agent to direct its action toward an end, the end must be the
cause of the agent’s action, and in order for the end to be the
cause of the action, it must influence the agent in some way.
Moreover, they argue that because the end does not exist in
reality prior to the action of the agent—in many cases, the agent
acts to bring the end into existence—the only way that the end
can influence an agent is if it exists in an intellect. On their
view, the paradigm case of an end influencing the action of an
agent by means of an intellect occurs in voluntary human
action. A human being possesses powers of intellect and will
and by means of these powers is able to apprehend the end he
wants to attain prior to acting and then to direct his actions
toward achieving it. Wippel and Feser believe that the same
53

In addition to the two arguments marshalled by Wippel and Feser, Kerr (“Design
Arguments and Aquinas’s Fifth Way”) employs a third argument for the Final Causality
Interpretation. Kerr argues that natural bodies do not possess their finality of
themselves, so to explain how they are directed toward ends, we must understand them
as being members of an essentially ordered causal series. Moreover, if they are members
of an essentially ordered causal series, then there must be some primary cause of that
series that explains the end-directedness of each member of the series. Therefore, Kerr’s
reasoning seems to go, the primary cause of the essentially ordered series must be some
intelligence responsible for the end-directedness of each member of the series. However,
while Kerr’s discussion of essentially ordered causal series succeeds in illuminating the
Creation Thesis—that is, it succeeds in clarifying Aquinas’s account of how God directs
natural bodies to their ends—he is unable to demonstrate that God directs them to their
ends. The chief problem with the argument is that Kerr overlooks the fact that Aquinas
accepts the Nature Thesis, that is, that Aquinas holds that natural bodies do possess
finality of themselves.

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relation between cognition and end-directedness must hold
more broadly, including in the case of natural bodies. They
argue that because a natural body does not possess cognitive
powers of its own, the end of a natural body cannot influence
its action by existing in its own intellect, but rather must exist in
the intellect of some divine intelligence. Thus, they conclude
that there must be some agent who directs natural bodies to
their ends by impressing on them inclinations that are directed
to those ends. 54 Wippel expresses the essence of his understanding of the second premise as follows:
An agent does not act in a given way unless it is influenced by an end. Noncognitive agents cannot explicitly know their ends. Hence the only way of
accounting for the ability of an end to influence such an agent is to appeal to
an inclination that is impressed upon that agent by an intelligent being.55

Thus, Wippel and Feser hold that if a divine intelligence did not
impress on a natural body an inclination to an end, then the
natural body would not incline toward the end and, hence,
would not act for the end. Given that natural bodies do act for
ends, Wippel and Feser hold that there must exist some divine
intellect directing them to their ends.
There are two closely related problems with this argument.
First, neither Wippel nor Feser provides textual support for the
key claim that the influence that an end has on an agent can
only be explained by some cognition of the end. Wippel admits
that this line of reasoning is not explicitly found in Aquinas’s
texts, while Feser attributes the argument to “Scholastic
philosophers,” not to Aquinas himself.56 Second, in many pas54

Feser, “Between Aristotle and William Paley,” 736; Wippel, Metaphysical Thought
of Thomas Aquinas, 484-85.
55
Wippel, Metaphysical Thought of Thomas Aquinas, 483-84; see also, Feser,
“Between Aristotle and William Paley,” 733-35.
56
Wippel, Metaphysical Thought of Thomas Aquinas, 483; and Feser, “Between
Aristotle and William Paley,” 734. To my knowledge, Robert Pasnau presents the
lengthiest defense of the claim that, according to Aquinas, the only way that an end can
causally influence an agent is by means of some cognition of the end. However, Pasnau’s
defense relies on weak textual evidence. His argument consists of showing that Avicenna
and Scotus accept the claim and, on this basis alone, suggesting that Aquinas accepts it as

AQUINAS’S FIFTH WAY

67

sages where one would expect Aquinas to claim that a being’s
inclination toward an end must always be caused by some
cognition of the end, he instead claims that a being’s inclination
toward an end is always consequent upon some form. Furthermore, he clearly states that it is only in cases of voluntary action
that this form must be an apprehended form; in cases of natural
action, an agent is inclined toward an end consequent upon its
substantial form and active powers.57 These texts coincide with
those cited in our earlier discussion of the Nature Thesis, where
we saw that Aquinas possesses an account of how natural bodies
incline toward ends which does not rely on cognition but on the
intrinsically directed powers that they possess as bearers of their
substantial forms. The end of the action causes the action—it
influences or explains the action—because it is the determinate
effect toward which the agent, through its powers, is inclined.
The influence that an end exerts on an agent is found in the
very structure of the active powers of natural bodies, which are
always directed to some end.58 On this account, no cognition,
on the part of either a natural body or something extrinsic to
the natural body, appears to be necessary. Thus, Wippel and
Feser’s argument in support of the second premise does not
succeed in showing that a divine intellect is necessary for finality. The feature of reality that they argue needs to be
explained by God, Aquinas himself suggests can be explained by
substantial forms and active powers.
The second argument used to justify the second premise is
presented by Feser alone. He begins his argument by
well. See Robert Pasnau, “Intentionality and Final Causes,” in Ancient and Medieval
Theories of Intentionality, ed. Dominik Perler (Boston: Brill, 2001), 301-23.
57
See, for instance, ScG III, c. 3; STh I, q. 5, a. 5; and STh I-II, q. 8, a. 1, ad 1.
58
Of particular relevance to one’s evaluation of Wippel and Feser’s argument is
STh I-II, q. 8, a. 1, ad 1, where Aquinas claims that the end of an action causes an
action by preexisting in the intention of the agent (in intentione agentis). Although
Aquinas writes this in the context of human action, taking “in intentione agentis” to
mean more broadly “in the natural inclination of the agent,” it is an equally valid
response in the context of natural bodies. This interpretation of the passage should be
particularly amenable to defenders of the Final Causality Interpretation, as they
interpret ex intentione as it appears in the Fifth Way as “on the basis of some natural
inclination.”

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referencing the following passage from the Summa contra
gentiles:
Things can be ordered only by knowing their relation and proportion to one
another, and to something higher, which is their end; for the order of certain
things to one another is for the sake of their order to an end. But only a being
endowed with intellect is capable of knowing the mutual relations and
proportions of things; and to judge of certain things by the highest cause is the
prerogative of wisdom. All ordering, therefore, is necessarily effected by
means of the wisdom of a being endowed with intelligence.59

While acknowledging that this passage could be used to support
design-type interpretations of the Fifth Way, Feser holds that it
can also be used to support the Final Causality Interpretation.
He makes use of this passage to argue, in a way similar to that
of design arguments, that a divine intelligence must exist to
account for order. However, unlike ordinary design arguments,
the order Feser suggests is involved in the second premise of the
Fifth Way is the order between a single natural body considered
individually and its typical effect. He uses the example of fire,
suggesting that “fire . . . can ‘point to’ heat as its typical effect
only if an intellect fits the former to the latter as an appropriate
means to the latter.” 60 He defends this suggestion by further
claiming that “whatever relates [fire and heat] in this law-like
way must be capable of grasping their natures and relations in
the abstract, and something capable of such abstraction just is
something with an intellect.” 61 While Feser does not develop
either of these claims, he could be making one of two different
arguments. First, he could be arguing that a fire’s directedness
toward heat is a contingent feature of the fire, and therefore
some intellect is required to explain why a fire is inclined
toward an effect that is appropriate for it, like heat, and not one
that is inappropriate for it, like cold. Second, he could be
suggesting that being directed to any effect at all, appropriate or
59
ScG II, c. 24. In order to represent Feser’s argument most accurately, I have used
James F. Anderson’s translation of this text as cited in Feser, “Between Aristotle and
William Paley,” 735.
60
Feser, “Between Aristotle and William Paley,” 736.
61
Ibid.

AQUINAS’S FIFTH WAY

69

inappropriate, is a kind of ordering, and this ordering like any
other must be explained in terms of an intellect.
Let us evaluate each of these possibilities in turn. The first
gloss on Feser’s argument is problematic because it requires that
the relation between fire and heat be a contingent one, when on
Aquinas’s view it is not. For Aquinas, being directed toward
producing heat is an essential feature of what it is to be a fire. In
other words, a thing cannot possess the substantial form of a
fire without also possessing an active power directed toward
producing heat. Aquinas is clear that the active powers of a
substance are essential principles of the substance; they are
propria that “flow from” (fluant ab) its substantial form.62 Now,
Aquinas thinks that God can give a thing powers in addition to
those it possesses by nature without changing its essence,63 and
it seems reasonable to hold that God can also impede a fire
from exercising its power to heat without changing its essence.
However, given that possession of the power to heat is an
essential principle of a fire, even God could not remove this
principle without changing its essence.64 And because a natural
body and its active powers are related essentially, not contingently, it makes no more sense to say that it is appropriate
that a fire is directed toward heat than it does to say that it is
appropriate that water is H2O. In both cases, the concept of
appropriateness does not apply. There is, therefore, no reason
to think that a divine intellect is necessary for a natural body to
be directed to its characteristic effect. Thus, the first gloss on
Feser’s argument does not succeed in justifying the second
premise of the Fifth Way.
But what about the second gloss on Feser’s argument? Does
the fact that a natural body points to its characteristic effect
require that it be ordered to that effect by an intellect, even if its
62

STh I, q. 77, a. 6. Also, see De Pot., q. 5, a. 7, where Aquinas states that because
active and passive powers are proper accidents of the elements, they must be caused by
the essential principles of the elements.
63
For instance, Aquinas suggests that God can give fire the power to cleanse the
world in addition to the power to heat, without changing the essence of fire. See STh
Suppl., q. 74, a. 3, ad 2.
64
De Pot., q. 5, a. 7.

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JOEL JOHNSON

pointing to the effect is essential to it? While it is difficult to
answer this question with confidence, there are convincing
reasons to think it does not, especially in the context of
Aquinas’s thought. To begin, the text on which Feser’s argument is based does not support attributing to Aquinas the view
that “pointing to” an effect is a kind of ordering. In the passage
that immediately follows the text quoted by Feser, Aquinas uses
the example of an architect to illustrate his claim that “things
can be ordered only by knowing their relation and proportion
to one another, and to something higher, which is their end.”
By choosing the example of an architect, Aquinas suggests that
it is the design and order among diverse things that requires an
ordering intellect. Thus, the natural reading of the text suggests
that the line of reasoning quoted by Feser properly applies to
the argument that the Extrinsic Finality Interpretation mistakenly attributes to the Fifth Way. Nothing in this passage
supports attributing to Aquinas the view that the mere
directedness of powers is a kind of ordering.
In addition to being unsupported by the text, there are other
reasons for thinking that “pointing to” an effect does not
require an ordering intellect. To begin, while it may be clear
that a natural body that is ordered to some effect will “point to”
that effect, it is not clear that the converse is true. That is, it is
not clear that merely pointing to an effect requires being
ordered to that effect. Rather, as Aquinas himself states in the
passage quoted by Feser, ordering includes the further notions
of mutual relations and proportions. To say that some means is
ordered to some end suggests that, in addition to pointing
toward the end, it is also appropriately proportioned to
attaining the end. But if merely pointing to an end is not a
sufficient condition for a thing to be ordered to the end, then
the fact that an active power points toward an end is not
sufficient to show that it is ordered to the end. Rather, what
would need to be shown is that the active power somehow
exhibits an appropriate proportion to that effect. Now, designtype interpretations of the Fifth Way are capable of showing
that an active power exhibits this kind of proportion to its
effect, because these arguments take the effect to be something

AQUINAS’S FIFTH WAY

71

that can only be achieved if multiple powers are proportioned
and coordinated with respect to each other. On the Intrinsic
Finality Interpretation, a living being’s powers must be coordinated in order to achieve the good of the organism, and on
the Extrinsic Finality Interpretation, the powers of every natural
body must be coordinated in order to achieve the common
good of the universe. Once one has shown that powers are
somehow proportioned and coordinated with one another, then
one can infer they are not merely directed to an effect, but
ordered to it.
However, Feser cannot make use of this kind of argument.
The Final Causality Interpretation aims to show that the mere
fact that a natural body is directed toward its characteristic
effect is sufficient to establish that it is ordered to that effect by
an intelligence, even when the natural body is considered
individually and not in relation to anything external to it. 65
However, when considered individually, many natural bodies
do not appear to exhibit such order. For instance, Aquinas
suggests that the active powers of a fire include heat, lightness,
and dryness.66 Unlike the case of an organism, there is no reason
to believe that these powers must be ordered or coordinated
with each other. In other words, there is no reason to think that
heat is ordered to lightness or dryness, lightness is ordered to
heat or dryness, and so on. However, if this is the case, then
there is no reason to think that the directedness of an active
power is a true ordering. Thus, neither the text cited by Feser
nor Aquinas’s broader commitments on the nature of order
support the view that merely “pointing to” an effect entails
being ordered to it, and the second gloss on Feser’s argument
also fails to establish that Aquinas holds that an intellect is
required to explain the fact that natural bodies incline toward
their characteristic effects.67
65

Feser, “Between Aristotle and William Paley,” 736.
STh I, q. 6, a. 3.
67
To be clear, in rejecting the Final Causality Interpretation’s claim that the mere
directedness of powers constitutes an ordering, I am not thereby rejecting the claim that
Aquinas thinks that powers are ordered to ends. As I have already argued, Aquinas
clearly holds that powers are ordered toward ends. My claim is merely that, in contrast
66

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JOEL JOHNSON

If our reasoning until now is sound, then defenders of the
Final Causality Interpretation have failed to show that their
reading of the second premise reflects a view accepted by
Aquinas. The Fifth Way aims to prove the existence of God by
first observing some feature of reality and then arguing that this
feature can only be explained by a divine intelligence. According to defenders of the Final Causality Interpretation, the
feature that requires explanation is that natural bodies “point
to” determinate effects. But, by their own admission, Aquinas
holds that this feature of reality is explained by something other
than a divine intellect; it is explained by the natures of the
natural bodies. Moreover, each of their attempts to show that
Aquinas thinks that, in addition to the natures of natural bodies,
God is necessary to explain the fact that natural bodies “point
to” determinate effects either contradicts or is deeply in tension
with Aquinas’s clearly stated views. The Final Causality Interpretation thus fails to meet the Quia Demonstration Condition,
and we must look elsewhere for a compelling interpretation of
the Fifth Way.68
III. A FOURTH INTERPRETATION
The three interpretations of the Fifth Way that we have
considered thus far each face difficulties. The Intrinsic Finality
Interpretation and the Extrinsic Finality Interpretation encounto the other interpretations discussed in this paper, the Final Causality Interpretation
does not give an adequate account of this ordering.
68
An additional reason for thinking that merely “pointing to” an effect does not
require intellectual cognition is the fact that so many metaphysicians, from Aristotle to
contemporary powers theorists, have failed to recognize this requirement. Rather, many
of these thinkers take directedness to be a primitive feature of powers themselves, one
that does not require explanation in terms of something else. For convincing accounts of
the role that a divine intelligence plays in Aristotle’s natural philosophy, see Monte
Ransome Johnson, Aristotle on Teleology (Oxford: Oxford University Press, 2005), 25863; and Mariska Leunissen, “Teleology in Aristotle,” in Teleology: A History, ed. Jeffrey
K. McDonough (New York: Oxford University Press, 2020), 39-63. Both argue that
Aristotle’s account of finality does not include reference to a divine ordering intellect,
and none of the passages cited by defenders of the Final Causality Interpretation suggest
that Aquinas holds otherwise.

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73

ter problems on a textual level, while the Final Causality
Interpretation, in addition to lacking textual support for its
reading of the second premise, is unable to meet the Quia
Demonstration Condition. In this section, I advance a fourth
interpretation of the Fifth Way, one that aims to address the
problems encountered by these other interpretations.
This fourth interpretation rests on two observations. The
first observation is that for Aquinas there are at least two
distinct ways in which natural bodies exhibit end-directedness.
He distinguishes between these two kinds of end-directedness in
a passage in De veritate, where he states:
In the case of natural things, there are three prerequisites for obtaining any
end: a nature proportioned to that end, an inclination for the end, which is a
natural desire for the end, and a movement toward the end.69

To possess a nature proportioned to an end just is to be a bearer
of a substantial form; to possess an inclination toward an end
just is to possess active powers that are intrinsically directed
toward an action the terminus of which is an end; and to move
toward an end is to actualize, or exercise, these powers. Thus,
on one hand, Aquinas holds that there is the end-directedness of
a natural body’s inclination toward an end, or more generally, a
natural body’s powers, both active and passive. On the other
hand, Aquinas holds that there is the end-directedness of a
natural body’s action or movement toward an end. These two
features of reality must be distinct on Aquinas’s account because
he allows that a being can possess powers directed toward an
end and yet not move toward the end because it is prevented or
impeded from doing so. 70 A stone may be inclined to move
downwards, but be impeded from actually moving downwards
by the man who is holding it. Likewise, suppose that God
created a world that contained only one being: a fire. In this
69
De Verit., q. 27, a. 2: “Cum enim diversarum naturarum diversi sint fines, ad
consecutionem alicuius finis in rebus naturalibus tria praeexiguntur: scilicet natura
proportionata ad finem illum; et inclinatio ad finem illum, quae est naturalis appetitus
finis; et motus in finem” (Leonine ed., 22/3:794). See also De Pot., q. 5, a. 5.
70
V Metaphys., lect. 6 (Marietti ed., n. 829).

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world, the fire would exist, at least for a short while, and it
would possess an active power inclined toward heating, but it
would never in fact heat anything, because there would be no
other beings present that it could heat. Similar considerations
obtain in the case of passive powers, as a being’s possession of a
passive power is no guarantee that the power will ever be
exercised. In each of these cases, a being is directed to an end in
one sense, it possesses powers intrinsically directed toward an
end, but it is not directed to an end in another sense, it is not
acting for or operating for the sake of the end. For the sake of
clarity, in what follows I will (somewhat arbitrarily) refer to the
intrinsic directedness of active powers using the terms “inclination,” “is inclined,” and “inclines”; the intrinsic directedness of
passive powers using the terms “disposition” and “is disposed”;
and the directedness of actions and activities using the terms
“moves toward,” “acts for,” “operates for,” and “tends toward.”
The second observation follows immediately upon the first:
That a natural body inclines toward an end or is disposed to be
moved toward an end can be explained by its own nature, but
that a natural body acts for an end and through its action attains
the end cannot be. To understand why this is so, we need to
develop Aquinas’s account of action further than we did
earlier. 71 To begin, Aquinas holds that in ordinary cases of
action, an agent acts on a patient, and the action of the agent
and the movement of the patient both tend toward an end.72
The action of the agent tends toward an end because the agent,
through its action, aims at producing a determinate effect in the
patient; and the movement of the patient tends toward an end
because, due to the action of the agent, the patient is moved
from being the bearer of one form to being the bearer of the
form determined by the agent. Moreover, as we saw earlier, the
agent acts on the patient through the operation of its active
71

For a comprehensive account of Aquinas’s views on efficient causality, see Frost,
Aquinas on Efficient Causation and Causal Powers. For more succinct accounts, see
Michael Rota, “Causation,” in The Oxford Handbook of Thomas Aquinas, ed. Brian
Davies and Eleonore Stump (New York: Oxford University Press, 2010), 104-14;
Brower, “First Principles.”
72
STh I-II, q. 12, a. 1.

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75

powers and the patient is acted upon or moved by the agent
through the operation of its passive powers. The agent and the
patient attain the end only after the powers of both have been
perfectly actualized through the production of the intended
form in the patient. For example, when a fire heats some water,
the action of the fire tends toward producing heat in the water,
and the water, due to the action of the fire, tends toward being
heated. The fire attains its end when it has maximally, in respect
to its active power, produced heat in the water, and the water
attains the end when it has maximally, in respect to its passive
power, had heat produced in it.
Now, while the agent is the primary explanation for the enddirected action, the patient also contributes to the explanation.
The end-directed action is explained by the agent because the
agent acts on the patient in accordance with its intrinsic inclination toward an end. The water is heated by the fire because the
fire possesses an active power directed toward the effect of
producing heat. However, the end-directed action is also
partially explained by the intrinsic disposition of the patient.
The water is heated by the fire because the water has the passive
power to be heated. Thus, a natural body’s intrinsic directedness
toward an end—whether the directedness takes the form of the
inclination of an active power or the disposition of a passive
power—is a necessary but not sufficient condition for its action
for an end and, ultimately, its attainment of the end. To act for
and attain an end, in addition to being directed toward the end,
the natural body must be in contact with some suitable agent or
patient. That is, it must come into contact with something that
possesses the requisite active or passive power.
Of course, there are cases of end-directed activity that
require a more complicated account than the one given here.
For instance, the nutritive actions of a living being involve not
merely a change in the patient—the nutrients—but also involve
a change in the agent—the organism. Nevertheless, a natural
body’s end-directed activity, whether as an agent or a patient,
ultimately involves some being or beings extrinsic to it. For this
reason, for a natural body to act for and attain an end more is
required than that it merely possesses powers that “point to”

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some effect. Rather, the natural body must possess powers that
are appropriately related to specific states of affairs extrinsic to
it. In order to act for an end, a fire’s active powers must be proportioned to some really existing thing outside of itself, in this
case something that possesses the passive powers to be heated.
Likewise, in order to be moved to an end by the fire, the water
must possess passive powers proportioned to the fire’s active
powers. In every case, Aquinas holds that a natural body’s
action for an end requires not only that the natural body possesses powers directed toward an end, but that these powers are
appropriately ordered or proportioned to states of affairs in the
world extrinsic to it.73
With these two observations in hand, we can now turn to the
interpretation of the Fifth Way that I will defend, what I will
call the Attainability Interpretation. This interpretation construes the first premise of the Fifth Way as follows:
Attainability Interpretation: Every natural body acts for an end, where the end
is the determinate effect for which it acts and which it regularly attains.

While in some respects similar to the Final Causality Interpretation, the Attainability Interpretation holds that the observation on which the first premise is based is that natural bodies act
for and regularly attain their ends, not merely that they incline
toward ends. Defenders of the Final Causality Interpretation
appear to assume that if a natural body “points to” an end, then
it must also act for the end; and if it acts for an end, it does so
merely as a result of its “pointing.”74 However, as we have just
seen, this view is not supported by Aquinas’s account of natural
73

In De Virtut., q. 1, a. 10, Aquinas states that natural active powers are
proportioned to the powers of natural patients. Similarly, in ibid., ad 13, he states that
there is an order in passive powers that responds to the order of active powers. See also
ScG III, c. 45; and STh I, q. 77, a. 3, ad 1.
74
Feser claims that the Fifth Way is not concerned with the fact that things move
toward ends, but only that they tend toward ends, where tending toward an end is to be
understood merely in terms of possessing an inclination (see Feser, “Between Aristotle
and William Paley,” 732-33). However, this view is undermined by parallel passages
where Aquinas clearly holds that the “tending toward” in question is a thing’s
movement to an end. See, for instance, ScG III, c. 64.

AQUINAS’S FIFTH WAY

77

action. For natural bodies to act for and attain their ends, their
powers must not merely exist but must also be appropriately
ordered to the world extrinsic to themselves. Once this oversight is corrected, it becomes possible to develop an interpretation of the Fifth Way that preserves the insights of the
Final Causality Interpretation while avoiding its problems.
On the Attainability Interpretation, the Fifth Way is similar
in form to an argument for the existence of God that Aquinas
presents in his early commentary on Lombard’s Sentences,
where he writes:
In some agents the knowledge which determines the action and predetermines
the end is united with the agent, just as a human being predetermines the end
of his action for himself. However, in other agents it is separated, as in those
things which act by nature. For the actions of natural things are not in vain
[frustra], as is proved in Book II of the Physics, but are ordained to certain
ends by the intellect who established nature, so that, as the Philosopher says,
the whole working of nature is, in a certain way, the work of intelligence.75

Here, Aquinas argues for the existence of a divine intelligence
on the basis of the observation that “the actions of natural
things are not in vain.” Elsewhere, he distinguishes between
chance and “the vain” by explaining that a chance event occurs
when an unintended effect is produced, while “the vain” occurs
when an intended effect is not produced.76 Thus, to say that the
actions of natural things are not in vain is to say that they are
not frustrated in the pursuit and attainment of their ends.
Moreover, while the above argument focuses on “the vain” in
the context of the actions of natural bodies, Aquinas holds that,
like actions, powers are not in vain as they, too, are capable of
75

II Sent., d. 25, q. 1, a. 1: “Determinatio autem agentis ad aliquam actionem,
oportet quod sit ab aliqua cognitione praestituente finem illi actioni. Sed cognitio
determinans actionem et praestituens finem, in quibusdam quidem conjuncta est, sicut
homo finem suae actionis sibi praestituit; in quibusdam vero separata est, sicut in his
quae agunt per naturam: rerum enim naturalium actiones non sunt frustra, ut in 2
Physic. probatur, sed ad certos fines ordinatae ab intellectu naturam instituente, ut sic
totum opus naturae sit quodammodo opus intelligentiae, ut philosophus dicit” (Scriptum
super libros Sententiarum magistri Petri Lombardi episcopi Parisiensis, vol. 2, ed. R. P.
Mandonnet [Paris: P. Lethielleux,, 1929], 645).
76
II Phys., lect. 10 (Leonine ed., 2:85, n. 9); STh I, q. 25, a. 2, ad 2.

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JOEL JOHNSON

attaining the ends toward which they are ordered. 77 For
instance, a fire’s natural inclination toward heating other things
is not in vain; it is not frustrated by the world extrinsic to the
fire. Rather, the fire is inclined by its active powers toward
producing an effect that is attainable. And likewise for all other
natural bodies.
To see how a similar line of reasoning is present in the Fifth
Way, we need to consider the text more closely. Aquinas begins
the Fifth Way by referencing the fact that natural bodies act
(operantur) for the sake of ends. He supports this claim by
appealing to the regularity of their actions, arguing that natural
bodies regularly act so as to attain what is best (consequantur id
quod est optimum), which shows that they attain the end
(perveniunt ad finem) not by chance, but intentionally (ex
intentione). Now, on the Final Causality Interpretation, this
section of the argument is taken to be primarily concerned with
ruling out chance as a possible explanation for the actions of
natural bodies. On this view, to say that beings regularly act
intentionally for the sake of ends is simply to say that their
actions are the result, not of chance, but of some natural
inclination. However, Aquinas does not merely claim that
natural bodies act with regularity; he claims that they regularly
attain what is best and attain the end. In other words, Aquinas
is observing that natural bodies, through the operation of their
powers, are able to act for and attain the ends toward which
they are ordered. Or to use slightly different language, Aquinas
claims that neither the actions nor the powers of natural bodies
are in vain. Thus, contrary to what is suggested by the Final
Causality Interpretation, the observation on which the first
premise of the Fifth Way is based is not merely that the actions
of natural bodies are not the result of chance. Rather, the first
premise of the Fifth Way depends on the observation that the
actions of natural bodies and the powers from which they
proceed are neither the result of chance, nor are they in vain.
According to the text of the Fifth Way, the fact that the
powers and actions of natural bodies are not in vain establishes
77

ScG II, c. 16. See also ScG I, c. 43; and ScG III, c. 85.

AQUINAS’S FIFTH WAY

79

that they are the result of some intention. However, the
intention in question cannot be the intrinsic inclination of a
natural body, as the Final Causality Interpretation would have
it. 78 Rather, it must be some intention that is capable of encompassing both the natural body and the world extrinsic to the
natural body and explaining why the powers of natural bodies
are ordered to the extrinsic states of affairs necessary for them
to act for and attain their ends.79 For, as our earlier discussion
showed, there is nothing in the end-directed powers of an
individual natural body that requires that it will ever act for an
end, let alone regularly achieve its end. To use again the
example of fire, if one limits oneself to considering just the
metaphysical constituents of fire, there is nothing in the fire that
necessitates that it will ever actually heat anything, because
there is nothing in the fire that entails that its active powers are
intrinsically directed to things that actually exist. In other
words, there is nothing in the fire that entails the existence of
things with the passive power to be heated. Nor is there
anything in the fire that entails that the fire will ever come into
contact with something with the passive power to be heated.
Nevertheless, in the world as we observe it, fires regularly heat
other things. Moreover, we observe that this is true not just in
the case of fires, but generally speaking natural bodies are
78
Wippel, Metaphysical Thought of Thomas Aquinas, 481; and Feser, “Between
Aristotle and William Paley,” 725-26. While translating ex intentione as “as a result of
some natural inclination” is legitimate, it is not the only legitimate translation. Aquinas
also suggests that when a ruler orders the movements of his subjects, the subjects move
by the intention of the ruler. See STh I-II, q. 12, a. 1. Thus, the coordinated movements
of individuals can also be ex intentione. For this reason, when the Fathers of the English
Dominican Province render ex intentione as “designedly,” they too are translating the
phrase legitimately. Which of these translations is preferable requires taking a stance on
the broader question of how the Fifth Way is to be interpreted.
79
Despite differences in approach and terminology, a similar reading of the second
premise of the Fifth Way appears in James Dominic Rooney, “Evolutionary Biology and
Classical Teleological Arguments for God’s Existence,” The Heythrop Journal 54
(2013): 617-30. The key claim in both readings of the second premise is that a divine
intellect is required to explain, not that natural bodies incline toward ends, but that they
act for ends. However, Rooney’s interpretation appears to differ from mine, in that his
reading of the first premise does not reference Aquinas’s claim that nature does nothing
in vain.

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ordered to the world extrinsic to themselves such that they are
regularly able to attain their ends. We see that hot things
regularly heat, cold things regularly cool, dry things regularly
dry, wet things regularly wet, heavy things regularly fall, and
light things regularly rise. Moreover, among living things we see
that plants, animals, and even human beings are ordered both
intrinsically with respect to their functional parts and extrinsically with respect to their environments such that they are
capable of regularly achieving their ends. 80 Only an intention
that exists apart from each individual natural body can explain
the ordering of these individuals to their ends.
To see this more clearly, it may be helpful to contrast the
end-directed actions of natural bodies with the end-directed
actions of human beings. Consider the case of a student who
takes as her end a career as a lawyer. We might say that such a
student desires, or is inclined toward, this career. However,
merely being inclined toward a career is not sufficient for
attaining the career. Additionally, she must adapt her actions to
that end. She must take the appropriate courses and do
sufficiently well in them, she must apply to law schools, she
must develop the interpersonal skills necessary for work in the
law profession, and she must to do many of these things in a
particular order. If her actions are not adapted and proportioned to her end in this way, she will never succeed in
attaining this end. Now, what role does the student’s intellect
play in adapting and proportioning her actions to her end?
First, her intellect allows her to grasp the end toward which she
must direct her actions and understand it as an end. Second, her
intellect allows her to comprehend the relations between the
end and the means to the end. In short, because she possesses an
intellect, she is aware of states of affairs extrinsic to herself and
80

The Attainability Interpretation, like the Intrinsic Finality Interpretation, holds
that considering the end-directed actions of organisms is relevant to one’s understanding
of the first premise of the Fifth Way. However, whereas the Intrinsic Finality
Interpretation holds that the premise refers only to the end-directed actions of
organisms, the Attainability Interpretation sees the premise as referring to end-directed
action more broadly, of which the end-directed actions of organisms are merely a
special case.

AQUINAS’S FIFTH WAY

81

is capable of ordering her actions in response to these states of
affairs.
Now consider the case of a natural body like a fire. Like the
student, the fire has an intrinsic inclination toward an end
which, by itself, is not sufficient for it either to act for or to
attain its end. However, unlike the student, the fire does not
possess an intellect. Because of this, the fire is neither aware of
its end, nor is it aware of the means to its end. As such, it is
unable to order or adapt its actions to its end. Instead, the fire is
determined to, or inclined toward, a type of end (producing a
determinate quantity of heat in a patient) by means of a type of
action (heating). Nevertheless, despite these limitations, fires
manage both to act for ends and by means of these actions to
attain their ends. Moreover, they do so regularly. They
regularly come into contact with beings that have the capacity
to be heated, and heat them.
Now if fires were the only natural bodies that regularly
attained their ends, one might think that fires were not truly
ordered toward heating. Rather, one might suggest that the
relation between fires and objects with the capacity to be heated
is merely an apparent order, not a real one, and underlying this
apparent order is mere chance. On this view, we just happen to
inhabit a world that includes both fires that are inclined toward
ends and the conditions necessary for fires to act for and attain
their ends. An explanation may be required for both the
existence of fires and the existence of things with the passive
power to be heated, but no further explanation is required for
the relation between these beings. However, if Aquinas is
correct—if nature truly does nothing in vain—then the world
we inhabit is ordered in every respect. Not only are fires
ordered to things outside of themselves, but so too are all other
natural bodies. Not only are fires able to act for and attain their
ends, but every kind of natural body is able to do so. The
ubiquity of this order cries out for an explanation that cannot
be explained away as the result of mere chance. Now, we know
that, in contrast to the student, natural bodies do not possess
intellects of their own. Thus, following Aquinas, we can justifiably conclude that there must be some extrinsic intelligence

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that moves these beings to their ends by creating them with
natures by which they are ordered to these ends.
Consequently, the Attainability Interpretation justifies the
second premise of the Fifth Way by means of the now-familiar
argument that if there exists a real order among things, there
must be some explanation for that order, and that explanation
must be an intellect. More specifically, Aquinas argues that the
kind of ordering that is required for a being to act for and attain
an end involves both an apprehension of the end as an end and
an apprehension of the proportion between means and ends.81
Thus, the Attainability Interpretation meets the Quia Demonstration Condition by drawing attention to the fact that, lacking
intellectual powers, natural bodies by their very natures cannot
apprehend either of these things, and, hence, their natures are
unable to explain why their powers are adapted and proportioned to attaining their ends.
This reading the Fifth Way also helps to illuminate Aquinas’s
analogy of the arrow. Particularly noteworthy is the following
passage from his commentary on Aristotle’s On the Heavens:
All that is in nature is either from God, such as the first natural things, or from
nature as a secondary cause, such as the lower effects. But God does nothing
in vain, because, since he is a being who acts through intelligence, he acts for
an end. Likewise, nature does nothing in vain because it acts as moved by God
as a first mover, just as an arrow is not moved in vain insofar as it is shot by an
archer to some definite thing. Therefore, it follows that nothing in nature is in
vain.82

In this passage, Aquinas uses the analogy of the arrow to illustrate his claim that, because nature is ultimately the work of a
divine intelligence, it follows that nature does nothing in vain.
On the Attainability Interpretation, in the Fifth Way Aquinas
81

De Pot., q. 1, a. 5.
I De Caelo, lect. 8: “Omne quod est in natura, vel est a Deo, sicut primae res
naturales; vel est a natura sicut a secunda causa, puta inferiores effectus. Sed Deus nihil
facit frustra, quia, cum sit agens per intellectum, agit propter finem. Similiter etiam
natura nihil facit frustra, quia agit sicut mota a Deo velut a primo movente; sicut sagitta
non movetur frustra, inquantum emittitur a sagittante ad aliquid certum. Relinquitur
ergo quod nihil in natura sit frustra” (Leonine ed., 3:36, n. 14).
82

AQUINAS’S FIFTH WAY

83

uses the analogy of the archer to illustrate the inverse claim:
Because natural bodies do not act in vain, it follows that they
must be moved to their ends by a divine intelligence. However,
his use of the analogy of the arrow in both passages is complementary. If one were to know that an intelligent archer, that
is, an archer who is competent in ordering an arrow to an end,
is responsible for shooting an arrow toward a target, then one
would be justified in believing that the arrow would strike the
target. Similarly, if one were to see an arrow fly through the air
and strike a target, one would be justified in believing that it
was shot by an intelligent archer, even if the archer remained
unseen. In both texts, an important aspect of the analogy is that
the arrow actually moves toward and strikes the target. In the
passage above, it is only because we know that the archer is
intelligent that we are justified in believing that the arrow he
shoots will strike the target. Similarly, in the Fifth Way, it is
only because the arrow moves toward and strikes the target that
we are justified in believing it was shot by an intelligent archer.
As in the case of the arrow, so too in the case of natural
bodies. Observation of the world reveals that natural bodies act
for and attain their ends, and thus their powers and actions are
not in vain. This suggests that they are ordered to their ends by
an intelligence, one who possesses knowledge of the end, the
means to the end, and the proportion between the means and
the end. Thus, the analogy of the arrow illustrates the claim that
a divine intelligence moves natural bodies to their ends by
creating them with natures that are not only directed toward
ends, but directed toward attainable ends. And being directed
toward attainable ends suggests that the powers of natural
bodies do not merely point to determinate effects, but are
ordered to those effects.
Finally, on the Attainability Interpretation, the argument of
the Fifth Way can be readily extended to establish the existence
of a unique divine intelligence. In question 11, article 3 of the
Summa theologiae, where Aquinas treats the topic of divine
uniqueness, he articulates a line of reasoning that is in some
respects already implicit in the Attainability Interpretation. He
argues that the order and harmony among the many diverse

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beings with divergent ends in the natural world can only be
explained if all natural bodies are directed by a single intellect.83
He often compares God’s government of the universe with a
political ruler’s government of his kingdom. 84 Just as a ruler
orders and directs the activities of his kingdom, so too does
God order and direct the activities of natural bodies. If there
were two or more rulers of a single kingdom, neither of whom
was subordinate to the other, then conflicts would invariably
break out over how the kingdom was to be governed. These
conflicts would manifest themselves as disharmonious relations
among citizens. The same is true, Aquinas thinks, of the natural
world. If there were more than one intellect responsible for
directing natural bodies to their ends, then there would be more
than one order of ends in the universe and these different
orders would conflict with each other. Disharmonious relations
among natural bodies would become apparent. In short, nature
would do something in vain. However, Aquinas thinks that this
is not what we observe in nature. Hence, we can conclude that
there must be only one intellect responsible for directing natural
bodies to their ends.85
CONCLUSION
I want briefly to suggest that if the interpretation that I have
defended in this paper is correct, then the Fifth Way is not
without contemporary relevance, even for those working outside of the Aristotelian tradition. Although contemporary causal
powers theorists often hold positions contrary to Aquinas’s on
83

STh I, q. 11, a. 3.
De Verit., q. 5, a. 2. See also ScG I, c. 42; and STh I, q. 103, a. 6, ad 3.
85
Like the Attainability Interpretation, the argument that the Extrinsic Finality
Interpretation attributes, albeit mistakenly, to the Fifth Way can also be extended to
establish the uniqueness of the divine intellect. However, given that the two
interpretations read the first premise differently, they would also read the analogy
differently. On the Attainability Interpretation, the focus would be on the ruler’s role in
ordering the kingdom such that every citizen is able to achieve his own individual good.
In contrast, on the Extrinsic Finality Interpretation, the analogy would focus on the
ruler’s role in promoting the common good of the kingdom. Although closely related,
these two ways of extending the argument are ultimately distinct.
84

AQUINAS’S FIFTH WAY

85

the nature of powers, nevertheless, many contemporary
accounts of causal powers must confront what Neil Williams
calls the “the problem of fit.” He describes this problem as
follows:
The problem is one that concerns the way those powers work together to
produce their manifestations. Powers must (typically) act in conjunction with
one another to produce manifestations; a requirement of their working
together is that they have the appropriate ‘fit’ for one another. If the salt is to
manifest its solubility in the water, the water must likewise manifest its power
to have the salt go into solution; there is no space for disagreement. However,
as powers are intrinsic, and the manifestations they are capable of producing
are set and incapable of change, their managing to line up is a matter of great
mystery. Somehow the powers must be engineered such that they have the
appropriate fit for one another. I call this the problem of fit.86

If the interpretation that I have defended in this paper is correct, Aquinas’s Fifth Way is a kind of argument for the existence
of God from the problem of fit. More specifically, it is an argument for the existence of God on the basis of the observation
that the powers of natural bodies “fit” the extrinsic world such
that they are able to attain their ends. Though translating the
argument of the Fifth Way into language amenable to contemporary powers theorists is far beyond the scope of this paper, it
nevertheless appears to be an avenue for development.
For those already within the Aristotelian tradition, the
soundness of the argument is even more plausible. The Fifth
Way, taken as it is “from the governance of things,” ultimately
seeks to prove the existence of a divine intellect who orders
nature providentially. This divine intellect’s providential ordering of nature explains why natural bodies are regularly able
to act for and attain those ends toward which they are directed;
it is the guarantor of the Aristotelian dictum that nature does
nothing in vain. In Aquinas’s own words, “among the works of

86

Neil E. Williams, “Puzzling Powers: The Problem of Fit,” in The Metaphysics of
Powers: Their Grounding and Their Manifestations, ed. Anna Marmadora (New York:
Routledge, 2010), 84-105.

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God, none is in vain, just as none is in vain among the works of
nature, for nature has this trait from God.”87

87

ScG III, c. 156. I would like to thank the editors and two anonymous reviewers of
The Thomist for very helpful comments on an earlier draft of this article.

The Thomist 87 (2023): 87-130

THOMAS AQUINAS ON KNOWING THE ESSENCES OF
MATERIAL SUBSTANCES
BENJAMIN M. BLOCK
Thomas Aquinas College
Santa Paula, California

I. THE DIFFICULTY OF ATTAINING
KNOWLEDGE OF ESSENCES OF SUBSTANCES

A

CONDENSED OUTLINE of Thomas Aquinas’s explanation of how we attain intellectual knowledge might
be expressed as follows: the activity of the agent intellect,
using the phantasm as its instrument, produces impressed
intelligible species in the possible intellect, which in turn forms
its own concepts, or expressed intelligible species, through
which it knows the natures of things, in a universal manner.1
Much study would be required before one could even begin to
unpack the carefully thought-out details that have been worked
out in the above description, but in what follows, I wish to
begin by first taking for granted the whole Thomistic epistemological doctrine thus outlined.
Given this explanation, the problem that I here propose to
solve is how it is possible to provide human beings with a
knowledge of the essences of material substances.2 For if it is
1
Cf. ScG I, c. 53 (Marietti ed., 441-44) (Thomas Aquinas, Liber de veritate
catholicae fidei contra errores infidelium seu Summa contra gentiles, ed. P. Marc,
C. Pera, and P. Caramello [Turin and Rome: Marietti, 1961]). Parenthetical numbers in
citations of Marietti editions of Thomas’s works refer to paragraph numbers in those
editions.
2
The term “essence” signifies what a thing is—it is that “through which and in
which a being has existence” (“per eam et in ea ens habet esse”) (De Ente, c. 1 [Leonine
ed., 43:370, ll. 51-52). Thomas notes that “essence is properly and truly in substances,

87

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BENJAMIN M. BLOCK

true that all human knowledge has its origin in the senses3 and
that the senses provide likenesses only of accidents,4 then it is
unclear how the agency of the intellect, together with the
agency of the phantasms, would be at all sufficient to produce
any likeness of a material substance’s essence, for the production of the likeness of a substance’s essence from the likeness
of mere accidents seems to be producing something from
nothing.5 And yet, Thomas clearly states that the proper object
but in accidents in a certain way and secundum quid” (“essentia proprie et vere est in
substantiis, sed in accidentibus est quodammodo et secundum quid”) (ibid. [Leonine ed.,
43:370, ll. 55-57]). As for the term “substance,” some substances (immaterial
substances) are completely determined by their essence, whereas material substances
exist only when their form is further received in and limited by a particular matter;
hence, what these material substances are (i.e., their essence) must include both form
and matter (see De Ente, c. 4 [Leonine ed., 43:376, ll. 62-64]).
All citations of the Leonine edition of Aquinas’s works (Sancti Thomae Aquinatis
doctoris angelici Opera omnia iussu Leonis XIII P.M. edita [Rome: Ex Typographia
Polyglotta S.C. de Propaganda Fide, 1882–]) will include volume, page, and line
numbers. All translations of Thomas are my own.
3
“According to the Philosopher, all our knowledge has its beginning from the sense”
(“Secundum philosophum omnis nostra cognitio a sensu ortum habet”) (Super Boet. De
Trin., q. 1, a. 3, s.c. [Leonine ed., 50:86, ll. 59-60]).
4
“Our intellect, which properly knows the quiddity of a thing as its proper object,
receives from the sense[s], whose proper objects are external accidents” (“Intellectus
noster, qui proprie est cognoscitivus quidditatis rei ut proprii obiecti, accipit a sensu,
cuius propria obiecta sunt accidentia exteriora”) (STh I, q. 18, a. 2 [Leonine ed.,
4:226]). “For to understand [intelligere] is as if to read inside a thing [intus legere]; for
sense and imagination know only external accidents, but the intellect alone reaches to
the interior and essence of a thing” (“Enim intelligere quasi intus legere. Sensus enim et
imaginatio sola accidentia exteriora cognoscunt; solus autem intellectus ad interiora et
essentiam rei pertingit”) (De Verit., q. 1, a. 12 [Leonine ed., 22/1:35, ll. 26-29]). Cf. De
Verit., q. 10, a. 6 (Leonine ed., 22/2:311-13); III De Anima, c. 7 (Leonine ed., 45/1:236,
ll. 62-85); STh I, q. 84, a. 7 (Leonine ed., 5:325); STh I, q. 84, a. 6 (Leonine ed.,
5:323-24); STh I, q. 89, a. 1 (Leonine ed., 5:370-71); etc. See also: John Wippel, The
Metaphysical Thought of Thomas Aquinas: From Finite Being to Uncreated Being
(Washington, D.C.: The Catholic University of America Press, 2000), 35 n. 43.
5
I am by no means the first to note the apparent difficulty here. See, for example,
the overview of this problem presented by Ralph B. Gering, in “The Knowledge of
Material Essences according to St. Thomas Aquinas,” The Modern Schoolman 33
(1956): 153-81. See also: Norman Kretzmann, “Infallibility, Error, and Ignorance,”
Canadian Journal of Philosophy, suppl. vol. 17 (1991), 159-94; John Jenkins, “Aquinas
on the Veracity of the Intellect,” Journal of Philosophy 88 (1998): 623-32; and

KNOWING THE ESSENCES OF MATERIAL SUBSTANCES

89

of the human intellect is the quiddity (or essence) of a material
thing, and he further maintains that our intellect cannot fail in
its understanding of this object.6
Before attempting to resolve this problem, I want to emphasize its importance briefly, lest unavoidably technical details
fool us into thinking of this problem as merely an esoteric
exercise in understanding medieval terminology. The question
of how we know the essences of material beings lies at the heart
of all our questions about what we can know in this life and
thus touches directly on questions of man’s purpose and final
end.7 When I see, touch, or otherwise experience something—
especially, P. L. Reynolds, “Properties, Causality and Epistemological Optimism in
Thomas Aquinas,” Recherches de théologie et philosophie médiévales 68 (2001):
270-309.
6
“But the proper object of the human intellect, which is joined to the body, is the
quiddity or nature existing in bodily matter” (“Intellectus autem humani, qui est
coniunctus corpori, proprium obiectum est quidditas sive natura in materia corporali
existens”) (STh I, q. 84, a. 7 [Leonine ed., 5:325]); “The intellect is not deceived about
the what it is”) (“Intellectus non decipitur in quod quid est”) (III De Anima, c. 5
[Leonine ed., 45/1:224, ll. 12-13).
7
Aristotle writes, “None of the other animals is happy, since they in no way share in
contemplation. Happiness extends, then, just so far as contemplation does, and those to
whom contemplation more fully belongs are more truly happy, not accidentally, but in
virtue of the contemplation; for this is in itself precious” (Aristotle, Nic. Ethic.
10.8.1178b27-31 [The Complete Works of Aristotle, ed. Jonathan Barnes, vol. 2
(Princeton, N.J.: Princeton University Press, 1984), 1863]). Thomas himself, in his own
Christian way, recognizes the truth of this statement: “But [the study of wisdom] is
more sublime because chiefly through it man approaches the divine likeness, which
makes everything in wisdom. Hence, because likeness is the cause of delight, the study
of wisdom chiefly joins one to God through friendship” (“Sublimius autem est quia per
ipsum homo praecipue ad divinam similitudinem accedit, quae omnia in sapientia fecit:
unde, quia similitudo causa est dilectionis, sapientiae studium praecipue Deo per
amicitiam coniungit”) (ScG I, c. 2 [Marietti ed., 8]). This love of contemplation is why,
as Robert Brennan once explained, “There is scarcely a page in all [Thomas’s] vast
tomes that does not contain some reference to his views on knowledge and its
processes” (Robert Edward Brennan, O.P., Thomistic Psychology: A Philosophic Analysis
of the Nature of Man [New York: The Macmillan Company, 1941], 173). Here we
should of course distinguish between natural and supernatural contemplation—though
this article is not the place to work out these distinctions. I will simply note that I am in
complete agreement with Maritain here that “metaphysics is not the doorway to
mystical contemplation. That doorway is Christ’s humanity, for by Him we have been
given grace and truth” (Jacques Maritain, Distinguish to Unite or The Degrees of

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for example, a dog, a plant, a rock, the moon, another human
person—how is it that I can claim that I really know anything
else besides my own ideas and my own conscious activities?
Perhaps indeed it might seem more reasonable to say, together
with John Locke and other so-called empiricists, “Since the
mind, in all its thoughts and reasonings, has no other immediate
object but its own ideas, which it alone does or can contemplate, it is evident, that our knowledge is only conversant
about them.”8 We should here remember that Locke, like
Aristotle and like Thomas, also claims that all our knowledge
originates from our senses. It is precisely in how Locke and
other empiricists understand this process of knowing to take
place that leads them to fundamental and far-reaching disagreements with the long-held tradition of perennial philosophy.9

Knowledge, trans. Gerald B. Phelan, The Collected Works of Jacques Maritain, vol. 7
[Notre Dame, Ind.: University of Notre Dame Press, 1995], 13).
8
John Locke, An Essay Concerning Human Understanding, ed. Kenneth P. Winkler
(Indianapolis: Hackett Publishing Company, Inc., 1996), bk. 4, chap. 1, §1.
9
Note that Locke himself contends that his epistemology at least does not prevent an
indirect knowledge of things: “Simple ideas are not fictions of our fancies, but the
natural and regular productions of things without us, really operating upon us; and so
carry with them all the conformity which is intended; or which our state requires: for
they represent to us things under those appearances which they are fitted to produce in
us” (ibid., bk. 4, chap. 4, §4]). Yet there is a clear and logical progression from the
principles of Locke through Hume and to Kant, who ends up concluding that there
simply cannot be any knowledge of things in themselves, period: “Since that which is
not appearance cannot be an object of experience, it can never overstep the limits of
sensibility, within which alone objects are given to us” (Immanuel Kant, Critique of Pure
Reason, trans. Paul Guyer and Allen Wood [New York: Cambridge University Press,
1998], A246/B303); “How they might be outside of the relation to possible experience
and consequently to sense in general . . . will always remain unknown to us, so that it
even remains unknown whether such a transcendental (extraordinary) cognition is
possible at all” (ibid., A258/B314). As Aristotle might note here: “The least initial
deviation from the truth is multiplied later a thousandfold. . . . A principle is great
rather in power than in extent; hence that which was small at the start turns out a giant
at the end” (Aristotle, De Caelo 1.5.271b8-9, b12-13 [Barnes, ed., 2:452]). “As they
begin badly, [they] cannot fail to end badly” (Aristotle, Polit. 5.1.1302a6-7 [Barnes, ed.,
2:2067]); “The beginning is thought to be more than half of the whole” (Aristotle, Nic.
Ethic. 1.7.1098b7 [Barnes, ed., 2:1736]).

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In contrast, Thomas Aquinas thinks that we really can attain
actual knowledge of things, not just of our own ideas, and
things are knowable only in their natures or essences.10
Following Aristotle, Thomas further thinks that it is manifest by
experience that what we know first, prior to our ideas, is
precisely this “external,” material world, and it is this very fact
that must be explained by our epistemology; in typical
Aristotelian fashion, Thomas does not wish to explain away
what is more manifest by what is less manifest.11 But merely
positing our knowledge of things as a starting point by no
means removes the question of how this knowledge is possible,
and because the difficulties involved in understanding this
question are indeed great and intricate—especially for those
who, like Thomas, hold that all knowledge originates in the
senses—the temptation to turn away from a natural realism
remains an ever-looming danger. All the more so then, the
question of how Thomas thinks it is possible to know the
essences of material substances is worth pursuing. Despite the
fact that this article will necessarily be limited to trying to
understand just one piece of Thomas’s epistemology and cannot
demonstrate anything beyond that limited scope, what is
ultimately at stake is precisely the question of what knowledge,
if any, is possible to us in this life; and, in the words of Joseph
Pieper: “True philosophy rests upon the belief that the real
wealth of man lies not in the satisfaction of his necessities, nor,

10
“A thing is knowable through its essence” (“Res per essentiam suam cognoscibilis
est”) (II Sent., d. 37, q. 1, a. 1 [Scriptum super libros Sententiarum magistri Petri
Lombardi, 4 vols., 1-2 ed. Pierre Mandonnet, 3-4 ed. Maria Fabianus Moos (Paris:
Lethielleux, 1929-47), 2:944]).
11
See, for example, the kind of arguments Thomas presents in De unitate intellectus:
“But if the intelligible species of the possible intellect are neither received from phantasms nor illuminate them, they will be altogether different and have nothing proportional to them, nor would the phantasms cause anything to be understood, which is
manifestly false” (“Si autem species intelligibiles intellectus possibilis neque accipiuntur a
phantasmatibus, neque irradiant super ea, erunt omnino disparatae et nihil proportionales habentes, nec phantasmata aliquid facient ad intelligendum; quod manifeste
repugnat”) (De Unit. Intel., c. 4 [Leonine ed., 43:310, ll. 257-62]).

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again, in ‘becoming lords and masters of nature,’ but rather in
being able to understand what is—the whole of what is.”12
II. A PROPOSED THOMISTIC SOLUTION:
KNOWLEDGE OF SPECIFIC ESSENCES OF SUBSTANCES
For Thomas, intellectual knowledge does not begin with the
knowledge of any specific kind of substance; rather, it begins
with the knowledge of being,13 which is then distinguished into
at least an implicit knowledge of being as substance and being as
accidents (i.e., being that properly exists only in substances). It
should be stressed that this knowledge of being and the
12
Josef Pieper, “The Philosophical Act,” in Leisure the Basis of Culture; The
Philosophical Act, trans. Alexander Dru [San Francisco: Ignatius Press, 2009], 92.
“When man shuts himself up in his environment, in the sphere defined and limited by
his immediate needs, the degeneration that follows is only possible because spiritual
degeneration is possible. The really human thing is to see the stars above the roof, to
preserve our apprehension of the universality of things in the midst of the habits of daily
life, and to see ‘the world’ above and beyond our immediate environment. And with
that we are back unawares at our first question: ‘What do we mean by philosophizing?’
It means to experience the fact that our immediate surroundings, prescribed as they are
by the aims and needs of life, not only can be, but must be broken in upon (not only
once but ever and again), by the disturbing call of ‘the world’, of the whole world and
the everlasting and essential images of things mirrored by reality” (ibid., 105).
13
“That which the intellect conceives first, as the most known and that into which
all conceptions resolve, is being” (“Illud autem quod primo intellectus concipit quasi
notissimum et in quod conceptiones omnes resolvit est ens”) (De Verit., q. 1, a. 1
[Leonine ed., 22/1:5, ll. 100-102]). “Being (ens) is the first [thing] that falls under
apprehension, simply speaking” (“Ens est primum quod cadit in apprehensione
simpliciter”) (STh I-II, q. 94, a. 2 [Leonine ed., 7:170]). “But it must be said that what
are more universal are what is known first by simple apprehension, for being [ens] falls
first in the intellect, as Avicenna says, and animal falls in the intellect before human. For
just as in real being [esse naturae], which proceeds from potency into act, an animal is
prior to a human, so too in the generation of knowledge, animal is conceived in the
intellect prior to human” (“Sed dicendum, quod magis universalia secundum simplicem
apprehensionem sunt primo nota, nam primo in intellectu cadit ens, ut Avicenna dicit, et
prius in intellectu cadit animal quam homo. Sicut enim in esse naturae quod de potentia
in actum procedit prius est animal quam homo, ita in generatione scientiae prius in
intellectu concipitur animal quam homo”) (I Metaphys., lect. 2 [In duodecim libros
Metaphysicorum Aristotelis expositio, ed. M.-R. Cathala and Raymond M. Spiazzi, 2nd
ed. (Turin and Rome: Marietti, 1971), 46]).

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93

distinction between substance and accident will undoubtedly be
only vague and implicit, at least initially. But any child who
distinguishes between, for example, her mother and her
mother’s color or shape can do so only after first achieving
some implicit understanding that some things exist in themselves and some things exist in what exists in itself.
The question of how this prior, general knowledge of being
and substance can happen will be addressed in the section that
follows; in this section, however, I wish first to explain how,
according to Thomas, the knowledge of a specific kind of
essence (e.g., the essence of a man, of a horse, of a tree, etc.)
can come about. In the Summa contra gentiles, after Thomas
explains that “whatever the intellect knows about anything, it
knows through the knowledge of the substance of that thing,”
he immediately adds that the intellect “must arrive at its
understanding of the substance through the knowledge of
sensible accidents.”14 It follows then that, whereas the general
14
“Quicquid intellectus de aliqua re cognoscit, cognoscit per cognitionem substantiae
illius rei. . . . per sensibilium accidentium cognitionem oportet ad substantiae
intellectum pervenire” (ScG III, c. 56 [Marietti ed., 2328]). “Because substance exists in
a distinguished and primordial way, any term expressing a subject of existence or an
object of understanding involves some sort of relation, no matter how indirect, to what
is both the primary subject of existence and the primary object of understanding,
namely, substance” (Yves Simon, “Essay on Sensation,” in Philosopher at Work: Essays
by Yves Simon, ed. Anthony O. Simon [Lanham, Md.: Rowman and Littlefield, 1999],
99). “In its first act, the intellect does not receive a perfect likeness of the quiddity,
which would represent this essence in all its complexity. Although certain texts could let
it be thought that such is the position of Thomas, a number of other texts attest that
quidditative knowledge is not immediate and requires the work of reason and the use of
certain accidental properties. Nevertheless, for logical reasons, it is necessary to posit a
knowledge of the essence that precedes the intellectual knowledge of a singular that has
this essence. This is precisely the advantage of the notion of substance: it has essential
properties prior to all essential predication. Socrates is necessarily a human being before
he is white. In the order of knowing, one finds, in a different way, this priority of
substantial and universal knowledge, which corresponds to the primacy of the form in
the quiddity. It is first by its substantial form that a being belongs to this or that natural
species. One first knows an individual as belonging to a natural species, whether or not
one considers the true form of the individual or is mistaken. It is logically necessary to
form a universal substantial concept in the first place” (“L’intellect ne reçoit pas une
similitude parfaite de la quiddité dès son premier acte, qui lui représenterait cette
essence dans toute sa complexité. Même si certains textes peuvent laisser penser que

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knowledge of being is conveyed to the intellect immediately in
the first intellectual apprehension, and furthermore, the general
knowledge of substance (being-existing-in-itself) must soon
follow, it remains that the knowledge of a specific kind of
substance can be obtained only posteriorly through the knowledge of its accidents. This interpretation allows us to save both
of the principles that Thomas here lays out, even in the same
passage, namely, (1) that the intellect knows everything through
its initial general knowledge of being and substance and (2) that
the intellect knows the specific essences of substances through
knowledge of those substances’ accidents.
Before delving into this doctrine in more detail, we should
note that neither of these principles is a later development in
Thomas’s thought; they are both consistently present throughout his writings. In his early Sentences commentary, after
arguing that the quiddity of things is the proper object of the
intellect, Thomas shows that the knowledge of a specific kind of
substance is still attained only through knowledge of a thing’s
accidents. First Thomas argues that the intellect really attains to
a thing’s essence:
“Intellect” by its own name signifies a knowledge that extends to what is
internal in a thing. Hence, since the sense and imagination are concerned with
the accidents that are, as it were, standing around the essence of a thing, the

telle est la position de Thomas, de nombreux autres attestent que la connaissance
quidditative n’est pas immédiate, qu’elle requiert un travail de la raison et l’usage de
certaines propriétés accidentelles. Néanmoins, pour des raisons logiques, il faut poser
une connaissance de l’essence qui précède la connaissance intellectuelle d’un singulier
ayant cette essence. C’est précisément l’intérêt de la notion de substance. Celle-ci
possède des propriétés essentielles antérieures à toute prédication essentielle. Socrate est
nécessairement un homme avant d’être blanc. Dans l’ordre cognitif, on retrouve, sous
une autre forme, cette priorité de la connaissance substantielle et universelle, qui
correspond au primat de la forme dans la quiddité. C’est d’abord par sa forme
substantielle qu’un étant appartient à telle ou telle espèce naturelle. On connaît d’abord
un individu en tant qu’il appartient à une espèce naturelle, que l’on considère ou non la
véritable forme de l’individu ou que l’on se trompe. Il est logiquement nécessaire de se
former en premier lieu un concept substantiel universel”) (Robert Aurelian, “Penser la
substance: Étude d’une question médiévale (XIIIe-XIVe siècles)” [PhD. diss., Université
de Nantes, 2005], 128); translation mine.

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intellect extends to its essence. Hence according to the Philosopher, the object
of the intellect is the what [quid].15

But he immediately follows this claim with an explanation of
how this is possible, noting that there is something special about
the manner in which human intellects apprehend a specific
essence:
But in the apprehension of this essence there is a difference. . . . Sometimes an
intellect does not arrive at what is internal except through those things that are
set around it, as if through certain gates; and here is the mode of apprehension in men, who from effects and properties proceed to the knowledge of
the essence of a thing. And because in this there must be a certain discourse,
therefore the apprehension of man is called reason, although reason is completed in understanding because inquiry leads to the essence of a thing. Hence,
if there is anything that is immediately apprehended without the discourse of
reason, there is not said to be reason of these things, but understanding, as, for
example, first principles, which when heard, everyone immediately accepts. . .
. But as the human mind does not advance to the essence of the thing except
through accidents, so too neither does it advance to spiritual things except
through bodily things and likenesses of sensible things.16

This beautiful passage from the Sentences commentary
demonstrates that, even early in his career, Thomas did not
think that the human intellect has direct and immediate
knowledge of specific kinds of essences (except, of course, in
the general sense already outlined above), despite the fact that
15

“Intellectus secundum suum nomen importat cognitionem pertingentem ad intima
rei. Unde cum sensus et imaginatio circa accidentia occupentur quae quasi circumstant
essentiam rei, intellectus ad essentiam ipsam pertinget. Unde, secundum Philosophum . .
. objectum intellectus est quid” (III Sent., d. 35, q. 2, a. 3, qcla. 1 [Moos, ed., 3:1198]).
16
“Sed in apprehensione hujus essentiae est differentia. . . . Aliquando vero ad intima
non pervenitur nisi per circumposita quasi per quaedam ostia; et hic est modus
apprehendendi in hominibus, qui ex effectibus et proprietatibus procedunt ad
cognitionem essentiae rei. Et quia in hoc oportet esse quemdam discursum, ideo hominis
apprehensio ratio dicitur, quamvis ad intellectum terminetur in hoc quod inquisitio ad
essentiam rei perducit. Unde si aliqua sunt quae statim sine discursu rationis
apprehendantur, horum non dicitur esse ratio, sed intellectus; sicut principia prima,
quae quisque statim probat audita. . . . Sicut autem mens humana in essentiam rei non
ingreditur nisi per accidentia, ita etiam in spiritualia non ingreditur nisi per corporalia,
et sensibilium similitudines” (III Sent., d. 35, q. 2, a. 2, qcla. 1 [Moos, ed.,
3:1198]); emphases added.

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essences or quiddities are indeed the proper object of the
intellect. Since this seems to be a consistent teaching of Thomas,
all the passages in which he talks about essences as the proper
object of the intellect ought not to be interpreted in such a way
as to imply that he believes there is any sort of direct access to
the knowledge of specific kinds of essences of substances.17
In the above passage, Thomas also provides a helpful
analogy: just as the human intellect arrives at a knowledge of
spiritual things through bodily things (i.e., through reasoning
from them a posteriori, from effect to cause), so too does the
human intellect arrive at knowledge of the essences of specific
kinds of substances through a knowledge of their accidents (i.e.,
by reasoning from effect to cause). As he explains more
explicitly in De ente: “For essential differences are unknown in
sensible things also, and hence they are signified through
accidental differences, which arise from essential differences, as
a cause is signified through its effect.”18 As we will see below,
this cause-and-effect relationship between the essence and its
accidents is in fact the key to understanding how the knowledge
of accidents can provide any knowledge of the essence at all.

17
“It is licit to say that . . . substantial essences are to some degree ‘discovered’ by
the mind, neither ‘bared’ certainly, nor from within . . . but discovered by their outsides
(the accidents, in turn, not being known by the inside, which would be to know them in
derivation from the substance, but by the operations)” (Maritain, Degrees of Knowledge,
220).
18
“In rebus enim sensibilibus etiam ipse differentie essentiales ignote sunt; unde
significantur per differentias accidentales que ex essentialibus oriuntur, sicut causa
significatur per suum effectum” (De Ente, c. 5, §94 [Leonine ed., 43:379, ll. 76-80];
emphasis added). “Because the essential principles of things are unknown to us, we must
therefore use accidental differences in signifying essential things. . . . And through these,
namely, through accidental differences, we arrive at knowledge of essential things”
(“Quia principia essencialia rerum sunt nobis ignota, ideo oportet quod utamur
differnciis accidentalibus in designatione essencialium. . . . Et ut per ea, scilicet per
differencias accidentales, perueniamus in cognitionem essencialium”) (I De Anima, c. 1
[Leonine ed., 45/1:7, ll. 254-60]). “Essential forms are not per se known by us but must
be manifested through some accidents that are signs of that form” (“Forme essenciales
non sunt nobis per se note, oportet quod manifestentur per aliqua accidencia, que sunt
signa illius forme”) (II Post Anal., lect. 13 [Leonine ed., 1*2:222, ll. 119-21]).

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However, there is an additional epistemological problem
here that must first be acknowledged. Whenever one has
knowledge of something that is strictly accidental to the
knowledge of something else, the knowledge of the former can
never provide any necessary or essential knowledge of the other
thing. Thomas himself affirms this logical principle: “Those
things that we know to exist through something accidental to
them are such that in no way through this knowledge do we
know what they are, because we do not even truly know that
they exist through an accident of this kind.”19 If the only
knowledge available to us regarding substances were accidental,
then no knowledge of substances would be essential. If I know
only the accidents of a thing and not the thing itself in any way,
I cannot even say whether those accidents are caused by one
thing or by many things.
For example, say I notice perturbations in the orbit of a
planet. I may posit that there is another planet causing those
perturbations, but in fact, there could be many objects causing
them all at once, or indeed, several successive and different
objects causing those perturbations at different times. In this
example, knowledge of these accidents (the perturbations) alone
would reveal nothing necessary about even the existence of any
particular substance (though one should note that even in this
example, some substance must exist if there are accidents).20 But
if it is true that the accidental cannot provide knowledge of the
substantial, then we are back at square one: How can the
knowledge of sensible accidents produce knowledge of the
essences of substances at all?
Part of the answer to this quandary lies in the ambiguity of
the word “accident.” For even though a being is either a
substance or an accident (and nothing in between), one can still
make a distinction between those accidents that are predicated
of a subject “accidentally” and those accidents that are
19
“Illa de quibus scimus quod sunt per aliquod accidens ipsorum, nullo modo per
hoc se habent ad hoc quod cognoscamus de ipsis ‘quid est’, quia neque etiam per
huiusmodi accidens uere scimus ea esse” (II Post Anal., lect. 7 [Leonine ed., 1*2:199,
ll. 156-60]).
20
Cf. II Post Anal., lect. 19 (Leonine ed., 1*2:239-41).

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BENJAMIN M. BLOCK

predicated of a subject as its “properties.”21 “Properties” are
those accidents that are not wholly accidental to a thing’s
essence but instead are caused by it, even though these accidents
are neither the essence itself nor a part of that essence.22 We
should note that the term “property” is used in a number of
analogous and related senses,23 but for the purposes of
21

“If we take ‘accident’ in this way [i.e., as one of the five predicables in logic, rather
than as the exclusive distinction between substance and accident], then there is
something intermediate between substance and accident, that is, between a substantial
predicate and an accidental predicate; and this is a property. For it is indeed like a
substantial predicate inasmuch as it is caused from the essential principles of the species;
and therefore, the property of the subject is demonstrated through the definition, which
signifies the essence. But it is like an accidental predicate in that it is neither the essence
of the thing nor a part of the essence, but something besides it” (“Sic igitur accipiendo
accidens est aliquid medium inter substantiam et accidens, id est inter substantiale
predicatum et accidentale: et hoc est proprium. Quod quidem conuenit cum substantiali
predicato in quantum causatur ex principiis essentialibus specie: et ideo per
diffinitionem significantem essentiam demonstratur proprietas de subiecto. Cum
accidentali uero predicato conuenit in hoc quod nec est essentia rei nec pars essentie, set
aliquid preter ipsam”) (De Spirit. Creat., a. 11 [Leonine ed., 24/2:120, ll. 272-81];
emphasis added).
22
“The actuality of the accidental form is caused by the actuality of the subject. Thus
that subject, inasmuch as it is in potency, is receptive of the accidental form, but
inasmuch as it is in act, it is productive of it. But this I say about the proper and per se
accident” (“Actualitas formae accidentalis causatur ab actualitate subiecti. Ita quod
subiectum, inquantum est in potentia, est susceptivum formae accidentalis: inquantum
autem est in actu, est eius productivum. Et hoc dico de proprio et per se accidente”)
(STh I, q. 77, a. 6 [Leonine ed., 5:246]). “Since the existence of an accident depends on
the subject, it must also be the case that its definition, signifying its existence, contains
the subject in itself. Hence, when a subject is put in the definition of a predicate that is
its proper accident, this is the second mode of per se” (“Cum esse accidentis dependeat a
subiecto, oportet etiam quod diffinitio eius significans esse ipsius contineat in se
subiectum. Vnde secundus modus dicendi per se est quando subiectum ponitur in
diffinitione predicati quod est proprium accidens eius”) (I Post Anal., lect. 10 [Leonine
ed., 1*2:39, ll. 61-67]); emphasis added).
23
“In the sense intended here—for the word has several meanings—a proprium is a
non-essential attribute that is convertible (coextensive) with its subject qua species. The
standard medieval examples of properties (also known in the schools as ‘proper
accidents’ and ‘proper passions’) are the capacity to laugh in human beings and
containing the sum of two right angles . . . in triangles. . . . The term proprium has other
senses too, and its precise sense is not always clear. In what is perhaps the most basic
sense of the term, a proprium is anything that belongs to one thing alone (whether or

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99

understanding the attainment of the knowledge of the essences
of material substances, we are particularly interested in those
proper accidents that flow from the essence necessarily and thus
always exist with that essence, even though they are not
identical with the essence itself: “For if any accident exists in a
subject always and out of necessity, it must be because it has a
cause in the subject; once the subject is supposed, it is impossible for the accident not to exist.”24 It is precisely these sorts
of proper accidents that allow for the knowledge of substances
through their accidents, for, as Thomas notes, “Substantial
forms are unknown through themselves, but they become
known to us through their proper accidents.”25 And again, in De
veritate: “The substantial differences of things are unknown to
not that thing always possesses it)” (Reynolds, “Properties, Causality and
Epistemological Optimism in Thomas Aquinas,” 272-73). Reynolds then points out a
further possible distinction: “It seems that terms such as proprium and passio propria
sometimes denote accidental features that belong necessarily and naturally to a species
but not exclusively so” (ibid., 274). In the strictest sense of the term, however, a
property is that which belongs to only one species, to all of that species, and always; see
Porphyry, “Isagoge,” in Five Texts on the Mediaeval Problem of Universals: Porphyry,
Boethius, Abelard, Duns Scotus, Ockham, trans. and ed. Paul Vincent Spade
(Indianapolis, Ind.: Hackett Publishing Company, Inc., 1994), 10.
24
“For if any accident exists in a subject always and out of necessity, it must be
because it has a cause in the subject; once the subject is supposed, it is impossible for the
accident not to exist. This can indeed happen in two ways: in one way, when the
accident is caused from the principles of the species, and such an accident is called a per
se passion or a property; in another way, this happens when the accident is caused by
the principles of the individual, and this is an inseparable accident” (“Si enim aliquod
accidens ex necessitate et semper insit subiecto, oportet quod causam habeat in subiecto,
qua posita, non possit accidens non esse. Quod quidem contingit dupliciter: uno modo
quando ex principiis speciei accidens causatur, et tale accidens dicitur per se passio uel
proprium; alio modo quando accidens causatur ex principiis indiuidui, et hoc est
accidens inseparabile”) (I Post Anal., lect. 14 [Leonine ed., 1*2:53, ll. 30-39]). Reynolds
explains that “one cannot so cut off a substance from its properties, even in the mind,
that no trace of the properties is left, since the effect is latent and pre-exists in the cause.
Heat is not part of the essence of fire, and one can have first-order understanding of
what fire is without heat. But because heat flows naturally and necessarily form fire,
there must be something heat-like in the essence of fire” (Reynolds, “Properties,
Causality and Epistemological Optimism in Thomas Aquinas,” 282).
25
“Forme substantiales per se ipsas sunt ignote, set innotescunt nobis per accidentia
propria” (De Spirit. Creat., a. 11, ad 3 [Leonine ed., 24/2:121, ll. 333-35]; emphasis
added).

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us . . . the accidents themselves designate or signify the essence,
as the proper effects signify a cause.”26 This last phrase is
important, as it is not just any accidents that reveal the essence
of a thing, but rather, those accidents that are the proper effects
of a thing’s essence. These accidents, which are always found
together with the substance, are what enable some partial
knowledge of a thing’s essence, and this knowledge is possible
precisely because here there is some necessary connection, a
necessary cause-and-effect relationship. So, for example,
through a grasping of the quality of “risibility” in man, one can
begin to reason to the cause of that risibility and thus begin to
grasp something of the essence of a human being.
We must be careful here to remember that, for Thomas, the
essence of a material substance is a real composition of both
matter and form; a material essence is not a Lockean
“substance,” in the stripped-down sense of some featureless
underlying thing of which nothing can be predicated, but which
somehow unites these proper accidents.27 Rather, the essences
of material substances are precisely a unified and specified
composite of both form and matter. Per impossibile, if the
26

“Substantiales rerum differentiae sunt nobis ignotae . . . ipsa accidentia designant
vel notificant essentiam ut proprii effectus notificant causam” (De Verit., q. 10, a. 1,
ad 6 [Leonine ed., 22/2:299, ll. 278-83]; emphasis added).
27
Anscombe’s criticism of some version of understanding Aristotle’s “substance” is
applicable here, mutatis mutandis: “Such views are based on the unconscious
assumption—which we have seen in Locke—that one can identify a thing without
identifying it as a such-and-such—or that if one cannot do this, this is because we are
incapable of conceiving substance except as having some qualities. The thing, then, that
is taken to be postulated becomes a thoroughly mysterious entity which in itself has no
characteristics: a ‘somewhat we know not what’ which is postulated as underlying the
characteristics that it is said to ‘have’ and which alone enable us to conceive it. Because
Aristotle distinguishes between substance and quality, those who take a predicate like
‘man’ to signify a complex of properties readily suppose him to be distinguishing
between the being of a thing and the being of any attributes that it has. They then take
the thing itself to have no attributes. It would be almost incredible, if it had not happened, to suppose that anyone could think it an argument to say: the ultimate subject of
predication must be something without predicates; or that anyone who supposed this
was Aristotle's view could do anything but reject it with contempt” (G. E. M. Anscombe
and P. T. Geach, Three Philosophers [Oxford: Basil Blackwell, 1963], 10-11).

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essences of material substances were purely formal and immaterial, then it is true that in no way could their material,
sensible accidents tell us anything about the essences of their
substances, except perhaps their bare existence.28 But because
material essences necessarily entail matter, they are to that extent communicable to material senses.29 So although it is true
that external sensible accidents will never give us comprehensive
knowledge of a thing’s essence, nevertheless, the sensible

28

“For a cause is known through an effect either [1] by reason of a likeness that is
between the effect and cause or [2] inasmuch as an effect demonstrates the power of a
cause. But by reason of likeness, from an effect one cannot know the what it is of a
cause, unless the agent [cause] is of one species [with its effect]. . . . But by reason of
power, this also cannot be except when the effect is commensurate [adaequat] to the
power of the cause: for then, the whole power of the cause is known through the effect,
and the power of the thing demonstrates its substance” (“Nam per effectum scitur causa
vel ratione similitudinis quae est inter effectum et causam: vel inquantum effectus
demonstrat virtutem causae. Ratione autem similitudinis, ex effectu non poterit sciri de
causa quid est, nisi sit agens unius specie. . . . Ratione autem virtutis, hoc etiam non
potest esse nisi quando effectus adaequat virtutem causae: tunc enim per effectum tota
virtus causae cognoscitur; virtus autem rei demonstrat substantiam ipsius”) (ScG III,
c. 41 [Marietti ed., 2188]). “When an effect is commensurate [adaequat] to the power of
the agent, it must be that that form exists in the maker and the made according to the
same ratio; for then the maker and made would fall together in the same species”
(“Quando effectus adaequat virtutem agentis, oportet quod secundum eamdem
rationem sit illa forma in faciente et in facto; tunc enim faciens et factum coincidunt in
idem specie”) (De Pot., q. 7, a. 5 [Questiones disputate, t. 2, De potentia; De virtutibus
in communi, ed. M.-R. Cathala and Raymond M. Spiazzi, 2nd ed. (Turin and Rome:
Marietti, 1971), 59]; emphasis added).
29
The sensible matter that is part of material essences explains why, for example, it
is easier for human beings to know the nature of a rock than that of a fly: the rock has a
form that has less actuality than the fly’s, and so a rock can be more easily understood
by us through its proper, sensible, accidental forms. “For as matter, inasmuch as it is so,
is in potency, so too an agent, inasmuch as it is so, is in act” (“Sicut enim materia,
inquantum huiusmodi, est in potentia; ita agens, inquantum huiusmodi, est in actu”)
(STh I, q. 4, a. 1 [Leonine ed., 4:50]); “To the extent that a power extends itself to
many, to that degree it is more immaterial” (“Virtus quanto est immaterialior tanto ad
plura se possit extendere”) (De Verit., q. 15, a. 2, ad 7 [Leonine ed., 22/2:488,
ll. 389-90]); “Water is more material than all bodies, except earth” (“Aqua . . . inter
omnia corpora est materialior praeter terram”) (De Pot., q. 4, a. 1, ad 5 [Marietti ed.,
33]). It is important, however, to note that it does require reasoning even to grasp
something of the essence of a rock; see Super Ioan., c. 1, lect. 1 (Super evangelium S.
Ioannis lectura, ed. R. Cai (Turin and Rome: Marietti, 1952], 26).

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accidents, as they actually exist in substances, may indeed grant
some knowledge of a material essence, that is, precisely insofar
as these accidents flow from that material thing’s essence.30 It is
thus that Thomas can claim, “The ratio of a substance is known
through accidents,”31 and more precisely, “We know the substance of a thing from its properties or activities.”32
But how does the human intellect distinguish a property
from other accidents in the first place? To answer this question,
it will be helpful to review a well-known passage from Thomas’s
commentary on the Posterior Analytics. In this passage, Thomas
is trying to explain how we attain our knowledge of universal
principles, but his explanation can also be applied, mutatis
mutandis, to the attainment of the knowledge of the essences of
things. The important principle that Thomas brings into play
30

Although it is true that the external sensible accidents perceived by our senses can
never be commensurate (adaequans) to the substance that causes them, they can,
nevertheless, be commensurate to some knowledge of that material essence. “Through
its form something is seen in two ways. In one way through the form that is the thing
itself. . . . But a thing is seen through its form in another way through a form that is
from itself, whether it be abstracted from itself, as when indeed a form is more
immaterial than the thing, as the form of a stone is abstracted from a stone, or whether
it is impressed” (“Per formam autem suam aliquid dupliciter uidetur: uno modo per
formam que est ipsa res . . . alio modo per formam que est ab ipso: siue sit abstracta ab
ipso, quando scilicet forma immaterialior est quam res, sicut forma lapidis abstraitur a
lapide, siue sit impressa”) (Super Boet. De Trin., q. 1, a. 2 [Leonine ed., 50:84,
ll. 52-59]). “Indeed something is known in itself when it is known through a proper
species commensurate [adaequatam] to the knowable thing itself, as when the eye sees a
human being through the species of a human being” (“In seipso quidem cognoscitur
aliquid, quando cognoscitur per speciem propriam adaequatam ipsi cognoscibili: sicut
cum oculus videt hominem per speciem hominis”) (STh I, q. 14, a. 5 [Leonine ed.,
4:172]).
31
“Per accidentia cognoscitur ratio substantiae” (STh III, q. 75, a. 2, ad 3 [Leonine
ed., 12:160]).
32
“Substantiam rei ex proprietatibus vel operationibus eius cognoscimus” (STh I,
q. 13, a. 8 [Leonine ed., 4:157]). “Activity belongs to the composite, as also existence
belongs to the composite, for to act belongs to the existing thing. But the composite has
existence substantially through a substantial form; but it acts through the power that
follows the substantial form” (“Actio est compositi, sicut et esse: existentis enim est
agere. Compositum autem per formam substantialem habet esse substantialiter; per
virtutem autem quae consequitur formam substantialem, operatur”) (STh I, q. 77, a. 1,
ad 3 [Leonine ed., 5:237]).

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here is the role of experience (and consequently, of the cogitative power) in determining what pertains to the essence of a
thing and what is completely accidental.33
Thomas first provides us with a definition of “experience”:
“But from the memory of the same thing, made many times,
albeit in diverse singulars, comes experience; for experience
seems to be nothing other than receiving something from many
things retained in the memory.”34 Now even though human
experience certainly involves the rational power, there can be
experience in nonrational animals as well. So Thomas contrasts
experience, simply speaking, with intellectual understanding,
which nevertheless can follow from experience:
But nevertheless, experience requires some reasoning about particulars,
through which one thing is compared to another, which is proper to reason.
For example, when someone remembers that such an herb has healed many
from a fever many times, there is said to be experience that such an herb can
heal a fever. But reason does not stop in the experience of particulars, but
from many particulars in which it has experience, it receives one common
thing, which is established in the soul, and it considers that thing without
consideration of anything of singulars, and this common thing it receives as a
principle of art and knowledge. For example, so long as a doctor has
considered this herb to have healed Socrates of fever and Plato of fever and
many other individual men of fever, this is experience. But when in his

33

“For experience is from the collection of many singulars received in the memory.
But a collection of this kind is proper to human beings and pertains to the cogitative
power, which is called particular reason, which collects individual intentions, as
universal reason collects universal intentions” (“Experimentum enim est ex collatione
plurium singularium in memoria receptorum. Huiusmodi autem collatio est homini
propria, et pertinet ad vim cogitativam, quae ratio particularis dicitur: quae est collativa
intentionum individualium, sicut ratio universalis intentionum universalium”)
(I Metaphys., lect. 1 [Marietti ed., 15]).
34
“Ex memoria autem multociens facta circa eandem rem, in diuersis tamen
singularibus, fit experimentum, quia experimentum nichil aliud esse uidetur quam
accipere aliquid ex multis in memoria retentis” (II Post Anal., lect. 20 [Leonine ed.,
1*2:244, ll. 147-51]). “The cogitative acquires experience by a comparison (collatio) of
one thing to another to see what they have in common” (Mark Barker, “Experience and
Experimentation: The Meaning of Experimentum in Aquinas,” The Thomist 76 [2012]:
60).

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consideration he ascends to this, that such a species of herb heals fever simply,
this is received as a certain rule of the art of medicine. 35

In contrasting reason with experience, Thomas is not
implying that a human person has experience without the use of
his reason. Clearly, in the above example, the doctor’s intellectual power is involved throughout his acquiring knowledge
of this herb. However, so long as the doctor’s understanding of
a thing remains particular, it will bear the same name as the
“experience” that is common to animals; an animal too can be
trained to avoid or pursue a certain herb, but this is not because
it has universal knowledge. But when the doctor considers
“such a species of herb” universally and universally attributes
the accident of “fever-curing” to it, this is the activity of
reasoning that is proper to the intellectual level. In this
example, the doctor is precisely trying to discover something
about the essence of this substance, this herb. Its accident of
curing a fever is certainly accidental to the herb, in the sense
that it is not part of its essence. But, nevertheless, after
experiencing this accident many times, the doctor can begin to
ask whether this accident is a property of this specific kind of
herb, an attribute that flows from its essence and that is always
present with the herb. Experience is transformed into
intellectual reasoning about the herb’s nature when the doctor
begins to consider whether “fever-curing” is more than just
accidental simply, but instead, an accident that bears some
intrinsic connection to what the herb is. It is the reasoning that
35

“Set tamen experimentum indiget aliqua ratiocinatione circa particularia, per
quam confertur unum ad aliud, quod est proprium rationis. Puta, cum aliquis recordatur
quod talis herba multociens sanauit multos a febre, dicitur esse expertum quod talis sit
sanatiua febris. Ratio autem non sistit in experimento particularium, set ex multis
particularibus in quibus expertus est, accipit unum commune, quod firmatur in anima, et
considerat illud absque consideratione alicuius singularium. Et hoc commune accipit ut
principium artis et sciencie: puta, quandiu medicus considerauit hanc herbam sanasse
Sortem febrientem et Platonem et multos alios singulares homines, <est
experimentum>; cum autem sua consideratio ad hoc ascendit quod talis species herbe
sanat febrientem simpliciter, hoc accipitur ut quedam regula artis medicine (II Post
Anal., lect. 20 [Leonine ed., 1*2:245, ll. 152-69]).

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follows from experience then that can help us begin to
distinguish between properties and merely contingent accidents.
At this point, we should qualify the above statements by
noting that the discovery of properties in the strict sense is in
fact posterior to knowing a thing’s essence distinctly and as
such:
Because the essential forms are not known to us in themselves, they must be
shown through some accidents that are signs of that form. . . . But one must
not take the proper accidents of that species, because such must be
demonstrated through the definition of the species. But the form of the species
must be made known through some more common accidents, and according
to this, the taken differences are indeed called substantial, inasmuch as they
are brought forward in order to declare the essential form, but they are more
common than the species, inasmuch as they are taken from some signs that
follow higher genera.36

Since properties (in the strictest sense of accidents that necessarily flow from an essence and that belong only to that essence)
are known as such only through a prior knowledge of the
species, Thomas argues here that, in order to arrive at
knowledge of a species itself (i.e., knowledge of the essence of a
specific kind of thing), we must begin by focusing on features of
that essence that are in fact common to multiple species (i.e.,
36
“Quia forme essenciales non sunt nobis per se note, oportet quod manifestentur
per aliqua accidencia, que sunt signa illius forme. . . . Non autem oportet accipere
accidencia propria illius speciei, quia talia oportet per diffinitionem speciei demonstrari;
set oportet notificari formam speciei per aliqua accidencia communiora, et secundum
hoc differencie assumpte dicuntur quidem substanciales, in quantum inducuntur ad
declarandum formam essencialem, sunt autem communiores specie, in quantum
assumuntur ex aliquibus signis, qae consecuntur superiora genera” (II Post Anal., lect. 13
[Leonine ed., 1*2:222, ll. 119-31]; emphasis added). Thomas teaches this same doctrine
in his De anima commentary: “For if the essential principles could be known and rightly
defined, the definition would not lack the accidents; but because the essential principles
of things are unknown to us, we must therefore make use of accidental differences in the
designation of what is essential (for ‘two-footed’ is not essential, but it is placed in the
designation of what is essential)” (“Si enim recte diffinirentur et possent cognosci
principia essencialia, diffinitio non indigeret accidentibus; set quia principia essencialia
rerum sunt nobis ignota, ideo oportet quod utamur differenciis accidentalibus in
designatione essencialium (bipes enim non est essenciale, set ponitur in designatione
essencialis”) (I De anima, c. 1 [Leonine ed., 45/1:7, ll. 252-58]; emphasis added).

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not proper to this species alone).37 However, as Thomas
continues to explain in this same lecture, these more common
attributes must still be necessary and universal features of a
thing—even if not necessarily unique properties of the species—
if they are to help in pinning down what is both essential and
specific to a thing’s nature.38 So, for example, someone trying to
understand the essence of a horse might first discover and
collect together such necessary features as “four-legged,”
“mammal,” “grass-eating,” “hoofed,” “one-toed,” and so on, in
order to be able to arrive eventually at some working definition
of the essence of a horse, even though none of these attributes
in themselves are unique to that species of animal.39 But
37
The claim here is that essence is disclosed through the discovery of what can be
predicated as “differences,” which are indeed predicated essentially, as “a part of what
the thing was to be” (Porphyry, “Isagoge” [Spade, ed., 10]). Properties, on the other
hand, are not a part of the essence itself—they are not part of what the thing is—but
instead, they flow from the essence and as such are not discovered to be properties as
such until it is demonstrated that they are indeed proper to that specific nature.
Nevertheless, as shown above, before they are demonstrated to be properties, they can
in fact help the intellect to reason to what is essential.
38
“Because those things that are predicated in the that which it is are in it
necessarily, but whatever exists in it necessarily is predicated universally, it is necessary
that . . . those things that are predicated in the that which it is in the aforementioned
way are predicated universally and out of necessity” (“Quod ea que predicantur in eo
‘quod quid est’ ex necessitate insunt, quecunque autem ex necessitate insunt,
uniuersaliter predicantur, necesse est quod . . . accipiantur predicto modo ea que
predicantur in eo quod quid, quod ex necessitate et uniuersaliter predicentur”) (II Post
Anal., lect. 13 [Leonine ed., 1*2:222, ll. 139-41]).
39
As another example, Thomas often offers “two-footed animal” as the definition of
man, pointing out that “two-footed” is here predicated of man as a difference while
“animal” is predicated as a genus (see especially VII Metaphys., lect. 12); however, it is
obvious in this example that man is not the only species that could be defined as “twofooted animal,” and other differences must be supplied before one can arrive at a more
distinct knowledge of man’s essence. “For as much as we fully consider a thing’s
differences from others, so much will we more perfectly know each thing. For each
thing has in itself a proper existence that is distinct from all other things. Hence also, in
things of which we know the definitions, we first gather them together in a genus,
through which we know what is in common. And afterwards, we add differences, by
which something is distinguished from other things. And thus the complete knowledge
of the substance of a thing is perfected” (“Tanto enim unumquodque perfectius
cognoscimus, quanto differentias eius ad alia plenius intuemur: habet enim res

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nevertheless, from a definition reached in this manner, one
could then begin to try to discern those accidents that are truly
proper to the nature of that specific animal.40
Thus, for Thomas, human knowledge of the essence of a
specific substance is obtained gradually and is necessarily subject
to growth and development, both by the process of distinguishing those accidents that have an intrinsic relationship to a
thing’s essence from those that do not and by distinguishing
those attributes that are necessary, but common and remote,
from those attributes that are truly proper to the species. This
need to work continually on developing one’s knowledge of
even material things explains Thomas’s well-known claim that
“our knowledge is so weak that no philosopher could perfectly
investigate the nature of one fly; hence one reads that one
philosopher spent thirty years in solitude that he might know
the nature of the bee.”41
unaquaeque in seipsa esse proprium ab omnibus aliis rebus distinctum. Unde et in rebus
quarum definitiones cognoscimus, primo eas in genere collocamus, per quod scimus in
communi quid est; et postmodum differentias addimus, quibus a rebus aliis distinguatur;
et sic perficitur substantiae rei completa notitia”) (ScG I, c. 14 [Marietti ed., 117]). Cf.
STh I, q. 85, a. 3 (Leonine ed., 5:336).
40
In this article, I am primarily concerned with how we first attain knowledge of the
essences of substances, but a further account of how that knowledge is developed and
perfected according to Thomas would necessarily entail a description of how we arrive
at knowledge via the way of analysis/resolution and the way of synthesis/composition
(see Benjamin Block, “Thomas Aquinas on How We Know Essences: The Formation
and Perfection of Concepts in the Human Intellect” [PhD. diss., The Catholic University
of America, 2019], chap. 5). Briefly, one could describe the process of the development
of intellectual knowledge thus: in the act of intellectual abstraction, we arrive at a
universal intelligible species, and this is by way of resolution, for the universal
intelligible species acts as a principle for further understanding. But that intelligible
species can be made more perfect and distinct (cf. ScG II, c. 75 [Marietti ed., 1557-58]).
Thus, in our further reasoning about various natures, we discover their various
properties and features, and by way of composition, we bring together the various
principles and causes that we have apprehended in order to understand these natures
better. Finally, in the perfection of our knowledge, we understand what we know in
light of the highest, simplest principles, and this is again by way of resolution. See also
Eileen Sweeney’s excellent article on this subject: “Three Notions of Resolutio and the
Structure of Reasoning in Aquinas,” The Thomist 58 (1994): 197-243.
41
“Sed cognitio nostra est adeo debilis quod nullus philosophus potuit unquam
perfecte investigare naturam unius muscae: unde legitur, quod unus philosophus fuit

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The above examples reinforce the important point that the
idea of essence is not something “added” posteriorly to the
experience of proper accidents, as if a material being’s essence
were something completely inaccessible to our knowledge.
Instead, in and through our experience, there is first a general
intellectual understanding of a substance’s essence, and it is this
general understanding that must then gradually be made more
determinate. For Thomas, even though one’s understanding of a
specific kind of essence is developed gradually and through a
process of reasoning, one must still begin one’s knowledge of a
material substance with a more confused and general understanding of its essence:
It must be known that whether a thing exists [an est] can be known about no
thing unless in some way what it is [quid est] is known about the thing, either
in perfect knowledge or at least in a confused knowledge. . . . For he who
knows that human being exists, and who seeks to know what human being is,
must know through a definition what this name “human being” signifies. Nor
could this be unless in some way he conceived some thing that he knows
exists, even if he didn’t know its definition. For he conceives human being
according to the knowledge of some proximate or remote genus and its
accidents that externally appear from it. For the knowledge of definitions, as
also of demonstrations, takes its beginning from some preexisting
knowledge.42
triginta annis in solitudine, ut cognosceret naturam apis” (In symbolum apostolorum,
prol. [Opuscula theologica, t. 2: In Symbolum Apostolorum, scilicet "Credo in Deum"
expositio, ed. R. M. Spiazzi, 2nd ed. (Turin and Rome: Marietti, 1953), 864]).
42
“Sciendum quod de nulla re potest sciri an est nisi quoquo modo sciatur de ea quid
est, uel cognitione perfecta, uel saltem cognitione confusa. . . . Oportet enim scientem
hominem esse et quaerentem quid est homo per diffinitionem scire quid hoc nomen
‘homo’ significat. Nec hoc esset nisi aliquam rem quoquo modo conciperet quam scit
esse, quamuis nesciat eius diffinitionem: concipit enim hominem secundum cognitionem
alicuius generis proximi uel remote, et aliquorum accidentium que extra apparent de
ipso. Oportet enim diffinitionum cognitionem sicut et demonstrationum ex aliqua
preexsistenti cognitione initium sumere” (Super Boet. De Trin., q. 6, a. 3 [Leonine ed.,
50:167, l. 114-168, l. 129]; emphasis added). “The Philosopher says that what is clear
and certain to us is at first more confused, but afterwards we know in distinguishing the
principles and elements distinctly. But it is clear that to know something in which many
things are contained, without having proper knowledge of each of those things that are
contained in it, is to know something under a certain confusion” (“philosophus dicit, in
I Physic., quod sunt primo nobis manifesta et certa confusa magis; posterius autem

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The question remains then: How do we attain this “general
intellectual understanding of a substance’s essence,” which is
later developed? It is this question that we will take up in the
following section.
At this point, however, it will be helpful to review what we
have established thus far. I have made two major claims in
regard to the intellect’s attainment of the knowledge of the
essences of substances and attributed these principles to
Thomas. (1) First, the intellect’s knowledge of substance is prior
to the knowledge of accidents in general; as such, accidents are
known only in distinction from substances. However, the
knowledge of substance that is prior here is an indistinct and
general notion of substance, not a knowledge of a specific kind
of substance. (2) Second, when it comes to the knowledge of a
specific kind of substance, that is, of the essence of a particular
species, the knowledge of its accidents will be prior to the
distinct knowledge of that essence itself; knowledge of a specific
kind of substance is gained, in part, by distinguishing between
accidents that have a necessary relation to a thing’s essence and
accidents that do not. As for the knowledge of specific kinds of
substances, as we have shown above, some sort of inference
theory43 seems to be a good candidate for explaining how
cognoscimus distinguendo distincte principia et elementa. Manifestum est autem quod
cognoscere aliquid in quo plura continentur, sine hoc quod habeatur propria notitia
uniuscuiusque eorum quae continentur in illo, est cognoscere aliquid sub confusione
quadam”) (STh I, q. 85, a. 3 [Leonine ed., 5:336]).
43
I wish here to draw readers’ attention to the inference theory of Richard of
Mediavilla in particular, who wrote soon after the death of Thomas and was greatly
influenced by him. I believe that the inference theory explicitly expounded by Richard
can be found at least implicitly in Thomas, albeit with important differences discussed
further in this article (for more on Richard’s theory, see Block, “Thomas Aquinas on
How we Know Essences,” chap. 4). Richard provides a carefully thought-out account of
how we might arrive at the knowledge of a particular substance through its sensible
accidents: “We do not know substance through its proper species . . . but through its
properties, in arguing from that which in those things is some likeness of the substance,
but nevertheless not in a univocal way. For through the species of the accidents that are
received in the intellect through the mediation of the sense, the intellect knows the
intention of a dependent being. And from this, in argumentation, the intellect concludes
that for that being there is naturally some subsistent being. And finally, it concludes that

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Thomas thinks one attains this kind of knowledge.44 Again
though, for Thomas, simply parsing between those accidents
being is subsistent in itself, and it arrives at knowledge of the substance whose ratio is
being existent in itself. Afterwards, from these properties it further hunts for the
differences of substance and can only proceed inasmuch as it can draw from these
properties. . . . Hence also, when philosophers hunted for the differences of substances,
they made this from the comparison of substances to their properties and only
descended to them inasmuch as the properties could lead them by the hand. And anyone
can experience this way of knowing for himself. For if he is asked how he ought to
respond to ‘what is fire,’ he would say that it is a being existing in itself, naturally
subject to dimensions and naturally apt for heat and dryness and lightness, and so on
from its other properties. And it is evident that if man could otherwise know the
differences of substances other than through a comparison to properties, he could
otherwise express them” (“Non cognoscimus substantiam per propriam eius speciem,
sed per suas proprietates argumentando eo quod in illis est aliqua similitudo substantiae,
non tamen modo univoco. Per species enim accidentium quae mediante sensu
recipiuntur in intellectu, cognoscit intellectus intentionem entis dependentis. Et ex hoc
argumentando concludit quod illi enti natum est aliquod ens subsistere. Et tandem
concludit illud ens esse per se subsistens et devenit in cognitionem substantiae, cuius
ratio est ens per se exsistens. Postea ex illis proprietatibus ulterius venatur differentias
substantiae et tantum potest procedere, quantum potest ex illis proprietatibus elicere et
non plus naturaliter et de communi lege. Unde et philosophi cum venebantur
differentias substantiarum, hoc faciebant ex comparatione substantiarum ad earum
proprietates et tantum descendebant quantum per proprietates poterant manuduci. Et
hunc modum cognoscendi potest homo experiri. Si enim requisitus debeat respondere:
quid est ignis, dicet quod est ens per se existens natum subdi dimensionibus et aptum
natum ad caliditatem et siccitatem et levitatem, et sic de aliis proprietatibus eius. Et
constat quod, si homo aliter posset cognoscere differentias substantiae quam per
comparationem ad proprietates, aliter posset eas exprimere”) (Richard of Mediavilla, II
Sent., d. 24, p. 3, q. 3 [Clarissimi theologi magistri Ricardi de Media Villa seraphici ord.
min. convent. super quatuor libros Sententiarum Petri Lombardi Quaestiones
subtilissimae (Brescia, Italy: Vincentium Sabbium, 1591), 100vb-101ra]; translation and
emphasis mine). I am grateful to Timothy Noone for pointing out this text from
Richard of Mediavilla; the Latin text in this footnote was transcribed by him. Cf.
Timothy Noone, “The Problem of the Knowability of Substance: The Discussion from
Eustachius of Arras to Vital du Four,” in Philosophy and Theology in the Long Middle
Ages: A Tribute to Stephen F. Brown, ed. Kent Emery, Jr., Russell L. Friedman, and
Andreas Speer (Boston: Brill, 2011), 63-89.
44
“We do not know most properties of sensible things, and in most things we cannot
perfectly discover the rationes of these properties that we apprehend by the sense”
(“Rerum enim sensibilium plurimas proprietates ignoramus, earumque proprietatum
quas sensu apprehendimus rationes perfecte in pluribus invenire non possumus”) (ScG I,
c. 3 [Marietti ed., 18]). “Hence he adds that again in these things, namely in man and in

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that flow from the essence and those accidents that do not
cannot be the complete story when it comes to the knowledge
of the essences of substances. For it is still necessary to account
for how we attain to a general knowledge of the essences of
substances in the first place.
III. A PROPOSED THOMISTIC SOLUTION:
GENERAL KNOWLEDGE OF ESSENCES OF SUBSTANCES
Unless we propose that Thomas’s theories are internally
inconsistent or contradictory, we cannot claim that he has a
pure inference theory for the knowledge either of being or of
substance in general. For an accident, proper or not, is still not
a part of the essence itself, and if the proper object of the
intellect is the essences of things, there must still be some sense
in which what is first grasped is the essence of a substance, even
if this is so only in a vague and general manner. In other words,
for Thomas, the general and indistinct knowledge of a substantial essence cannot be merely the careful piecing together of
accidents unless, again, we are to admit of some incoherence or
contradiction between his different claims.
In order to explain how the initial intellectual knowledge of
substance is attained in the first place, it will be helpful to look

horse, the soul stands in its consideration until it discovers something indivisible in
them, which is the universal. As for example, we consider this animal and that animal,
say man and horse, until we arrive at animal in common, which is the genus. And in this
genus we do similarly until we arrive at some higher genus. Because therefore we receive
universal knowledge from singulars, he concludes that it is manifest that it is necessary
to know the first universal principles through induction. For thus, namely by way of
induction, the sense makes the universal internal in the soul, inasmuch as all singulars
are considered” (“Vnde subdit quod iterum in hiis, scilicet in homine et equo, anima stat
per considerationem quousque inueniatur aliquid impartibile in eis, quod est uniuersale,
ut puta consideramus tale animal et tale, puta hominem et equum, quousque
perueniamus ad commune animal, quod est genus; et in hoc similiter facimus quousque
perueniamus ad aliquod genus superius. Quia igitur uniuersalium cognitionem accipimus
ex singularibus, concludit manifestum esse quod necesse est prima uniuersalia principia
cognoscere per inductionem: sic enim, scilicet per uiam inductionis, sensus facit
uniuersale intus in anima, in quantum considerantur omnia singularia”) (II Post Anal.,
lect. 20 [Leonine ed., 1*2:246, ll. 273-87]).

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more closely at the activity of the cogitative power, for Thomas
thinks that this internal sense power also somehow attains
knowledge of substances, albeit only on the material, particular
level. If we can present a coherent picture of how the cogitative
power attains some knowledge of particular substances, then we
will also understand better how the intellect can attain some
general knowledge of substances on the universal level, prior to
its attainment of the intellectual knowledge of a specific kind of
substance.
One might reasonably object that attributing this role of
knowing substances to the cogitative power is simply moving
the problem back a step without actually solving it. Let it be
granted that the cogitative power receives particular knowledge
of substances, which would allow the intellect the possibility of
a universal knowledge of substance (which we could reason to
either by means of an a fortiori argument or by positing that the
agent intellect simply abstracts the cogitative power’s phantasm
of a particular substance).45 Even so, how can the cogitative
power itself receive knowledge of any substances in the first
place, since it too must ultimately be actualized by the external

45

Mark Barker argues that the activity of the cogitative power, in its formation of an
experiential notion, is absolutely necessary prior to the intellect’s act of abstraction;
whether or not the cogitative power’s activity is absolutely necessary, I think he is
correct in positing that its activity is in fact temporally prior to the first act of
intellectual abstraction, though the question can be answered either way without
affecting my argument here. “The standard account of Thomistic epistemology omits
the intermediary experiential notion, presenting instead a direct passage from a singular
phantasm to a universal concept. While this would require further discussion, Aquinas
explicitly teaches the contrary in at least one text” (Barker, “Experience and
Experimentation,” 69 n. 78). The text he refers to reads as follows: “It is impossible for
a universal to be looked at without induction. And this is indeed clearer in sensible
things, because through experience, which we have about singular sensible things, we
receive a universal knowledge” (“Inpossibile est uniuersalia speculari absque inductione.
Et hoc quidem in rebus sensibilibus est magis manifestum, quia in eis per experienciam
quam habemus circa singularia sensibilia, accipimus uniuersalem noticiam”) (I Post
Anal., lect. 30 [Leonine ed., 1*2:109, ll. 40-45]).

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113

sense powers?46 We must keep this objection in mind
throughout the presentation that follows.
For Thomas, the cogitative power allows one to perceive
what is only per accidens sensible, although indeed, in a particular fashion.47 What might seem surprising, however, is that it is
individual substances that Thomas calls “per accidens sensible,”
and Thomas is also explicit in saying that the cogitative power
itself knows individual substances as its proper and per se object,
at least in some manner.48 We see this teaching in his early
Sentences commentary:
46
“Accidents and motion and privations have little or nothing of being; and
nevertheless, these are more known to us than the substances of things, because they are
closer to the sense, since they fall per se under sense as the proper or common sensibles”
(“Accidentia et motus et privationes parum aut nihil habent de entitate; et tamen ista
sunt magis nota quo ad nos quam substantiae rerum, quia sunt viciniora sensui, cum per
se cadant sub sensu quasi sensibilia propria vel communia”) (VII Metaphys., lect. 2
[Marietti ed., 1304]).
47
Cf. II De Anima, c. 13 (Leonine ed., 45/1:121, l. 191-122, l. 222); II Post. Anal.,
lect. 20 (Leonine ed., 1*2:244, l. 88-246, l. 287); STh I, q. 78, a. 4 (Leonine ed.,
5:255-56).
48
“Aristotle called the concomitant perceptible objects per accidens or incidental
sensibles, because they are non-sensible features of realities that are apprehended
concurrently with the essential sensibles grasped by acts of external sensation. . . . While
such perceptible objects are incidental to essential sensibles, when taken in themselves
these per se perceptible and potentially intelligible features of reality were called
particular intentions (intentiones) by Avicenna and Thomas Aquinas, and were often
called non-sensed intentions (intentiones nonsensatae) by various Scholastics. These per
se particular intentions specify a formal object that belongs to the spectrum of cognitive
operations that Aquinas used to differentiate an internal sense power called ‘natural
instinct’ or the ‘estimative power’ in nonhuman animals, and the ‘cogitative power,’
‘particular reason,’ and the ‘passive intellect’ in human beings” (Daniel D. De Haan,
“Perception and the vis cogitativa: A Thomistic Analysis of Aspectual, Actional, and
Affectional Percepts,” American Catholic Philosophical Quarterly 88 [2014]: 402-3);
“The aspectual identification of a sensible manifold involves a perceptual apprehension
of an individual as an individual, that is, the apprehension of the sensible gestalt as more
[than] just bare per se sensibles. In perception one is able to discern, register, or become
acquainted with a superficial identity or aspect determination beyond the raw per se
sensibles, hence the term aspectual percept” (ibid., 414); “This faculty provides the
possibility for the awareness of an individual of a natural kind on the level of
perception. This, in turn, renders the entire abstraction process, which is part of the
intellect, more coherent. Given this analysis, Aquinas holds that the vis cogitativa is a
necessary component between sense perception and thought through abstraction”

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Something that is sensed per accidens does not produce a passion of the sense,
neither insofar as it is a sense nor insofar as it is this sense, but rather, what is
sensed per accidens is joined to those things that produce a passion of the
sense per se, such as Socrates, and the son of Diarius, and friend, and other
things of this kind, which are known per se, as universals in the intellect, and
as particulars in the cogitative power in human beings and in the estimative
power in other animals. But then the external sense is said to sense things of
this kind, although per accidens, when from what is sensed per se, the
apprehensive power (to which it belongs to know what is known per se)
immediately apprehends without doubt and discourse, as when we see
someone is alive from the fact that he speaks.49

Note that Thomas is saying that particular substances, such as
Socrates or a friend, are known by the cogitative power, not
incidentally, but per se, even though the cogitative power is one
of the sense powers. We must be careful here, for certainly, the
cogitative power does not grasp particular substances “as such”
(i.e., the power cannot provide the universal knowledge
necessary to understand that these particular substances are
instances of the genus substance)50 but it does grasp, as its
(Anthony Lisska, “A Look at Inner Sense in Aquinas: A Long-Neglected Faculty
Psychology,” Proceedings of the American Catholic Philosophical Association 80 [2007]:
16).
49
“Per accidens autem sentitur illud quod non infert passionem sensui neque
inquantum est sensus, neque inquantum est hic sensus; sed conjungitur his quae per se
sensui inferunt passionem; sicut Socrates, et filius Diaris, et amicus, et alia hujusmodi:
quae per se cognoscuntur in universali intellectu; in particulari autem in virtute
cogitativa in homine, aestimativa autem in aliis animalibus. Hujusmodi autem tunc
sensus exterior dicitur sentire, quamvis per accidens, quando ex eo quod per se sentitur,
vis apprehensiva, cujus est illud cognitum per se cognoscere, statim sine dubitatione et
discursu apprehendit; sicut videmus aliquem vivere ex hoc quod loquitur” (IV Sent.,
d. 49, q. 2, a. 2 [Opera omnia, t. 7/2, Commentum in quartum librum Sententiarum
magistri Petri Lombardi (Parma: Typis Petri Fiaccadori, 1858), 1202a]; emphasis
added).
50
“However much existence [esse] might be in sensible things, nevertheless the sense
does not apprehend the ratio of existence, or the intention of being [ens], as neither
does it apprehend any substantial form, except accidentally” (“Quamvis esse sit in rebus
sensibilibus, tamen rationem essendi, vel intentionem entis, sensus non apprehendit,
sicut nec aliquam formam substantialem, nisi per accidens”) (I Sent., d. 19, q. 5, a. 1,
ad 6 (Mandonnet, ed., 1:489). “But the sense does not know existence except under the
here and now” (“Sensus autem non cognoscit esse nisi sub hic et nunc”) (STh I, q. 75,
a. 6 [Leonine ed., 5:204]). “Strictly speaking, what is perceived is an existent rather than

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proper objects, individual beings that subsist in themselves
(individual substances), rather than merely sensing accidents or
a compilation of accidents.
Thomas repeats this same teaching, in much more explicit
terms, in his later De anima commentary. First, he lays out two
important qualities that belong to everything that is per accidens
sensible, and then he notes that what is per accidens sensible is
still per se known by another knowing power:
It must be known therefore, that in order for something to be sensible per
accidens, it is first required that it is accidental to that which is per se sensible,
as it is accidental to white that it is a man, and it is accidental to it that it is
sweet. Second, it is required that it is apprehended by the one sensing; for if
what was accidental to what is sensible were hidden from the one sensing, it
would not be called per accidens sensible. It must be the case therefore that it is
known per se by some other knowing power of the one sensing. And this
indeed is either another sense, or the intellect, or the cogitative power (or
estimative power).51

Since particular substances are per accidens sensible, it is clear
from this passage that they must be accidental to the per
se sensibles, such as color and taste, inasmuch as they are not
passions of the external sense powers as such. Nevertheless, as
we will show below, being sensible per accidens does not
preclude any necessary relation at all between particular
substances and what is per se sensible. Furthermore, this passage
explains again that particular substances, even though per
accidens sensible, are still known per se by another knowing

existence as such. Hence such knowledge of existence is still only implicit. Existence will
not be singled out or isolated as such for consideration at the level of the senses. But the
raw material is now at hand for the intellect to advert to the fact that the senses are
perceiving some object and for it to judge that the thing in question actually exists”
(Wippel, Metaphysical Thought of Thomas Aquinas, 36).
51
“Sciendum est igitur quod ad hoc quod aliquid sit sensibile per accidens primo
requiritur quod accidat ei quod est per se est sensibile, sicut accidit albo esse hominem
et accidit ei esse dulce, secundo requiritur quod sit apprehensum a senciente: si enim
accideret sensibili quod lateret sencientem, non diceretur per accidens sentiri. Oportet
igitur quod per se cognoscatur ab aliqua alia potencia cognoscitiua sencientis, et hec
quidem uel est alius sensus, uel est intellectus, uel uis cogitatiua aut uis estimatiua”
(II De Anima, c. 13 [Leonine ed., 45/1:120, ll. 164-74]; emphasis added).

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power, which, as Thomas goes on to explain, is precisely the
cogitative power:
What is not known properly by a sense therefore, if it is something universal,
is apprehended by the intellect. Nevertheless, not everything that is able to be
apprehended in the sensed thing by the intellect can be called sensible per
accidens, but only that which is immediately apprehended by the intellect
when it meets with the sensed thing. As, for example, when I immediately see
someone speaking or moving himself, I apprehend his life through the intellect
and hence can say that I see he is alive. But if something is apprehended in the
singular, as, for example, when I see something colored I perceive this man or
this animal, then apprehension of this kind in human beings takes place
through the cogitative power, which is also called particular reason, from the
fact that it gathers together individual intentions, just as universal reason
gathers together universal rationes. Notwithstanding, this cogitative power is
nevertheless in the sensitive part, because the sensitive power in its highest
form participates something of the intellective power in human beings, who
have the sense joined to the intellect.52

Thus, though Thomas knows full well that the cogitative power
belongs to the sensitive part of the soul, he continues to affirm
that individual substances, rather than accidents, are per se
known by the cogitative power. Note that Thomas also echoes
the Sentences commentary here in insisting that a per accidens
sensible is immediately perceived together with the per se sensibles, prior to any reasoning or comparison that might take
place in either the intellect or the cogitative power.
As Thomas also explains here, the fact that something is per
accidens sensible does not further entail that the connection
52

“Quod ergo sensu proprio non cognoscitur, si sit aliquid uniuersale, apprehenditur
intellectu. Non tamen omne quod intellectu apprehendi potest in re sensata, potest dici
sensibile per accidens, set quod statim ad occursum rei sensate apprehenditur intellectu,
sicut statim cum uideo aliquem loquentem uel mouere se ipsum, apprehendo per
intellectum uitam eius, unde possum dicere quod uideo eum uiuere. Si uero
apprehendatur in singulari, ut puta <si>, cum uideo coloratum, percipio hunc
hominem uel hoc animal, huiusmodi quidem apprehensio in homine fit per uim
cogitatiuam, que dicitur etiam ratio particularis, eo quod est collatiua intentionum
indiuidualium sicut ratio uniuersalis est collatiua rationum uniuersalium, nichilominus
tamen hec uis est in parte sensitiua, quia uis sensitiua in sui suppremo participat aliquid
de ui intellectiua in homine, in quo sensus intellectui coniungitur” (II De Anima, c. 13
[Leonine ed., 45/1:121, l. 182-122, l. 201]; emphasis added).

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117

between what is per se sensed and the substance that underlies
the per se sensible is only contingent: “Whether that which is
the subject of a sensible quality is per se its subject or not, this
makes no difference as to whether or not a thing is itself per
accidens sensible. For no one would say that fire, which is the
proper subject of heat, is per se sensible to touch.”53 In other
words, the term “per accidens sensible” should not mislead us
into thinking that what we know per se through our external
senses is only purely accidentally predicated of the substances in
which these sensible qualities exist. There may indeed be a
necessary connection here, and indeed, the fact that there is a
substance or substances underlying accidents is something that
Thomas considers manifest, even at a nonintellectual level: “A
substance of this kind is apparent, that is, clear, since it is
subject to sense. And therefore, one ought not to delay the
knowledge of it.”54
Above, I brought up the objection that attributing the
knowledge of particular substances to the cogitative power was
simply moving the problem back a step. In the response to this
objection that follows, it is important to remember that, just as
Thomas does not suppose an unerring knowledge of any
specific kind of substance in the intellect, neither does he
suppose an unerring knowledge of any particular substance in
the cogitative power. In fact, he claims explicitly that “the
judgment of sense sometimes errs in regard to the common
sensibles or the per accidens sensibles.”55 Furthermore, the fact
that the cogitative power per se perceives the so-called “per
accidens sensibles” does not entail that it cannot err in regard to
its particular judgment about them in any way, for indeed, the
53
“Non enim refert ad id quod est sensibile per accidens utrum id quod est
subiectum sensibilis qualitatis sit per se subiectum eius uel non per se; nullus enim
diceret ignem, quod est proprium subiectum caloris, esse per se sensibile tactu” (ibid.
[Leonine ed., 45/1:120, ll. 119-24]).
54
“Huiusmodi substantia <<est aperta>>, idest manifesta, cum sensui subiaceat. Et
ideo circa eius cognitionem non oportet immorari” (VII Metaphys., lect. 2 [Marietti ed.,
1296]).
55
“De sensibilibus communibus vel per accidens interdum iudicium sensus fallitur”
(De Verit., q. 1, a. 11 [Leonine ed., 22/1:35, ll. 112-13]).

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common sensibles too, about which the sense may also err, are
also perceived per se.56 Similar to the way in which the intellect
knows the essences of particular species with scientific knowledge only after a process of reasoning, the cogitative power
knows particular substances with a degree of certitude only after
a process of “particular reasoning” and experience. Yet,
nevertheless—and this is crucial to Thomas’s epistemology—as
the intellect does not fail to recognize being in general, even in
its initial act of understanding, so too, the cogitative power does
not fail to recognize some particular “underlying substance” or
“underlying substances” through the sensible accidents perceived by the external sense powers.57 More precisely, although
the cogitative power may indeed err in its grasp of any
particular substance (though it is no small matter that for the
most part it correctly grasps something of these substances), and
though it may indeed err in its judgment that any particular
substance exists, in any case, it does not err in recognizing some
particular substance existing and causing the sensible accidents;
that is, the cogitative power does not err in understanding that

56

“The common sensibles are not sensed per accidens by any of the senses, but they
are sensed per se by many” (“Sensibilia communia non senciuntur per accidens ab aliquo
sensuum, set per se a pluribus”) (III De Anima, c. 1 [Leonine ed., 45/1:175, ll. 156-58]).
57
We should note here again that although both the intellect and the cogitative
power collect and compare universal and particular intentions, respectively, what is per
accidens sensible is only what is immediately apprehended by these powers when
sensible things are sensed: “Nevertheless, not everything in the sensed thing that is able
to be apprehended by the intellect is able to be called sensible per accidens, but rather
what is immediately apprehended by the intellect upon meeting the sensed thing” (“Non
tamen omne quod intellectu apprehendi potest in re sensata, potest dici sensibile per
accidens, sed quod statim ad occursum rei sensate apprehenditur intellectu”) (II De
Anima, c. 13 [Leonine ed., 45/1:121, ll. 184-87]). But as we have already established,
what is immediately apprehended by the intellect, before reasoning, is not infallible
knowledge of a specific essence, though the intellect does perceive being and essence in
general; similarly, what is immediately apprehended by the cogitative power is not
infallible knowledge about a particular substance or that a particular substance exists,
since it too may err in this regard and must “reason” about what it perceives; rather, the
cogitative power immediately perceives infallible knowledge of some “particular
substance” that necessarily underlies the per se sensible.

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119

there is some substance in some way underlying the sensible
accidents.
For example, if one were to see a moving shadow in the
distance, one might indeed mistake, purely at the sense level,
the object to be a substance or substances that it is not actually.
But one would not be mistaken in recognizing immediately that
there must be a substance that underlies that motion and that
causes that shadow.58 Thomas notes that there are certain
“things about which it is necessary to know first that they are,
such as principles,”59 and in the case of the cogitative power,
every individual experience of a substance is a principle for that
power’s further development in its knowledge of particular
things:
And it is clear that singulars have the ratio of principles because the universal
is received from singulars. For, from the fact that this herb causes health for
this one, it is received that this species of herb has the power of healing. And
because singulars are properly known through sense, it must be that in regard
to these singulars, which we say are principles and extremes, man has sense
[knowledge], not only external sense but also internal sense, which above he
[Aristotle] said was prudence, namely, the cogitative or estimative power,
which is called particular reason.60

58

But what if one is crazy and merely imagining that something moved when there is
nothing externally happening at all? We must recall that Thomas is not concerned here
with the modern project of justifying an absolute subjective certainty; the senses are here
assumed to be healthy and operating normally. “For as natural powers do not fail from
their proper activities, except in the least part, because of some corruption, so too, the
senses do not fail from the true judgment of proper sensibles, except in the least part,
because of some corruption of the organ” (“Sicut enim potencie naturales non deficiunt
a propriis operationibus nisi in minori parte propter aliquam corruptionem, sic et sensus
non deficiunt a uero iudicio propriorum sensibilium nisi in minori parte propter
aliquam corruptionem organi”) (II De Anima, c. 30 [Leonine ed., 45/1:198, ll. 65-70]).
59
“Alia sunt de quibus necesse est prius cognoscere quia sunt, sicut principia” (I Post
Anal., lect. 2 [Leonine ed., 1*2:11, ll. 54-55]; emphasis added).
60
“Et quod singularia habeant rationem principiorum, patet quia ex singularibus
accipitur universale; ex hoc enim quod haec herba fecit huic sanitatem, acceptum est
quod haec species herbae valet ad sanandum. Et, quia singularia proprie cognoscuntur
per sensum, oportet quod homo horum singularium quae dicimus esse principia et
extrema, habeat sensum non solum exteriorem, sed etiam interiorem, cuius supra dixit
esse prudentiam, scilicet vim cogitativam sive aestimativam quae dicitur ratio
particularis” (VI Ethic., lect. 9 [Leonine ed., 47/2:367, ll. 173-84]).

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Thus, what Thomas says in his Physics commentary is borne
out, namely, that even on the level of sense knowledge, which
knows things only as particulars, the more common is still
known prior to the less common. That is, one senses something
as a particular substance prior to sensing it as a particular
animal or a particular human.61
Since (a) Thomas unwaveringly affirms that the cogitative
power knows per se individuals that are substances and yet (b)
he acknowledges the cogitative power can err in some respects
in regard to its knowledge of particular substances, I believe I
have presented above a reasonable interpretation of Thomas’s
position on what the cogitative power knows in knowing
particular substances. Even if one grants the above presentation,
however, all that will have been established is that Thomas
thinks the cogitative power perceives individual substances, at
least in some vague manner. This does not yet fully answer the
question of how the cogitative power perceives particular
substances.62
I propose here that the reason why the cogitative power (and
a fortiori, the intellect) can attain to knowledge of substances in
this general fashion is precisely because the existence of
accidents is an existence that is caused by a substance or substances. For the existence of all accidents is always an existence
that is caused by and participates in the existence of substances;
if nothing else, the substance in which the accident inheres is at

61

“Thus, the more common sensible is known to us according to sense prior to the
less common sensible, as for example, this animal [is known prior] to this man” (“Ita
communius sensibile est prius notum nobis secundum sensum, ut puta hoc animal quam
hic homo”) (I Phys., lect. 1 [Leonine ed., 2:6]). Cf. Deborah Black, “Avicenna’s ‘Vague
Individual’ and its Impact on Medieval Latin Philosophy,” in Vehicles of Transmission,
Translation, and Transformation in Medieval Textual Culture, ed. Robert Wisnovsky
and others (Turnhout: Brepols Publishers, 2011), 259-92.
62
Before turning our attention to this question, we must be careful to note that the
question of how the cogitative power perceives substances is not at all explicitly spelled
out by Thomas himself. Thus, the explanation I am providing below must be
understood as somewhat speculative in regard to what Thomas himself thinks, though I
believe there is substantial evidence to support this interpretation.

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least that accident’s material cause.63 Thus, though it is through
the common sense that the external senses are united, it is
through the cogitative power that one recognizes the cause or
causes of the objects of the external senses (the per se sensibles),
namely, an individual substance or substances. The first proposition from the Liber de causis, and Thomas’s commentary
thereon, is key here:
Every first cause impresses more on what is caused than a second universal
cause. . . . The activity by which a second cause causes an effect is caused by
the first cause . . . therefore, the first cause is more of a cause than the second
cause of this activity, by which the effect is produced by the second cause. . . .
The first cause is more a cause than the second; therefore its power is more
perfect. But insofar as the power of any cause is more perfect, so much so will
it extend itself to more things. Therefore the power of the first cause extends
itself to more than the power of the second cause. But that which is in more
things is first in arriving and last in receding. Therefore the impression of a
first cause arrives first and recedes last.64

Thomas explains further on that this principle is true for all
kinds of causes in per se orders of causality. Now since a
substance is the cause of the accidents that inhere in it, it is thus
63
“Thomas concludes . . . by observing that a subject is in some fashion a cause of all
the accidents which are sustained within the being of that same subject” (John Wippel,
“Thomas Aquinas on Substance as a Cause of Proper Accidents,” in Philosophie im
Mittelalter, ed. Jan P. Beckmann and others [Hamburg: Felix Meiner Verlag, 1987],
203). “Throughout his career Thomas holds that a substance serves as a receiving or
material cause for the accidents which inhere in it. Hence the subject is in potency to
such accidents, and the accidents may be regarded as it its secondary acts or secondary
forms” (ibid., 211); “Proper accidents which follow upon a thing’s species are caused
efficiently by that thing’s essential and intrinsic principles. At the very least, something
more than receiving or material causality is involved” (ibid., 207-8).
64
“Omnis causa primaria plus est influens super suum causatum quam causa secunda
universalis. . . . Operatio qua causa secunda causat effectum, causatur a causa prima . . .
ergo huius operationis secundum quam effectus producitur a causa secunda, magis est
causa causa prima quam causa secunda. . . . Causa prima est magis causa quam secunda;
ergo est perfectioris virtutis. Sed quanto virtus alicuius causae est perfectior, tanto ad
plura se extendit; ergo virtus causae primae ad plura se extendit quam virtus causae
secundae. Sed id quod in pluribus est, prius est in adveniendo et ultimum in recedendo;
ergo impressio causae primae primo advenit et ultimo recedit” (Super librum De causis
expositio, ed. H. D. Saffrey [Fribourg (Suisse)-Louvain: Société Philosophique
Nauwelaerts, 1954], prop. 1, 5:1-2; 7:1-5; 8:5-11).

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also the cause of their very ability to affect the senses: “An
accidental form has the fact that it is a principle of action from a
substantial form.”65 Therefore, it is true to say, in at least some
respect, that substances leave a greater impression on the
knowing powers than their accidents and, further, that
substances arrive first in the sense powers—though it is true
that, of the sense powers, only the cogitative power perceives
substances per se. In somewhat poetic language, one could say
that the cogitative power sees through the existence of the
accidents to the presence of the substance itself. More precisely,
the cogitative power grasps the presence of the cause of the
accidents (a particular substance) together with the presence of
their effects (the accidents themselves) because it perceives the
presence of accidents precisely as a presence in a subject: “A
higher power per se looks to a more universal ratio of an object
than a lower power does, because inasmuch as a power is
higher, so much does it extend to more things.”66 The cogitative
power does not grasp the accident without grasping something
of that accident’s cause.67
There is implicit evidence for such an interpretation in
Thomas’s writings. First, we should note that it is a Thomistic
principle that every effect is like its cause (hence, we can even
naturally know God himself not only by way of causality and by

65
“Hoc ipsum quod forma accidentalis est actionis principium, habet a forma
substantiali” (STh I, q. 77, a. 1, ad 4 [Leonine ed., 5:237]).
66
“Potentia superior per se respicit universaliorem rationem obiecti, quam potentia
inferor: quia quanto potentia est superior, tanto ad plura se extendit” (STh I, q. 77, a. 3,
ad 4 [Leonine ed., 5:241]).
67
“Sense attains existence in act without itself knowing that it is existence. Sense
delivers existence to the intellect; it gives the intellect an intelligible treasure which
sense does not know to be intelligible, and which the intellect, for its part, knows and
calls by its name, which is being” (Jacques Maritain, Existence and the Existent, trans.
Lewis Galantiere and Gerald B. Phelan [Garden City, N.Y.: Image Books, 1956], 21).
“Our intellect understands existence in the way in which it discovers it in lower things,
from which it grasps scientific knowledge” (“Intellectus autem noster hoc modo
intelligit esse quo modo invenitur in rebus inferioribus a quibus scientiam capit”) (De
Pot., q. 7, a. 2, ad 7 [Marietti ed., 56]).

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123

way of negation, but also by way of eminence):68 “But it is clear
that an effect must pre-exist in its causes as in an exemplar
[exemplariter], because causes produce effects according to their
own likeness; and conversely, things that are caused have the
image of their causes.”69 Furthermore: “Each thing is known
through that which is in act; and therefore the actuality itself of
a thing is a certain light of the thing itself, and because an effect
has that it is in act through its cause, it follows that it is
illuminated and known through its cause.”70 More specifically:
“The action of an accidental form depends on the action of a
substantial form, as the existence of an accident depends on the
existence of a substance.”71 Hence, here we also have the Thomistic axiom that agere sequitur esse, activity follows existence.72 It follows that, if the existence of an accident necessarily
68

See, e.g., I Sent., d. 3, pro. (Mandonnet, ed., 88-89); STh I, q. 13, a. 1 (Leonine
ed., 4:139).
69
“Manifestum est autem quod oportet effectus praeexistere in causis exemplariter,
quia causae producunt effectus secundum suam similitudinem; et e converso causata
habent imaginem suarum causarum” (Liber de causis, prop. 14 [Saffrey, ed., 85:20-23]).
70
“Unumquodque cognoscitur per id quod est in actu; et ideo ipsa actualitas rei est
quoddam lumen ipsius et, quia effectus habet quod sit in actu per suam causam, inde est
quod illuminatur et cognoscitur per suam causam” (Liber de causis, prop. 6 [Saffrey, ed.,
45:12-15]).
71
“Ita actio formae accidentalis dependet ab actione formae substantialis, sicut esse
accidentis dependet ab esse substantiae” (STh III, q. 77, a. 3, ad 2 [Leonine ed.,
12:197]). “The actuality of an accidental form is caused by the actuality of the subject”
(“Actualitas formae accidentalis causatur ab actualitate subiecti”) (STh I, q. 77, a. 6
[Leonine ed., 5:246]).
72
“For there is no activity except of a being in act; hence, in the same way that
something acts, in that way it exists” (“Non enim est operari nisi entis in actu: unde eo
modo aliquid operatur, quo est”) (STh I, q. 75, a. 2 [Leonine ed., 5:196]). “For that by
which a thing primarily acts is its form to which the activity is attributed. . . . And the
reason for this is that nothing acts except inasmuch as it is in act; hence in the way that
something is in act, in that way it acts” (“llud enim quo primo aliquid operatur, est
forma eius cui operatio attribuitur. . . . Et huius ratio est, quia nihil agit nisi secundum
quod est actu: unde quo aliquid est actu, eo agit”) (STh I, q. 76, a. 1. [Leonine ed.,
5:208]). “Each agent acts inasmuch as it is in act” (“Unumquodque agens agit secundum
quod in actu est”) (De Pot., q. 2, a. 1 [Marietti ed., 8]). “Active power follows being in
act: for each thing acts from the fact that it is in act” (“Potentia activa sequitur ens in
actu: unumquodque enim ex hoc agit quod est actu”) (ScG II, c. 7 [Marietti ed., 888]).
“Act follows being [esse] in act” (“Agere sequitur ad esse in actu”) (ScG III, c. 69

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participates in the existence of some substance, as we have
already established, then the reception of an accidental form—
that is, the sense’s being actualized by the actuality of the
accidental form—will indeed be sufficient to provide some
knowledge of that substance to any knowing power that is penetrating enough. But indeed, as we have already seen, the higher
powers of the soul guide and direct the lowers powers as their
instruments and indeed, through the lower powers, penetrate
more deeply into the knowledge of their objects.73 This is why
Thomas sees no problem in positing that the cogitative power
properly knows individual substances, even though it may
indeed err in its “particular reasoning” about an individual
substance or about the existence of any particular substance.
We must affirm again that Thomas is not claiming that we
have an immediate, certain, and infallible knowledge of
individual substances through either the cogitative power or the
intellect. The initial knowledge gained through either the power
of the intellect or of the cogitative power does not seem to
grant any more knowledge than that there is substantial being
[Marietti ed., 2450]). “For action is properly the actuality of a power, as being [esse] is
the actuality of a substance or essence” (“Actio enim est proprie actualitas virtutis; sicut
esse est actualitas substantiae vel essentiae”) (STh I, q. 54, a. 1 [Leonine ed., 5:39]).
“The essence of the soul itself is also the principle of acting, but though a mediating
power” (“Essentia ipsius animae est etiam principium operandi, sed mediante virtute”)
(I Sent., d. 3, q. 4, a. 2, ad 2 [Mandonnet, ed., 117]). See Daniel Kambembo, “Essai
d’une ontologie de l’agir,” Revue phlosophique de Louvain 65 [1967]: 382-84, for
different interpretations of this maxim. See also Joseph de Finance, Etre et agir dans la
philosophie de saint Thomas, 2nd ed. (Rome: Università Gregoriana, 1960); William A.
Wallace, “The Intelligibility of Nature: A Neo-Aristotelian View,” The Review of
Metaphysics 38, no. 1 (1984): 33-56; W. Norris Clarke, “Action as the Self-Revelation
of Being: A Central Theme in the Thought of St. Thomas,” in idem, Explorations in
Metaphysics: Being—God—Person (Notre Dame, Ind.: University of Notre Dame Press,
1994), 45-64.
73
“Powers of the soul that are prior according to the order of perfection and nature
are the principles of the others in the mode of an end and active principles” (“Potentiae
animae quae sunt priores secundum ordinem perfectionis et naturae, sint principia
aliarum per modum finis et activi principii”) (STh I, q. 77, a. 7 [Leonine ed., 5:247]).
“The intellective powers are prior to the sensitive powers, and hence direct them and
command them” (“Potentiae intellectivae sunt priorers potentiis sensitivis: unde dirigunt
eas et imperant eis”) (STh I, q. 77, a. 4 [Leonine ed., 5:243]).

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underlying the accidents perceived by the senses. For example,
the first time that the external senses perceive the shape, color,
size, and motion of a horse, the cogitative power’s initial
perception will not be a perception of this horse in any distinct
sense, for the cogitative power does not yet have any grasp of
this substance from experience. It would be more accurate to
say that the initial perception through the cogitative power
would instead simply be that there is a particular substance or
substances underlying the accidents. In this example, if one is
already familiar with animals in general (i.e., if one has
experience of animals), then the cogitative power might further
perceive that one is sensing a particular animal here, even if it
does not have enough experience of horses to recognize
anything further than that. This is why, in the passage already
quoted above, Thomas says that, on the level of the intellect,
“the form of the species must be made known through some
more common accidents,”74 for the first time that one
experiences a horse, one will first have to come to conclusions
about this substance based upon what this kind of animal has in
common with other animals that one has experienced, in order
to determine whether and how this kind of animal differs from
them. Again, the actualization of the cogitative power has its
source in the external senses, which as such perceive only
sensible accidents, but these sensible accidents, precisely as the
effects of substance, are sufficient to provide the cogitative
power with the perception that there is some particular
substance underlying these accidents.75 But any detailed
74
“Non autem oportet accipere accidencia propria illius speciei, quia talia oportet
per diffinitionem speciei demonstrari; set oportet notificari formam speciei per aliqua
accidencia communiora” (II Post Anal., lect. 13 [Leonine ed., 1*2:222, ll. 122-26];
emphasis added). See also VIII Metaphys., lect. 2.
75
“For when any effect is more manifest to us than its cause, we proceed to the
knowledge of the cause through the effect. But from any effect one can demonstrate the
existence of its proper cause (if at least its effects are more known to us) because, since
an effect depends on a cause, if an effect is posited, it is necessary for the cause to preexist it” (“Cum enim effectus aliquis nobis est manifestior quam sua causa, per effectum
procedimus ad cognitionem causae. Ex quolibet autem effectu potest demonstrari
propriam causam eius esse [si tamen eius effectus sint magis noti quoad nos]: quia, cum
effectus dependeant a causa, posito effectu necesse est causam praeexistere”) (STh I,

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knowledge about the nature of a particular substance, such as
horseness, will of course involve the gathering together and the
experience of many particular sensations, which experience
must in turn be universalized and developed by the intellect.76
Similarly then, since the cogitative power can perceive something of an individual substance beyond its accidents (not
individual substance as such, but an individual substance as a
subject of those accidents),77 a fortiori, when the phantasm of
some particular substance is presented to the intellect, the
intellect can understand that substance in a universal manner,
and thus attain to some knowledge of the essence of a natural
substance.78 What the cogitative power can perceive on a
q. 2, a. 2 [Leonine ed., 4:30]). As we saw in the passage from III Sent., d. 35, Thomas
thinks that the way we obtain a knowledge of separated substances is analogously
similar to the way we attain to knowledge of the essences of natural things.
76
“But how this one thing is able to be received, Aristotle manifests in the following.
For it is manifest that the singular is what is sensed properly and per se, but nevertheless,
there is sensing, in a certain way, also of that universal. For one knows Callias not only
inasmuch as he is Callias, but also inasmuch as he is this man, and similarly one knows
Socrates inasmuch as he is this man. And from the fact that there is in the sense such a
pre-existing reception, the intellective soul is able to consider man in both individuals.
But if it were the case that the sense apprehended only that which is of the particular,
and in no way when it did this apprehended the universal nature in the particular, it
would not be possible that the sense in apprehension could cause in us knowledge of the
universal” (“Qualiter autem hoc unum accipi possit, manifestat consequenter.
Manifestum est enim quod singulare sentitur, proprie et per se, set tamen sensus est
quodam modo etiam ipsius uniuersalis: cognoscit enim Calliam non solum in quantum
est Callias, set etiam in quantum est hic homo, et similiter Sortem in quantum est hic
homo. Et exinde est quod, tali acceptione sensus preexistente, anima intellectiua potest
considerare hominem in utroque. Si autem ita esset quod sensus apprehenderet solum id
quod est particularitatis et nullo modo cum hoc apprehenderet uniuersalem naturam in
particulari, non esset possibile quod ex apprehensione sensus causaretur in nobis
cognitio uniuersalis”) (II Post Anal., lect. 20 [Leonine ed., 1*2:246, ll. :257-71]).
77
“Just as one cannot properly sense danger, but only dangerous things, one cannot
perceive individual identity as such by external sensation” (Mark Barker, “Aquinas on
Internal Sensory Intentions: Nature and Classification,” International Philosophical
Quarterly 52 [2012]: 215).
78
“But to our intellect according to its present state of life nothing is present as an
object, except through some likeness of it, or something received from its effect, because
through effects we arrive at the causes” (“Intellectui autem nostro nihil est secundum
statum viae praesens ut objectum, nisi per aliquam similitudinem ipsius, vel suo effectu

KNOWING THE ESSENCES OF MATERIAL SUBSTANCES

127

particular, material level, the intellect is able to perceive on a
universal, intellectual level.79 Furthermore, even in its own
initial act of apprehension in which it simply perceives being,
the intellect is able to know being precisely because it does not
merely receive the species of a sensible accident in complete
separation from that accident’s cause. The intelligible species
through which the intellect knows, even if it is a likeness of an
accident, still bears a necessary relation to substance: “In the
thing apprehended through the sense, the intellect knows many
things that the sense cannot perceive.”80 Thus, through the
intelligible species produced by the agent intellect and the
phantasm (whether of a particular accident or of a particular
substance), the intellect’s first concept is simply a general notion
of being. But the intellect subsequently makes distinctions
regarding this general notion of being, clarifying (at least implicitly and vaguely) the difference between the notions of being
that exists in itself (substance) and being that exists in another
(accidents, which again, can only be understood in light of
understanding beings that exist in themselves). But this order of
development in our concepts is possible precisely because the
senses do not perceive accidents in complete separation from
the substances in which they exist, but instead, precisely as
necessarily caused by them.

acceptam: quia per effectus devenimus in causas”) (I Sent., d. 17 q. 1, a. 4, ad 4
[Mandonnet, ed., 404]).
79
“One cannot know natures without one’s intellect, but one cannot know signate
material individuals without the cogitative. Universal reason, upon seeing a person
speaking or moving, can recognize that individual’s life. ‘Life’ is on a higher level of
abstraction than ‘human.’ It is a universal intention that is only apprehended by
intellect. Upon seeing someone speaking or moving, one’s intellect immediately
apprehends ‘life,’ and this apprehension may be followed by a judgment in which one
applies that universal notion to the individual, as in ‘I see that he is alive.’ In contrast, if
one sees a human approach, the cogitative apprehends or perceives that it is so-and-so,
and then applies this individual intention to him in a judgment such as ‘I see Socrates.’
Thus, merely seeing someone’s face provides the matter for an individual intention,
which actualizes the sensed form with respect to its knowability as belonging to a given
individual” (Barker, “Aquinas on Internal Sensory Intentions,” 215).
80
“In re apprehensa per sensum intellectus multa cognoscit quae sensus percipere
non potest” (STh I, q. 78, a. 4, ad 4 [Leonine ed., 5:256-57]).

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Before concluding this section, it will helpful to review
Thomas’s description of the acquisition of intellectual knowledge of essences, from beginning to end. The five external
senses provide sense knowledge: color, shape, motion, touch,
and so on. These external senses are united by the common
sense, which is their root and principle. The three internal sense
powers of imagination, memory, and the cogitative power are
themselves further actualized by what is received through the
senses. The cogitative power, however, attains to knowledge of
the singular thing: its knowledge is not limited to a knowledge
of merely the accidents, the per se sensibles, but it perceives that
there is a particular substance or substances underlying these
accidents. However, the products of the internal sense powers
are still particular. The action of the agent intellect on the
phantasms presented by the internal sense powers then produces impressed intelligible species, which are universal and
immaterial, but whose content is still a product of the phantasms. The very first intellectual understanding will form an
expressed species (i.e., concept) of being that will quickly be
distinguished into clearer and more distinct concepts. The
distinction between substance and accident will occur quite
early in this process, though the intellectual knowledge of substance as such is necessarily temporally prior (or at the very
least concomitant) to the knowledge of accident as such. The
knowledge of any specific kind of substance, however, will
occur through distinguishing between different kinds of accidents, with the aid of the cogitative power, and the attempt to
discover which accidents flow from a thing’s essence and which
do not.81

81
Thus, in Thomas’s epistemology, we do indeed see the “inference” picture of
Richard of Mediavilla in the attainment of the knowledge of specific kinds of
substances, but we also see that, in contrast, Thomas retains the intellect as a power that
can actually see beyond accidents, which can know being itself, even from its first act of
simple apprehension.

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CONCLUSION
This article began with a concern about the ability of our
intellect to grasp effectively the essences of things at all. Since
all our knowledge has its origin in the senses, one might
conclude that all human knowledge is merely of external
accidents or of our own activities. In the above attempt to
explain how knowledge of essences of material substances is
possible for Thomas, I have shown how, in his account, the
cogitative power and the intellect penetrate beyond the merely
accidental to the substantial natures that underlie accidents.
Nevertheless, as we know by both experience and reason, the
initial knowledge of the human intellect is quite sparse. For
Thomas, that intellect begins its journey with a completely
general grasp of the essences of things, starting from the
greatest potentiality for knowledge and from the greatest
imperfection in what it knows; it is only in reasoning about
what we conceive that our intellect is perfected. Knowledge
about the essences of specific natures requires a slow, careful
process of distinguishing and combining acts of judgment, as
well as further reasoning from those acts of judgment, and
complete subjective certainty regarding the essences of specific
natures is not a property of human knowledge in this life. This
poverty of the human intellect is why Thomas places human
beings at the very lowest rung of intellectual knowers; while
other intellectual beings are pure intellects, immediately
grasping essences, the human person requires many different
powers and activities for the little knowledge that he does
obtain.82 It is thus that our own knowledge remains at a certain
horizon between the material and the immaterial.83
Yet we should also remember that, according to Thomas, the
human soul is fittingly united to the human body.84 The human
body, from the sense power of touch to the complex nerve
82
“The human soul needs many and different activities and powers” (“Multis et
diversis operationibus et virtutibus indiget anima humana”) (STh I, q. 77, a. 2 [Leonine
ed., 5:240]).
83
Cf. ScG II, c. 68 (Marietti ed., 1453).
84
Cf. STh I, q. 76, a. 5 (Leonine ed., 5:227-28).

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systems of the human brain, is the instrument most suited for
our growth in human knowledge. It is true that we begin life as
knowers only in potency, and much of what we later think we
know is uncertain; yet there is some certainty in our intellectual
knowledge, insofar as we can have at least a general grasp of
material essences and insofar as the human intellect can
approach certainty as it continues to develop its knowledge of
specific material essences—and indeed, even as it develops its
natural knowledge of some of the properties of immaterial
beings. So long as the human intellect remains faithful to its
own nature, to the rules of logic and to the instruction of
experience, we can continue in our human hope of approaching
the perfection of our knowledge.85

85
This article has been adapted primarily from selections of chapter 4 of my
dissertation, “Thomas Aquinas on How We Know Essences: The Formation and
Perfection of Concepts in the Human Intellect.” A more thorough treatment of
surrounding epistemological issues and the historical development of these problems can
be found therein.

The Thomist 87 (2023): 131-52

REMEMBERING GEORGE LINDBECK
AT THE CENTENARY OF HIS BIRTH
J. AUGUSTINE DI NOIA, O.P., S.T.MAG.
Adjunct Secretary, Dicastery for the Doctrine of the Faith
Vatican City

W

HEN I MOVED INTO St. Mary’s Priory in New
Haven in the fall of 1974 to begin graduate studies in
the department of religious studies at Yale University,
about ten years had passed since the conclusion of the Second
Vatican Council.1 George Lindbeck—the man with whom I was
to work on the theology of religions and interreligious
dialogue—had been among the delegated observers at the
council (1962-64), representing the World Lutheran Federation. He had already written a book about his experience and
the implications of the council for the future of Catholic
theology.2 He was fascinated by the fact that my time of formation in the Dominican Order had coincided with the years of
the council and its somewhat tumultuous immediate aftermath.
It was not until years later that I would become more
reflective about the impact of the council on the formation
communities of the Province of St. Joseph. At the time of my
conversations with Lindbeck, I recalled my formation years as
largely peaceful ones. Considering my experience in the light of
the fragmentation that he had seen elsewhere in the postconciliar Church, Lindbeck marveled at the comparative

1

An earlier version of this memoire was delivered at a Thomistic Institute conference
on postliberal theology on April 8, 2017 at the Dominican House of Studies in
Washington, D.C.
2
George Lindbeck, The Future of Roman Catholic Theology (Philadelphia: Fortress
Press,1970).
131

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J. AUGUSTINE DI NOIA, O.P.

tranquility of the situation I remembered and eventually he
found a way to interpret it for me.
Some of what I learned from him in those conversations I
later ventured to formulate in a lecture in 2009 on the occasion
of the dedication of the new academic wing and theological
library at the Dominican House of Studies in Washington, D.C.
Lindbeck had helped me to see the importance, for the
Dominicans, of
the relatively calm assimilation of the renewal measures promulgated by the
Second Vatican Council. This development was due, at least in part, to the
fact that during and after the years of the council the faculty and senior friars
in the DHS community and in the province construed the conciliar teachings
as being in essential continuity, rather than a disruption or break . . . with
previous Catholic teaching and the tradition.

As I acknowledged in that lecture:
Although there were difficulties, perhaps especially during the 1970s, the
council was generally not experienced as a revolution. Without the destructive
turmoil that had beset some other Catholic institutions and communities, the
fundamental patterns of the Dominican religious and liturgical life of the
priory, as well as those of formation and theological education in the
Thomistic tradition, while undergoing necessary adjustments, continued more
or less undisturbed.3

When I heard Pope Benedict XVI, in his momentous Christmas
discourse to the Curia on December 22, 2005, contrast the hermeneutic of discontinuity and rupture with the hermeneutic of
reform and continuity in the interpretation and implementation
of the Second Vatican Council, I naturally thought of Lindbeck
who had, over thirty years before, first introduced me to these
categories for understanding the postconciliar period.
I
What I had absorbed in my conversations with Lindbeck
about the impact of Vatican II on the eastern province of
3

J. A. Di Noia, O.P., “Discere et docere: The Identity and Mission of the Dominican
House of Studies in the Twenty-First Century,” The Thomist 73 (2009): 119.

REMEMBERING GEORGE LINDBECK

133

Dominican friars was just one element in his analysis of the state
of late-twentieth-century theology. For me—and probably for
others as well—the immense interpretive power of this analysis
only emerged gradually as I began to teach theology after
leaving Yale in 1980.
In his first-rate new guide to Lindbeck’s life and thought,
Shaun Brown notes that “coming out of his experience as an
observer at Vatican II,” Lindbeck’s “cautious optimism” about
the future of Roman Catholic theology was on display in the
book bearing that title in 1970.4 Five years later, however, his
essay “The Crisis of American Catholicism” marked a shift in
his thinking as he noted that, instead of the “great upsurge of
Christian vitality and faithfulness within the Roman Catholic
communion . . . the aftermath of Vatican II can be read as
disastrous.”5
During our conversations in the following decades, Lindbeck
framed his analysis of the fractious state of American theology
in terms of a perceptive account of the aftermath of the Second
Vatican Council. According to this analysis, although united in
their appeal to the authority of Vatican II, rival American
Catholic theological positions were divided by two opposed
readings of the nature of the conciliar response to modernity
and its implications for the theological agenda. According to
one reading, the council was understood to commend a strong
reaffirmation of Catholic Christian identity, taking the broadest
view of its historic traditions, yet open to the cultural and
religious pluralism characteristic of our times. But in the eyes of
an influential group of American theologians, such a reading
reversed the true priorities of the council. It was not restoration,
but modernization, dialogue, and social commitment that
Vatican II chiefly sought to cultivate in the contemporary
Church. To a large extent, the state of theology in the United

4
Shaun C. Brown, George Lindbeck: A Biographical and Theological Introduction
(Eugene, Ore.: Cascade Books 2022), 82.
5
George Lindbeck, “The Crisis in American Catholicism,” in John Deschner et al.,
eds., Our Common History As Christians: Essays in Honor of Albert C. Outler (New
York: Oxford University Press, 1975), 49.

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States (and elsewhere) reflected the predominance of the second
interpretation of the council.
As the conciliar documents reveal, both programs—ressourcement and aggiornamento, as they came to be called—were
addressed at the council. But which of them had priority? The
documents themselves did not provide an explicit answer to this
question. Lindbeck persuasively argued that if one gives priority
to ressourcement, then one will read the conciliar documents in
the light of the Constitutions on Divine Revelation and the
Church (Dei Verbum and Lumen Gentium). But if aggiornamento has priority, then the Constitution on the Church in the
Modern World (Gaudium et Spes) is seen as providing the
interpretative key for the rest of the documents. In an effort
aimed at what came to be called reaccentramento, the
Extraordinary Synod of 1985, under the leadership of Pope St.
John Paul II and then Cardinal Ratzinger, sought to resolve this
question by balancing tradition-mindedness with modernization. But it was a sign of the ascendancy of aggiornamento in
the American Catholic reception of the council that such
recentering efforts were routinely decried by some theologians
as retrogressive and anti-conciliar.
This disagreement about the nature of the council’s response
to modernity needed to be set within the context of broad
trends in twentieth-century theology. Throughout most of the
earlier part of the century, Catholic theologians saw the program of modernization (aggiornamento) as possessing an important but subordinate value in comparison with the program
of ressourcement. It is well known that ressourcement furnished
a powerful impetus for theological work in both Catholic and
Protestant circles throughout the first half of the twentieth
century, and even more so in the period between World War II
and the opening of Vatican II. The impulse arose not from
historical or antiquarian interests but from a determination to
reaffirm Catholic Christian identity by means of a creative
reappropriation of its principal formative sources. In part, and
especially in its late-nineteenth-century phase, ressourcement
involved the recovery of medieval and Scholastic sources. But

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gradually and more broadly, attention shifted to Scripture,
liturgy, and the Fathers of the Church.
It became increasingly clear as the century wore on that
modernization would be an important byproduct of ressourcement. The earlier recovery of medieval and Scholastic sources
had been so successful as to have restored and reinforced a
fundamentally post-Tridentine theological edifice, with at least
deference to—if not actual adoption and promotion of—the
positions of Aquinas as its cornerstone. This neo-Scholastic and
neo-Thomistic revival supplied the means to refute the errors of
modernity if not always to engage its challenge. But study of the
biblical, liturgical, and patristic sources afforded theologians
access to the immeasurably more pluralistic pre-Scholastic
period. In a strategic deployment of ressourcement, its practitioners sought to recover the greater tradition at the expense
of what they considered the narrower post-Tridentine tradition
enshrined by neo-Scholastic and neo-Thomistic theology. For
neo-Scholastic theologians, ressourcement had provided access
to an arsenal; for biblically and patristically oriented theologians, it seemed to unlock a treasure.
Thus it transpired that the later phase of the twentiethcentury ressourcement had a powerfully modernizing edge. It
cut into the neo-Scholastic hegemony through the radically
pluralizing introduction of biblically and patristically based
theological positions in dialogue with modern culture and philosophy. The passion at the core of the ressourcement program
stemmed, nonetheless, from a tradition-minded reaffirmation of
Catholic Christian identity. Ressourcement theologians shared
the confidence that the richness of the Christian tradition, once
displayed in all its wonderful diversity and breadth, could not
fail to win a favorable hearing in the modern world.
While this conception of the balance of ressourcement and
aggiornamento remained in place throughout the council, it did
not fare well in the postconciliar period. In the popular American reception of the results of the council, it never even had a
chance. Almost from the start, the program of aggiornamento
was seen by the public and the media as providing the key to
the conciliar deliberations and actions. Vatican II came rather

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quickly to be viewed as representing a sharp break with the
previous centuries and as charting a new course for the Church
as it entered the twenty-first century. In part, this reception was
fostered by the early implementation of the Constitution on the
Sacred Liturgy (Sacrosanctum Concilium). This document, in
addition to recommending the reform of the liturgy, was also
understood to signal a vast overhaul of Catholic life. Reform
and renewal were widely viewed as equivalent with modernization rather than with the reaffirmation of Christian identity
implicit in the ressourcement. Modernization came to entail in
practice a vigorous engagement in dialogue and in socially
transformative action.
With massive consequences for the future of Catholic
theology in the United States, the program of aggiornamento
prevailed in American Catholic reception of the council from
the outset. In theology, the priority of aggiornamento over
ressourcement entailed more than simply the updating of forms
of life and expression. It often meant a readiness to appropriate
the agenda of modernity, especially in correlationist and
revisionist modes of theological reflection. In correlationist
conceptions of the relation of faith and modern culture, culture
asks the questions to which faith provides the responses. In
revisionist conceptions, faith tailors its claims with an eye to
prevailing canons of reasonability and applicability. Both
theological styles in varying degrees embodied an accommodationist appropriation of the modern agenda that was not
favorable to the affirmation of traditional Christian claims
about revelation, the status of Scripture, the person of Jesus
Christ, and the meaning of human life.6 Even where correlationism and revisionism were not operative as explicit
methodological commitments, the priority of aggiornamento
fostered a climate in which modern criteria of rationality were
perceived to be in competition with fidelity to the Christian
doctrinal tradition.
6

For an analysis of religious accommodationism, see Peter Berger’s deeply influential
address, “A Sociological View of the Secularization of Christianity,” Journal for the
Scientific Study of Religion 6 (1967): 3-16.

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137

American Catholic theology increasingly came to display a
typically modern profile. The characteristic concerns of modern
theology, singly or in combination, gained prominence in
theology over the final decades of the twentieth century: the
primacy of the category of experience (whether religious or
common human experience); the subjective turn, with its emphasis on the structures of human existence as affording the
chief context for theological affirmation; the centrality of
theological anthropology; universalism in the doctrine of
revelation; pluralism in the attitude to other religions; insistence
on the historically conditioned nature of formulations of the
faith; the ascendancy of historical-critical approaches to the
study of Scripture; antipathy to doctrinal norms; the centrality
of critique and dissent with reference to the tradition and
magisterium; a preference for procedural over thematic ecumenism; in ethics, the centrality of obligation and the autonomous agent. In addition to these familiar characteristics of
modern theology, some American Catholic theology drew from
liberation theology an emphasis on political activism and the
notion that certain experiences, especially those of the oppressed, afford a privileged access to the meaning of revelation.
II
While Lindbeck helped me to understand mid-twentiethcentury Catholic theology in the light of postconciliar trends, it
was especially in listening to the lectures of his Yale colleague
Hans Frei on nineteenth-century Protestant thought that I began
to see the parallels between Protestant liberalism and Catholic
aggiornamento.
Frei’s The Eclipse of Biblical Narrative was published during
my first year in New Haven.7 This enormously important book
eventually led biblical scholars and theologians to question the
hegemony of historical-critical methodologies for mediating the
meaning of the Scriptures for theological, doctrinal, and other
7

Hans W. Frei, The Eclipse of Biblical Narrative (New Haven: Yale University Press,
1974).

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churchly uses. As Brown points out, Lindbeck attests to Frei’s
significant influence on his own understanding of biblical
hermeneutics.8 Frei was critical of the modern theory and
practice of biblical hermeneutics and persuasively underscored
the validity of precritical narrational and typological hermeneutics, which had read the Scriptures as a unified account of
revelation and salvation with Jesus Christ at the center.
Later it would be clear that Frei’s book had opened the way
for the recovery of a doctrinally and liturgically structured
reading of the Scriptures that is central to postliberal theology.
But more influential for me at the time were his lectures on
nineteenth-century philosophy and theology, and his seminars
on Karl Barth. Though I had learned something about them in
history of philosophy courses at our house of studies in St.
Stephen’s Priory (Dover, Massachusetts), I had never read
Kant’s Critique of Pure Reason and Religion within the Limits of
Reason Alone, or Hegel’s Phenomenology of Spirit and Lectures
on the Philosophy of Religion, or Schleiermacher’s On Religion:
Speeches to Cultured Despisers and The Christian Faith. Barth
had not figured significantly in my theological studies. But now
I read his Church Dogmatics and his study of nineteenth-century
Protestant thought.9 Frei’s lectures and his brilliant essay on
“Niebuhr’s Theological Background” were my guides.10 When I
chose the somewhat playful title for the earlier version of this
memoire in 2017—”Taking the Cure at Yale”—what I had in
mind chiefly was the intellectual epiphany I experienced when
reading nineteenth-century philosophy and theology under the
guidance of Frei and Lindbeck.
Like so many young Catholic theologians of my generation, I
had become a fledgling Rahnerian after braving the daunting
obscurities of transcendental philosophy to write my S.T.L.
thesis on Rahner’s theology of grace and the Trinity. For many
of them, and certainly for me, transcendental Thomism had
8

Brown, George Lindbeck, 121-22.
Karl Barth, Protestant Theology in the Nineteenth Century (Grand Rapids, Mich.:
Eerdmans, 2002).
10
Hans Frei, “Niebuhr’s Theological Background,” in Paul Ramsey, ed., Faith and
Ethics: The Theology of H. Richard Niebuhr (New York: Harper & Row, 1954), 9-64.
9

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swept into the vacuum created by the postconciliar eclipse of
classical Thomism.
But I now saw, as I wrote later in an essay on philosophical
theology, that
the 20th century transcendental turn in Catholic theology, associated
especially with the work of Karl Rahner, roughly parallels the 19th-century
turn to the subject in Protestant theology. The prevailing Rahnerian (if not
Rahner’s) theology in the Catholic community exhibits remarkable formal and
material similarities to modern Protestant theological positions.11

It became clear to me that there was another way and that there
were very good reasons not to think of Kant’s critique of metaphysics as a definitive block to robust Christian affirmation. But
more on this later.
More broadly, Lindbeck and Frei helped me to see that the
postconciliar Catholic experience in effect seemed to represent
a compressed and accelerated recap of nineteenth- and
twentieth-century Protestant experience. I found that study of
the range of Protestant responses to modernity would prove to
be instructive for understanding developments in Catholic
theology and in Catholic life generally in the aftermath of the
council.
The polarizing tensions that divided many Protestant
ecclesial communities into conservative and liberal branches at
the turn of the nineteenth century began to surface in the
postconciliar Catholic Church. In both the Protestant and the
Catholic contexts, issues turned on how to understand and
confront the challenge of modernity. In both Catholic and
Protestant circles in the United States, the conservative/liberal
split became more significant than denominational differences.
Progressive Catholics and liberal Protestants found themselves
allied against tradition-minded Catholics and evangelical Protestants. Evangelical Protestantism continued its rapid growth, in
comparison with a long-range decline in mainstream Protestant
11

J. A. Di Noia, "Philosophical Theology in the Perspective of Religious Diversity,"
Theological Studies 49 (1988): 410. See also my book, The Diversity of Religions
(Washington, D.C.: The Catholic University of America Press, 1992), 120-26.

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denominations. This trend confirmed the prediction that
Christian communities with a clear sense of their distinctive
identity vis-à-vis the wider culture possessed a competitive
advantage over those whose accommodationist strategies had
blurred their distinctively Christian profile.
The modernizing accommodationist strategies typical of
modern Protestant theology (and with them, the forms of
institutional adjustment they legitimated) were already showing
signs of exhaustion. One could predict that, over the long haul,
aggiornamento would not sustain a fully Catholic Christian
theology and a vital Church life. The agenda of modernization
by itself turned out to be an inadequate program for the
practice of Christian theology. Prevailing trends within the history of Christian thought suggested that ressourcement supplied
a more lastingly potent principle of theological energy. In fact,
within American Catholic theology, there was a growing movement that sought to reassert the priority of ressourcement over
aggiornamento in the appropriation of Vatican II and in the
theological enterprise generally. There was no question of
reversing the tremendous gains in flexibility, in collegiality, in
religious freedom, in social and political awareness, in commitments to dialogue with other Christians, other religious people,
and nonbelievers, in respect for diversity within the world
Church, and so on—all achieved in the name of aggiornamento.
Rather, there was a recovery of the astute insight that fueled the
work of the original ressourcement theologians: that an
uncompromising, unapologetic but open reaffirmation of the
fullness and richness of the Christian tradition is in itself a
powerful form of engagement with modernity.
In combination with wider cultural and intellectual trends,
these developments produced a favorable environment within
Protestant and Catholic theology in America for the emergence
of a complex set of approaches that would come to known as
postliberal theology.12 I was hooked.

12

For perspective, see James J. Buckley, “Postliberal Theology: A Catholic Reading,”
in Roger A. Badlam, ed., Introduction to Christian Theology (Louisville: Westminster

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III
Naturally, when I arrived in New Haven in 1974, I had
never heard of postliberal theology, and neither had anyone
else. It was only ten years later, in 1984, after the publication of
Lindbeck’s The Nature of Doctrine, that it entered common
discourse.13 The group of graduate students whom I found at
Yale in 1974 and those who later joined us there formed deep
bonds of intellectual and spiritual friendship that have endured
to this day. We didn’t have a name for it then, but we knew that
something quite remarkable was taking shape there and that we
were very fortunate to be among its early beneficiaries.
Forty years ago we probably would have called it the “Yale
School”—comprising not only theologians like Lindbeck, Frei,
and David Kelsey, but also the philosopher of religion William
Christian, the historian of doctrine Jaroslav Pelikan, and the
Scripture scholars Brevard Childs and Wayne Meeks, just to
mention the most prominent. Despite considerable differences
among them, these Yale professors—and others elsewhere who
shared their convictions—believed that new opportunities for
Christian affirmation were emerging as theology freed itself
from the strictures imposed by characteristically modern presuppositions. Not unlike ressourcement theologians in Catholic
circles, the postliberal theologians among these thinkers in
varying degrees turned to premodern and classical sources of
philosophy and theology—not in order to repristinate the past
as if the modern era had never occurred, but in order to make
these sources speak anew in the irreversibly pluralized
postmodern era.
Among several elements that could be cited, three imparted a
distinctively postliberal flavor to the new theological initiatives.
John Knox Press, 1998), 89-102; Bruce D. Marshall, “Aquinas as a Postliberal
Theologian,” The Thomist 53 (1989): 353-402.
13
In The Nature of Doctrine: Religion and Theology in a Postliberal Age, 25th
Anniversary edition (Louisville: John Knox Press, 2009), xxxiii, Lindbeck coined the
term “postliberal” to trace a path in the interpretation of religion and religious doctrines
that distances itself from modern developments without reverting to a “preliberal
orthodoxy,” and then devoted the final chapter to the shape of postliberal theology.

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In the first place, in the service of a broader conception of
rationality, Lindbeck and other postliberal theologians rejected
the modern (Cartesian) quest for a foundation for all knowledge, modeled on mathematical or scientific paradigms of
rationality. As a Thomist might say, reasonability and certainty
are analogous concepts, applicable to diverse domains of
knowledge in ways that are dependent on the principles
operative from one context to another. Scientific claims are
truth-bearing in ways that are distinctive from claims in other
fields like philosophy, ethics, religion, history, literary criticism,
and so on. In assessing claims to rationality and truth, it was
axiomatic for postliberal theologians to attend to the context in
which these claims are embedded. Truth and rationality are far
broader notions than modern thinkers were generally prepared
to acknowledge. In this connection and in sharp contrast to
modernity, postliberal theologians insisted on the centrality of
tradition and authority in legitimating and supporting truth and
rationality (not only in the religious but in the scientific and
philosophical fields as well).
Two other characteristic elements in postliberal theology
were the insistence on the role of texts and narratives in shaping
thought and culture, and its stress on the importance of
relationships and community in fostering intellectual and
personal identity. These emphases challenged rationalism and
positivism in modern philosophy of language and epistemology,
and individualism in modern moral and political philosophy. In
part the postliberal insistence on the culture- and identityshaping roles of language was the outcome of the so-called
“linguistic turn”—a series of developments in continental and
Anglo-American philosophy stemming from the thought of
Heidegger and Wittgenstein respectively.14 Postliberal theologians sought to secure the objectivity and realism of knowledge with reference, not to the inner workings of consciousness
(as in rationalism) or to their correspondence to objective facts

14

See Fergus Kerr, O.P., Theology after Wittgenstein (Oxford: Basil Blackwell,
1986).

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(as in positivism), but to a shared world of meaning and truth
embodied in the linguistic practices of a community.
IV
Traditionally, the Yale divinity faculty was known to
welcome confessional commitments in its graduate students.
Whether Anglican, Catholic, Lutheran, Reformed, or other,
these confessional backgrounds were regarded as the natural
seedbed of theology. In seminars Lindbeck would routinely invite students to speak to the issues under discussion out of their
distinctive doctrinal or theological traditions. You can imagine
my alarm when Lindbeck turned to me in a seminar to inquire
about what Aquinas had to say about the matter under
discussion. Thus it happened that another important aspect of
the “cure” I took in those six years in New Haven was to return
to the study of Aquinas so that I would be able reply to
Lindbeck intelligently.
Once I began teaching, my recovery of Aquinas began in
earnest. My teaching responsibilities included the first fortythree questions of the Prima pars of the Summa theologiae—
that is, the courses on the nature of theology, and on the
doctrine of God One and Three. Later they would extend to the
doctrine of creation and theological anthropology, and even,
occasionally, sacramental theology.
As my rediscovery of Aquinas reshaped my thought, I found
that my developing Thomism and newly formed postliberal
sympathies made for quite congenial partners. The characteristic postliberal determination to overcome the legacy of
modernity’s turn to the subject in epistemology and ethics
resonated with Thomistic metaphysics and the modest place
within it occupied by epistemology. Like postliberal theology,
Thomism rejects the modern equivalence of consciousness with
the true self, insisting instead on the fundamental importance of
bodiliness—and hence on the immersion of human beings in a
natural cosmic order and on patterns of activity in a community
of social and personal relations—as a constitutive element of
personal identity. In postliberal theology, thought, bodiliness,

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agency, and community replace subjectivity, consciousness, and
the autonomous self as fundamental anthropological categories.
Read straightforwardly—rather than in the modernizing
construal given him by transcendental Thomism—Aquinas
supports precisely this displacement of the Cartesian separations
of mind and matter, of spirit and body, of subject and object,
and of moral self and moral agent. As the years of teaching
unfolded, I found that my reading of Aquinas and my reading of
postliberal theologians were mutually enriching in ways that I
could not always specify. Looking back on those twenty years of
teaching at DHS, I can identify four areas in which characteristic elements of postliberal theology coalesced with my
understanding of Aquinas to produce a distinctive—and one
hopes not incoherent—style of theological affirmation.
Biblical hermeneutics was one of the first areas in which the
impact of postliberal thought was felt, particularly its insistence
on the interplay between the communal reading of texts and
their community-shaping power. Although it was generally
admitted that historical-critical approaches have much to
contribute to Christian understanding of the Bible, in the
practice of theology these approaches are logically subordinate
to the doctrinally and liturgically shaped reading of the Bible
precisely as Scripture.15 I saw that Aquinas’s understanding of
the appropriation of the results of other disciplines by sacra
doctrina in terms of the subalternation of sciences could be
enormously helpful in sorting out the complex logic of the
relation of historical and literary exegesis to theological hermeneutics. Directly relevant to a reading of Aquinas on these
issues was the fact that the movement from lectio to quaestio in
his own theological work represented the cresting of one of the
most potent movements of ressourcement in the history of
Christian thought.
Another area in which postliberal theology bore fruit in my
teaching was in my whole approach to systematic theology. If in
modern theology the basic question was, how can a modern
15

See David H. Kelsey, The Uses of Scripture in Recent Theology (Philadelphia:
Fortress Press, 1975).

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person believe this doctrine? then in postliberal theology the
basic question became, how can the deep intelligibility of this
doctrine be exhibited? From the outset, postliberal theology
avoided posing skeptical questions about the Christian scheme
of doctrine. There was a deep suspicion of the Cartesian
methodological starting point of doubt. The assumption was not
that religious claims inevitably challenge and bend accepted
canons of rationality. Rather, canons of rationality in the
religious realm have their own integrity and scope, and,
although they do not isolate the religious domain from other
domains, they nonetheless involve a distinctive logical structure.
Systematic theology in the postliberal vein begins by trying to
discern and exhibit this structure. The initial assumption is that
a doctrinal scheme and the religious pattern of life it commends
make good sense in theory and in practice. The task of
Christian theology is to explicate the inherent intelligibility of a
particular doctrine in connection with the whole body of
Christian doctrines. Again, Aquinas’s vision of the fundamental
and integral intelligibility of the mysteries of the Christian faith
is very attractive to postliberal theology. In his employment of
metaphysical and other conceptions in the service of this
explication, he was careful to avoid forcing the Christian
scheme onto a philosophical grid.
What is more, in postliberal theological approaches and in
marked contrast to those of modernity, Christianity’s particularistic claim to universality constitutes not an embarrassment
but a necessary feature of its commitment to and proclamation
of the truth about God’s dealings with us in Christ. The
postliberal emphasis on the narrational and communal sources
and embodiment of a community’s claim to truth renders the
Christian insistence on the uniqueness of Christ intelligible and,
incidentally, comparable to the particularistic claims of other
religious communities. Universal meaning is embedded in the
particularistically depicted and narrated story of the passion,
death, resurrection, and glory of Jesus of Nazareth, delivered to
us as Christ and Lord. The motto of von Balthasar’s theology is
pertinent here: “the greatest possible radiance in the world in
virtue of the closest possible following of Christ.” The

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replication of the pattern of Christ, in the imitatio Christi, is not
only the vehicle through which Christian personal and communal identity is shaped. It is also the particularistic medium in
which the universally applicable, though not universally
accessible apart from revelation and evangelization, truth of
Christ is made known to the whole world beyond the visible
ambit of the Christian community. The scandal of particularity
is no scandal for postliberal theology. Despite much wellintentioned defense of the interplay of history and metaphysics
in Aquinas, particularity is no scandal for his theology either. At
the center of his theology is a doctrine of salvation, embedded
in a Christologically shaped narrative. The objective of theological explication is to provide as complete as possible an
account of the principal characters upon whose agency the
movement and action depicted in the narrative depends: God,
angels, humans, and Christ. The narrative is not universalized
by the introduction of metaphysical concepts. Rather, its particularistic claim to universal relevance is secured by a web of
exegetical, theological, philosophical, and other patterns of
argumentation.
Finally, postliberal theology helped me to understand that
the interweaving of philosophical analysis and construction in
the web of theological argument in the Summa is in the service
of properly theological affirmation. The outcome is not a
theological/philosophical system, but a highly ramified complex
of interrelated dialectical arguments, always open to embracing
or engaging alternative positions that can be rationally justified.
The principle of unity and coherence is supplied by the
mysteries of the faith in their own interconnection and intelligibility, itself rooted in the scientia divina. The exigencies of
doctrinal and theological affirmation are seen to demand a
robust theological realism, and it is for this reason that wideranging appeals are made to philosophy and other nontheological disciplines. At each turn in the larger argument, such
appeals function as needed to secure the intelligibility of the
doctrine under consideration, whether it be the concept of
relation in the Trinity, or the concept of making in creation, or

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the concept of end in moral life, or the concept of disposition
(habitus) in grace and the virtues, and so on.
The Summa’s sparing methodological passages support this
reading of the role of philosophy in the explication of the
Christian faith. Though transposed to a new—a
“supernatural”—level of activity, ordinary patterns of human
perception, thought, and language are internal to knowledge
and talk about God in faith and, ultimately, in vision. According
to Aquinas, the life of grace involves not the infusion of a set of
capacities geared exclusively to engagement with God, but the
transformation and empowerment of natural capacities for
exercise at a new level. Hence, wherever relevant and appropriate, the results of nontheological inquiries as well as the logic
of assertion and argument can be brought to bear on the
theological explication of the contents of Christian faith. With
respect to its overarching formal interest, theology is thus a
field-encompassing field (Stephen Toulmin), and nontheological
disciplines contribute to its pursuit of understanding and
explication of divine revelation. Because of the prominence of
the role of philosophy here, these issues are usually considered
under the rubric “theology and philosophy.” But other
nontheological disciplines contribute to theological understanding and explication, notably literary criticism, history,
sociology, psychology, and the natural sciences.
The role of the philosophical component in Aquinas’s
theological arguments can be seen in Aquinas’s discussion of the
triune God in questions 2-43 of the Prima pars. That the
discussion of the existence and nature of God in questions 2-26
has a properly theological role to play is clear from Aquinas’s
prior description of the nature of theological inquiry (q. 1).
Asserting that theology gets its subject matter from revelation
entails that faith in God constitutes one of the principles of the
inquiry now getting underway. The triune God is already “in
place,” so to speak, in his full Christian characterization. The
burden of the argument in question 2, on the existence of God,
is to assert that the one confessed as Father, Son, and Holy
Spirit is the cause of the world. Through an interweaving of
philosophical and scriptural premises, the subsequent argument

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in questions 3-26 exhibits something of the kind of life the
triune God enjoys as cause of the world. The force of these
arguments is to secure the particularistic claim to universality
which the Christian community makes for its doctrines.
Philosophically shaped arguments concerning God’s existence function to secure this universal claim. Starting with
observable features of the world, such arguments affirm the
divine agency as the source of these features and of the world
order as a whole. Whatever their logical merits or probative
force, their position at the beginning of the theological inquiry
signals the logical space that Christians’ claims are understood
to occupy. This discussion functions to locate Christian worship, nurture, practice, and belief with respect to the widest
possible conceptual map. The triune God who is adored,
confessed, and proclaimed in the Christian community has not
only a local, narrative, or contextual reference within the usage
of a particular cultural and linguistic community. He is none
other than the cause of the world.
While developed in connection with scientific and
metaphysical claims, such arguments are subsumed in a properly
theological and scripturally based inquiry. They do not displace,
but rather presuppose the reading of Scripture as a “canonically
and narrationally unified and internally glossed . . . whole
centered on Jesus Christ, and telling the story of the dealings of
the Triune God with his people and his world in ways that are
typologically . . . applicable to the present.”16 In effect,
philosophical analysis and construction enable Aquinas to
address the question (here and in subsequent discussions of the
divine nature and agency, of angelic and human natures, and,
finally and decisively, of Jesus Christ as divine-human agent):
what must be true of the main characters of the Christian
narrative for it to have the features Christians claim for it, truth
and “followability”? Philosophy and other nontheological
disciplines contribute as needed to filling out these complex
characterizations. A literary analogy may help at this juncture.
16

George Lindbeck, The Church in a Postliberal Age, ed. James Buckley (Grand
Rapids, Mich.: Eerdmans, 2002), 203.

REMEMBERING GEORGE LINDBECK

149

In a critical study of Melville’s Moby Dick, for example, the
complex narrative need not be continually retold in the course
of literary analysis of the motivations and structure of the main
characters. In somewhat the same way in the Summa theologiae,
Aquinas presumes his readership’s detailed familiarity with the
Christian narrative in order to show—or, more accurately, to
remove obstacles to seeing—that its central claims are true and
its chief injunctions followable.
Aquinas thus provides a powerful model of theological
affirmation and realism over against alternatives that locate the
reference for Christian talk about God either in human experience of God or in the linguistic practices of the community.
The philosophical component in his discussion of the existence
and nature of the triune God serves purposes internal to this
properly theological project. In this discussion, the triune God is
not left behind but presupposed. The central affirmation of
questions 2-26 of the Prima pars is that the Father, Son, and
Holy Spirit are together one God, sharing the single divine life
of sheer existence (ipsum esse per se subsistens).
V
My conversations with Lindbeck continued after I moved on
to the Dominican House of Studies. Especially during the fall
semesters when I was teaching the nature and method of
theology, we often reprised the theme of ressourcement and
aggiornamento. We talked about the affinities between postliberal theology and the ressourcement agenda in Catholic
theology. Like ressourcement, postliberal theology favors
tradition-mindedness over traditionalism, on the one hand, and
revisionism and correlation, on the other. In contrast to the
program of aggiornamento, postliberal theology sees systematic
importance in the reaffirmation of Christian identity as a means
of promoting Christian fidelity and Christian proclamation.
When accorded primacy over ressourcement, aggiornamento
looks to postliberal eyes as if always on the verge of running out
of breath as the culture rushes several steps ahead. Conceived
simply as the updating of theology, aggiornamento is never

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J. AUGUSTINE DI NOIA, O.P.

finished catching up; conceived more grandly as modernization,
it is already far behind.
On the other hand, ressourcement theology has sometimes
shown itself unable or unwilling to confront and resolve the
conceptual problems—the quaestiones, as Aquinas might say—
that the sources themselves serve up. Lectio is not always
enough. Lindbeck and I talked about this often. We agreed that
Aquinas provides a set of strategies for the disciplined appropriation of the results of nontheological intellectual
inquiries—like philosophy, philosophical ethics, history, and
psychology—in order to advance the analysis and resolution of
such problems. The vastly pluralized postmodern contexts in
which theology is undertaken today accentuate the challenge.
Though sympathetic to the ressourcement agenda, postliberal
theology has never shared its unfortunate antipathy for
Thomism. The rigorous philosophical analysis and sound
patterns of argumentation fostered in the Thomistic tradition
are skills and habits of mind that are also much valued in
postliberal theology.
Lindbeck appreciated and imitated what he called the
“question approach” of Aquinas. In a 2007 interview, speaking
about the ecumenical purpose of The Nature of Doctrine, he
said:
[Like Aquinas] you raise a question, and then there is an objection to the
position that you’re going to take, and then you try to answer the objection. I
would say that what I’m trying to do in The Nature of Doctrine—to develop a
so-called rule theory of doctrine, a grammatical rule theory of doctrine—is an
attempt then to provide a supporting conceptuality for seeing how this
“question method” proceeds and how apparently contradictory views can be
shown not to contradict each other [if one introduces] the appropriate
distinction.17

For this “Yale School” approach that influenced my own
teaching, I owe a considerable debt of gratitude to Lindbeck and
Frei. Frei we lost early and very suddenly in 1988. Lindbeck we

17

John Wright, ed., Postliberal Theology and the Catholic Church (Grand Rapids,
Mich.: Baker Academic, 2012), 72.

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151

lost in 2018, five years short of his hundredth birthday (March
10, 1923) in Luoyang, China.
As we honor the centenary of Lindbeck’s birth, both
theologians familiar with his work and new students will
welcome Shaun Brown’s splendid introduction to his life and
thought. Brown’s seven chapters consider in turn Lindbeck as a
Lutheran, a student, a medievalist, an observer at Vatican II, an
ecumenist, a postliberal, and an Israelologist. I am not aware of
any comparable overview of Lindbeck’s major books and essays.
Brown joins clear exposition with judicious commentary to
produce an extraordinarily useful companion to Lindbeck’s
theology. Here I have tried to convey something of the gradual
way I came in varying degrees to absorb Lindbeck’s thought
over the course of years of studying and teaching theology, and
applying it to the challenges of the global Catholic community.
Readers of The Thomist will have grasped that Lindbeck’s
theology constitutes more than anything else an approach to
theological construction that, as John Webster put it, “has
sought to revisit Christian doctrine, asking not so much what
might be wrong with it but what resources it may contain to
redefine or illuminate current perplexities.”18
When he visited the Dominican House of Studies, Lindbeck
loved to participate in the Eucharist and the Liturgy of the
Hours in the chapel. He especially loved chanting the Psalms. I
remember once, after Midday Prayer, he turned to me while we
were still sitting in the choir stalls and said, “You know, Joe, I
think I could have been a Dominican.” That was over forty
years ago. In the 2007 interview quoted above, when asked if
his work was a preparation for the future, Lindbeck replied:
The one advantage of living a long time is that one mistrusts entirely
predictions of what the future will bring. . . . At any rate, given the revolutions
that are likely to be taken and the way we find ourselves reacting to reality, I
can’t help but think that there is at least a good chance that the sorts of things
that drove the church to what we call neo-orthodoxy that required a sizable

18

John Webster and George Schner, S.J., eds. Theology after Liberalism (Oxford:
Blackwell, 2000), 55.

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J. AUGUSTINE DI NOIA, O.P.

interest in the visible unity of the churches, is something we won’t escape in
this century either. That’s the way I look at the future. Therefore, I think of
what I have been doing all my life in working for the visible unity of the
church . . . might very well be very valuable in the things that will be
happening in the not very distant future. So I am quite willing to leave this
life, and quite optimistic about my life’s work.19

19

Wright, Postliberal Theology and the Catholic Church, 73-75.

BOOK REVIEWS
Thomas Aquinas and Contemplation. By RIK VAN NIEUWENHOVE. Oxford:
Oxford University Press, 2021. Pp. ix + 220. $85.00 (cloth). ISBN:
978-0-19-289529-5.
A medievalist and systematician already known for his scholarship on
Flemish mysticism, Rik Van Nieuwenhove has brought together a series of
eight philosophical and theological essays on contemplation in Aquinas that
make for highly stimulating reading. The resulting collection takes ongoing
intra-Thomist debates further in important ways, and also opens up new
interpretative as well as speculative questions on fascinating themes such as
the seven gifts of the Spirit or the ways in which grace can (and cannot)
stretch the human being’s cognitive capacities before the divine mystery. The
author sets a difficult task for himself, as he tackles a wide range of issues
closely linked to the theme of contemplation, such as the metaphysics of the
transcendentals, the relation of philosophy and theology, and the limits of
discursive knowledge in the higher types of graced contemplation. The choice
of this breadth of topics enables the pursuit of a panoramic approach to
Aquinas’s thought, a breadth that hardly excludes in-depth analysis of several
key texts in Aquinas’s vast corpus. One of the book’s many strengths is surely
its fresh engagement in the well-trodden territory of question 180 of the
Secunda secundae and similar texts. One of its weaknesses is a lack of engagement with recent Aquinas scholarship on some of the more crucial issues
raised. The ultimate aim of the book is not so much to present an exhaustive
account of the nature of contemplation in Aquinas’s thought as to offer a rich
sketch that invites completion.
After (1) a substantial introduction that forms the book’s opening chapter,
the reader is treated to seven beautiful essays that treat the following themes:
(2) some key epistemological issues such as the intellect’s three acts
(apprehension, judgment, reasoning), the role of phantasms in human understanding, and the nature of the mind’s simple gaze; (3) the contemplation of
the transcendentals; (4) thirteenth-century mendicant debates on the active
and contemplative life; (5) the relation between faith, theology, and
contemplation; (6) the link between charity and contemplation; (7) the role of
the Spirit’s seven gifts in contemplation; and finally, (8) happiness and the
beatific vision.

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The introduction may exaggerate somewhat the extent to which scholars of
Aquinas have neglected the theme of contemplation in recent decades. The
book does not mention the ground-breaking study by Cruz-Gonzalez Ayesta
on the gift of wisdom in Aquinas, nor Daria Spezzano’s magnificent work on
divinization and wisdom. The fifth chapter does not mention the recent historical monographs on sacra doctrina in Aquinas by francophone scholars such
as Henry Donneaud and Adriano Oliva (though the author does mention
some of Oliva’s other articles). As I will argue below, a deeper engagement
with these and other voices would have helped the author to avoid some
interpretive missteps. Van Nieuwenhove’s preferred interlocutors include
Bernard McGinn and Simon Tugwell (though he ultimately transcends the
limits of the latter’s problematic reading of contemplation in Aquinas, done in
complete abstraction from the theology of the seven gifts). Setting these
difficulties aside, we should note that the introductory (first) chapter nicely
anticipates chapter 5, as the author clearly and ably situates Aquinas’s
approach to theological contemplation in relation to philosophical and beatific
contemplation. Along the way, he convincingly compares and contrasts Aquinas’s way to the more charismatic style of Bonaventure’s theology (though one
does wonder if Aquinas’s understanding of the ideal theologian as a studious
man of prayer radically open to the Spirit’s movement in the seven gifts and
charisms is somewhat obscured).
The book’s second chapter sets forth some of its more controversial claims.
The author helpfully reads Thomas in contrast to Bonaventure on the relation
between certain knowledge and human access to the divine ideas. He then
interprets Aquinas’s vision of the mind’s three basic operations in light of his
angelology. The presentation of Aquinas’s noetics is both accessible to beginners and rich in analytical detail. I do find the author’s hypothesis of a fourth
act of the intellect (as intuitive understanding) perplexing: nothing in
Aquinas’s general epistemology (as articulated in questions 75-89 of the Prima
pars and in his commentaries on Aristotle) seems to support this theory of a
fourth noetic act distinct from judgment (or second act), and the author
himself seemed to step away from this hypothesis in a Thomistic Institute
podcast published in 2021. Why would Aquinas invent a new act of the mind
at question 180 of the Secunda secundae, but say nothing about it elsewhere?
And why would he categorize the Spirit’s gift of wisdom as an act of
judgment, instead of presenting it as an instance of a fourth act? Finally, given
these textual lacunae, how would such a theory fit with the pedagogical aim
that Aquinas set for himself (and executed so well) in the Summa theologiae?
Since at least the seventeenth century, Thomists have faced the temptation
of locating in Aquinas something close to the kind of intuitive mystical
knowledge that some of the major early modern schools of spirituality
propose. The Thomists who have given in to this temptation (e.g., Réginald
Garrigou-Lagrange) thereby risk over-Platonizing Aquinas. However, like his
teacher Albertus Magnus, Aquinas steered a deliberate course away from some
of the more adventuresome readers of Dionysius the Areopagite (e.g., Thomas

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Gallus, who would indirectly influence Carthusian, Franciscan, and Carmelite
authors in important ways). Aquinas minimized the distance between natural
and supernatural modes of knowing God (for all that is known is known in
the mode of the receiver), all the while maintaining a clear distinction between
them (for grace truly elevates nature), as he made theoretical space for a
certain kind of supernatural intuitive cognition (especially by the four noetic
gifts within the seven gifts of the Spirit) that retains a deep continuity with
other kinds of knowing. In other words, Aquinas gently yet very consistently
corrects Dionysian (and medieval Dionysian) epistemologies that seem to
underestimate the place of acquired knowledge in supernatural cognition (as a
close reading of Aquinas’s much-neglected De Divinis nominibus shows), and
it is crucial for his readers to trace this move so as to grasp his fundamental
doctrinal intentions in his theology of contemplation. Van Nieuwenhove’s
hypothesis of a fourth act of the intellect seems to push Aquinas further
toward Neoplatonism than he himself was willing to go.
To be clear, the author largely succeeds in his overall endeavor: the fourth
act remains a hypothesis, and much of the panoramic sketch laid out in this
book succeeds well without that hypothesis. The third chapter draws a neat
contrast between medieval Franciscan approaches to the transcendentals and
Aquinas’s path. The latter distinguishes more firmly between philosophy and
theology, and also defends the legitimate autonomy of the former, all the
while showing how philosophical contemplation also disposes for the
theological kind.
Chapter 4 gives the work a more historical flavor as Aquinas’s theory of
contemplation is set against the backdrop of the fierce mendicant controversies that unfolded in mid-thirteenth-century Paris, which very much
turned on the nature of the active and contemplative lives and their place in
the life of the Church. Here, the author not only draws good fruit from JeanPierre Torrell’s historical analyses of Aquinas’s writings on the religious life,
but also engages critically with an almost-forgotten gem, namely, Hans Urs
von Balthasar’s 1954 commentary on the Summa questions covering the
charisms and contemplation. This fourth chapter displays the author’s
considerably synthetic power, as he demonstrates the patristic (Gregorian)
roots of Aquinas’s theology of contemplation as well as its link to his doctrine
of the episcopate, yet without obscuring the undeniable and strong Aristotelian framework.
Chapter 5 competently traces an important development in Aquinas’s
notion of faith from his early to his later writings, which helps the author to
articulate the significance of Aquinas’s way of appropriating the theme of
subalternation in his theory of sacra doctrina (101-6). We then find a wonderfully creative illustration of the grasp of first principles as the author draws
an analogy between the principles of sacred doctrine and the way in which we
engage with art and literature (107-8). Further on, the author traces Aquinas’s
distinction between knowing and believing perhaps almost to the point of
separation, such that his explanation of how rational argumentation functions

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in Aquinas’s theological texts becomes somewhat muddled (117-23). At this
point, the decision not to engage in an extensive way with some of the vast
Thomistic literature on topics such as the role of philosophy within
theological argumentation shows its disadvantage.
Chapter 6 centers on a refutation of Jean-Pierre Torrell’s explanation of
how Aquinas distinguishes between philosophical and theological contemplation (though no specific reference to Torrell is given in the notes). The
chapter’s strong points emerge in the author’s exposition of love of God and
love of self, and its convincing rehabilitation of philosophical contemplation
as a good in its own right. Strangely, the sixth chapter’s last section covers the
imago Dei in three pages, a theme that seems ripe for more extensive use in a
study on contemplation, and most helpful to gain a fuller grasp of how
Aquinas relates the contemplative and active life (one thinks especially of his
integration of John Damascene’s theology in question 93 of the Prima pars).
The author likely intended chapters 2, 5, 6, and 7 to stand as the pillars of
his work. If this reading is fair, then the seventh chapter brings this book to its
climax, in a study of the Spirit’s gifts, prayer and wisdom. I have already noted
the absence of some key interlocutors on this theme. The author first rightly
identifies an important limitation in Garrigou-Lagrange’s modern classic,
Christian Perfection and Contemplation, where the famous Angelicum
professor reads Aquinas partly with Carmelite eyeglasses (and, we might add,
vice versa) (147). One does wish that Van Nieuwenhove had engaged with the
brilliant French mystical theologian more extensively in this book, despite the
latter’s problematic hermeneutic. In this chapter, Tugwell very much becomes
the author’s main inspiration, though not exclusively so. He demonstrates well
Aquinas’s distinction between prayer (i.e., intercessory prayer) and the
contemplative act (148-54). The originality of Aquinas’s approach to the
Spirit’s seven gifts comes to the fore thanks to a solid comparison and contrast
with Bonaventure and Albert (156-68). Unlike Garrigou-Lagrange, the author
reads the Summa’s teaching on the seven gifts on its own terms, in abstraction
from the less-developed and earlier theology of the Sentences commentary.
Yet surprisingly, he makes the same move as Garrigou-Lagrange when he
misreads the Son’s invisible mission (STh I, q. 43) as a description of the
Spirit’s gift of wisdom (172). In fact, the former is linked with any new gift of
sanctifying grace, while the actualization of the latter does not bear this
essential link to a new sanctification. The author rightly distinguishes the
ultimate fruit of the Spirit’s noetic gifts (such as understanding and wisdom) as
a simple knowledge or cognitive repose, yet perhaps also separates the
working of the Spirit’s gifts from that of discursive reasoning in ways that
Aquinas does not (169-74). Here too, one is reminded of Garrigou-Lagrange’s
reading of Aquinas (and of John of St. Thomas). Why can gifts such as
knowledge or wisdom not assist, perfect and crown such acts of reasoning?
Here, a closer analysis of Aquinas’s texts on the gift of understanding would
have helped (STh II-II, q. 8 is covered in less than a page) (169).

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Chapter 8 places Aquinas’s vision of happiness in relation to Albert and
Bonaventure. Here, the intellectual tensions between Aquinas and his teacher
quickly come to the fore. It is hard to do justice to such a broad and
controversial topic in one chapter, especially in a comparison of three major
thinkers, but the author provides a stimulating survey of the key issues in play
and a solid overview of Aquinas’s stance on beatitude.
Overall, Van Nieuwenhove renders medievalists and scholars of Aquinas an
invaluable service in several ways. First, he judiciously selects the kinds of
texts in Aquinas that we need to bring into an analysis of his theology of
contemplation. Second, he sets out the kind of questions that we need to pose
of these texts as we work toward a panoramic vision of Aquinas’s thought on
contemplation. Third, he makes a strong argument for the presence of a
particular kind of simple intuition in Aquinas (even if one might dispute some
of the details in his description thereof). Fourth, he helpfully avoids
speculative forays into theories of metaconceptual contemplation in an effort
to explain Aquinas’s notion of the contemplative summit in this life (unlike
readers such as Jacques Maritain). That is, the author’s arguments on behalf of
intuitive knowledge in Aquinas remain cautious and close to the primary text.
Fifth, the work is remarkably accessible, given the many technical nuances
involved with many of the subthemes, not to mention the breadth of topics
treated. For these and many other reasons, Van Nieuwenhove’s monograph
should restart and move forward important debates among philosophers,
dogmaticians, moralists, historians, and scholars of spirituality on medieval
and Thomistic theories of contemplation.
BERNHARD BLANKENHORN, O.P.
University of Fribourg
Fribourg, Switzerland

Salvation through Temptation: Maximus the Confessor and Thomas Aquinas
on Christ’s Victory over the Devil. By BENJAMIN E. HEIDGERKEN.
Foreword by PAUL M. BLOWERS. Washington, D.C.: The Catholic
University of America Press, 2021. Pp. xiv + 316. $75.00 (hardcover).
ISBN: 978-0-8132-3412-0.
Benjamin Heidgerken’s first monograph draws attention to the dense
cosmology of the premodern world. The universe consists of parts both visible
and invisible. The invisible world may not be susceptible to inquiry vis-à-vis
the physical sciences. Nevertheless, the invisible world is the subject of intense
scrutiny by early and medieval Christian authors. Even the demons, who are
invisible but by no means imperceptible, behave according to a certain logic.

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Locating Maximus and Aquinas within this “thicker universe” is a reminder to
theologians who, rather than wrestling within these premodern conditions,
pass over the talk of angels and demons as superfluous. If theologians do not
take this material seriously, then they disqualify themselves from shaping
theological imaginations by refusing to use their own. We need not be
surprised why the worse, and not the better, occupies this void.
Heidgerken offers a constructive contribution to fill this gap with his present work, which is a revision of his doctoral dissertation. His research falls in
line with one recent study of Maximus (though absent from his bibliography),
John Gavin’s They Are Like the Angels in the Heavens: Angelology and
Anthropology in the Thought of Maximus the Confessor (Rome: Institutum
patristicum Augustinianum, 2009). For Gavin, angels serve as a foil to clarify
Maximus’s theological anthropology. In a similar way, Heidgerken uses demonology to elucidate Maximus’s soteriology. Heidgerken argues that
demonic temptation resolves issues in scholarly treatments of Maximus. Christ
“is like us in all things save sin” (Heb 4:15). Yet, in his mature description of
Christ’s human will, Maximus claims Christ lacks a “gnomic will,” that is, a
deliberating function between alternatives, resulting from and conditioned by
human fallenness. The author proposes that demonic temptation—an
externalized, personified force—allows Christ to experience temptation’s
bites. This view avoids positing imperfections within Christ’s psyche, while
reverencing the fullness of human experience. One would be satisfied with a
complete inventory of the Confessor’s demonology in relation to his Christology. Yet, Heidgerken’s book goes beyond the seventh century to compare
Maximus with Thomas Aquinas. In his Introduction, Heidgerken inserts
himself among Marcus Plested, Matthew Briel, and Christiaan Kappes, who
have explored the intellectual exchange between Greek and Latin thinkers in
the medieval period and have revised in important ways the hackneyed labels
of “Eastern” and “Western” through their assiduous historical studies. Heidgerken follows the work of Antoine Levy’s Le créé et l’incréé, which compares
Maximus and Aquinas in order to arbitrate the Palamite controversy. This
comparative approach is not without pitfalls. Both figures are saturated with
secondary literature and any influence of Maximus on Aquinas is heavily
mediated—as Heidgerken is aware—through Aquinas’s medieval precursors
John of Damascus, Peter Lombard, and Alexander of Hales.
Chapter 1 treats Maximus’s sources for his anthropology and Christology.
Heidgerken identifies fourth-century bishop Nemesius of Emesa’s On Human
Nature as a key influence on Maximus’s development of the will and the role
of choice. I will say more on this later. He turns to Gregory of Nyssa’s On the
Soul and Resurrection, where Nyssa posits that affective behavior is natural to
the human condition, and choice results from human sinfulness. Heidgerken
then outlines Origen’s and Evagrius’s teachings on demonic temptation. He
shifts to Gregory of Nyssa and Gregory of Nazianzus to sketch the
Christological picture Maximus inherits, pointing out the different ways they
describe Christ’s relationship to unfallen and fallen human existence.

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Chapter 2 discusses Maximus’s anthropology with special reference to
human temptation. Heidgerken describes Adam’s original state as good,
containing the logos of immutability. However, Adam’s tropos or manner of
being was susceptible to motion and therefore change and corruption.
Heidgerken focuses on Satan’s role in the Fall in line with his overarching
argument. He draws attention to Quaestiones ad Thalassium 62, where
Maximus explains that Adam’s sinfulness constructs a home for the devil to
dwell in and continue his attacks. Heidgerken maps out the progression of the
moral act described by Maximus in Opusculum 1. He then explains
Maximus’s discussion of willful and unwillful temptation in Quaestiones ad
Thalassium 58, a theme found elsewhere in the Confessor’s works, most
notably in the Commentary on the Our Father. Maximus advises that
Christians should pray to be led away from the vicious temptations (willful)
and accept gladly the trials that assail us from the outside as an ascetic exercise
(unwillful). Heidgerken then discusses Christ’s subversion of demonic
temptation in Quaestiones ad Thalassium 21 to show how temptation and
soteriology function in Maximus’s vision of the ascetic life.
Chapter 3 evaluates Maximus’s account of Christ’s temptation. In Opusculum 1, Maximus distinguishes between essential and relational appropriation: what belongs to Christ’s human nature as such, and what Christ’s
human nature encounters but does not contain. For Heidgerken, the key
frontier is human choice. Maximus denies the presence of choice in Christ in
his mature anti-Monothelite works. Yet, building on Nemesius, Heidgerken
maintains that choice belongs essentially to the logos of human nature and
human rationality. According to Heidgerken, the lack of choice in Christ
would preclude the assumption of a full humanity. Heidgerken points to texts
where Maximus discusses that the salvific activity of Christ offers “stabilizing
choice” for humanity and allows for “choice without passion.” Maximus
points out, most notably in Quaestiones ad Thalassium 21, that Christ accepts
human passibility, such as physical weakness. Christ likewise disposes himself
to vulnerability, as identified by his temptation in the desert. According to
Heidgerken, Maximus teaches that Christ’s experience subverts the devil who
exerts a vicious grasp on free choice and human passibility. Heidgerken sees
the demonological aspect of Christ’s soteriology as essential for Maximus’s
dyothelite position. If, for Maximus, the natural will cannot resist the divine,
then the problem must be located elsewhere. For Heidgerken, this role is
played by demonic temptation, which diverts the natural will from its divine
object. As Heidgerken asserts quite clearly: “If the natural will itself is what
separates one from the divine, the Monothelites would be right to reject its
presence in Christ” (124).
The rest of the book follows the same pattern to explore Thomas Aquinas.
Chapter 4 discusses Aquinas’s sources, naming Burgundio of Pisa’s Latin
translation of John of Damascus’s On the Orthodox Faith, which re-presents
in large part Maximus’s account of the will. Heidgerken discerns several key
differences from Maximus that John of Damascus will transmit to later

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medieval authors, namely, the ambivalence of the natural will to God and the
denial of choice in Christ. He also credits Burgundio’s translation with
changing temptation’s origin from a demonic source, “τοῦ διαβόλου
προσβολῆς,” to a more impersonal “immissio perniciosi.” He then evaluates
Augustine of Hippo and Gregory the Great as patristic precedents for Aquinas,
concluding that both develop a Latin tradition that denies the interior
temptation of Christ. He ends the chapter with discussion of Peter Lombard
and Alexander of Hales; he importantly suggests that they attribute to human
concupiscence, or the “fomes peccati,” the origin for temptation, supplanting
demonic suggestion.
Chapter 5 details Aquinas’s anthropology in reference to human temptation. According to Heidgerken, Aquinas holds that temptation in the flesh is
strictly speaking a postlapsarian phenomenon brought about by Adam’s sin.
Prior to the fall, temptation was external and morally educative; temptation
was the means God used to lead Adam and Eve from grace to glory.
According to Heidgerken, Aquinas limits the role temptation—both concupiscence from within and demonic suggestion from without—can play morally
to educate the fallen human being. Temptations play primarily a punitive role.
Heidgerken contrasts this with Maximus, who considers all forms of temptation, internal and external, as arising from the demonic and therefore as
potential instruments for salvation in the hands of Christ in conjunction with
the willing ascetic.
Chapter 6 develops Aquinas’s account of Christ’s temptation by the devil.
Heidgerken sees Aquinas in contrast with earlier medieval writers, who tended
to minimize Christ’s association with temptations associated with fallenness.
Aquinas holds that Christ is subject to human vulnerability, such as hunger
and thirst. Christ is also subject to being transported by the devil while being
tempted in the desert. Aquinas denies any concupiscent element or internal
demonic stirrings in Christ, which he argues is unnecessary for Christ’s
satisfaction for sin. Further, concupiscence in Christ frustrates his “status as a
comprehensor who shares proleptically in the glorified condition of
humankind” (283). In other words, a concupiscent Christ cannot offer us the
ideal of a heavenly humanity.
A few issues should be noted. First, Heidgerken’s claim that Nemesius is
“undoubtedly the central source” for Maximus’s psychology is assumed rather
than investigated (22). Maximus is the first correctly to attribute the work to
Nemesius instead of Gregory of Nyssa and citations of Nemesius can be found
throughout Maximus’s writings. However, these citations almost invariably
appear as block quotes. Maximus clearly cited Nemesius. It is less clear that he
digested Nemesius and incorporated him into his thinking. This is evidenced
by his later denial of the gnomic will in Christ. For Nemesius, the human
moral act requires deliberation. Maximus contends that such deliberation is an
element of fallenness. Heidgerken argues that Maximus uses language of
“immutability of choice” or “choice without passion” resulting from Christ’s
assumption of human flesh (Opusculum 1 [PG 91:29C-32A]). In both these

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instances, these are attributes offered to humanity, not necessarily originating
in Christ himself. Further, this modification of choice does not entail a blind
acceptance of Nemesius. At least, it appears that Maximus amends the
Nemesian position, and, at most, he disagrees with him. In the same Opusculum that Heidgerken cites, Maximus asserts that “the humanity of God was
not moved according to choice” (PG 91:32A). He gives an important reason.
The faculty of choice distorts Christ’s humanity in a Nestorian fashion,
rendering his human nature into “a bare human being” capable of potentially
choosing against the will of God (cf. PG 91:29B). If the devil can prey on
human choice without possessing it, then Christ can heal human choice and
stabilize it in a deified human in the same way.
Second, one of Heidgerken’s more central points of comparison between
Maximus and Aquinas is their account of affective virtue. He argues that
“Maximus holds a non-eschatological conception of affective virtue that is
extrinsic and historically realized.” (89) For Aquinas, the perfection of
affective virtue for humans is only realizable eschatologically, that is, not
within historical time. Heidgerken asserts that Maximus remains “apophatic”
in his discussion of the affective life in the eschaton (95-96). This is not
entirely accurate. Maximus has a sophisticated understanding of the
transformation of vicious passions into virtuous emotions, each with their
place in divine life. Vicious fear is transmuted to awe before the throne of
God (Quaestiones ad Thalassium 10), and vicious grief is transformed to
participation in God’s grief for those not yet saved (Questions and Doubts
129). Maximus describes eschatological rest, “the Sabbath of Sabbaths,” as an
“erotic ecstasy” for God alone (Two Hundred Chapters on Theology 1.39).
Hence, Maximus is replete with cataphatic language regarding eschatological,
perfected affective virtue beyond the historical time.
Heidgerken should be commended for his ambitious reading of two of the
most important figures in the Christian tradition, East and West. One can
learn much from the history Heidgerken traces, even if at some points I disagree. The labels “East” and “West” in reference to theology have rightly been
problematized, for they can obscure where they should clarify. To go beyond
these paradigms, one must go deep before going broad. “The devil is in the
details,” the adage goes, and the devil rarely fixes problems; he only makes
new ones.
ANDREW J. SUMMERSON
Sheptytsky Institute of Eastern Christian Studies
Toronto, Ontario, Canada

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The Same God Who Works All Things: Inseparable Operations in Trinitarian
Theology. By ADONIS VIDU. Grand Rapids, Mich.: Eerdmans, 2021.
Pp. xix + 352. $50.00 (hardcover). ISBN: 978-0-8028-7443-6.
Adonis Vidu’s The Same God Who Works All Things: Inseparable
Operations in Trinitarian Theology defends the principle of the “hard
inseparability” of the operations of the three divine persons (xv). That is, in
any action performed by God in the created order by way of efficient
causality, all three divine persons act together inseparably. If this were not the
case, then not all three persons would be fully divine, because God would act
in the world without one or two of the persons acting. Vidu develops this
theme through nine chapters, building on or critiquing the Fathers of the
Church, conciliar teachings, Thomas Aquinas, and modern authors. Since it is
more recent authors who abandon the principle of hard inseparability, they in
particular will be subject to critique.
Vidu observes that the principle of hard inseparability is suggested by the
Scriptures (xiv), and in his first chapter he pursues “a biblical theology of
inseparable operations” (1) in five steps. After a word on Jewish monotheism
(1-11), he shows that Scripture identifies Jesus and the Spirit with the God of
Israel (11-23) and equates Jesus with the creator (23-31). He then considers
the inseparability of Christ and the Spirit (31-36) and examines the works of
the Trinity in the Gospel of John (36-49). Vidu argues, especially from the
Pauline corpus, that Christ and the Holy Spirit are God, and that therefore
they must have one same agency as God, with the Father and with each other.
For instance, he notes that both Christ and the Holy Spirit are recognized as
the YHWH of the OT who has returned to his people—a compelling insight
(16). The fact that Christ and the Spirit do divine things, such as forgive sins,
shows that they have divine being and must therefore act inseparably (19). For
Vidu, the strongest possible biblical support for the principle of inseparability
is the identification of Christ with the creator, since the act of creation cannot
be delegated to a creature; Christ must then simply be YHWH (23). Regarding
the inseparability of Christ and the Spirit, Christ works through the Spirit; he
is empowered by the Spirit and then gives the Spirit to us (35). In the Gospel
of John, Christ is not speaking of mere delegation when he says in 5:19 that
he does whatever the Father does (37).
In chapter 2, Vidu ponders the rise and decline of the idea of inseparable
operations in four sections on the Fathers (53-63), Augustine and Aquinas (6374), Christ’s two wills and two operations (74-82), and contemporary
theology (82-89). Vidu documents the defense of the principle of inseparability by Athanasius and the Cappadocian Fathers in their responses to
heresies. He then turns to Augustine’s and Aquinas’s accounts of appropriation and the divine missions for assistance in articulating the harmony
between personal distinction and inseparable unity. In appropriation, we
attribute something that is common to all three persons to just one distinct
person, based on a real affinity between that common attribute and a property

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of that person; for instance, we appropriate wisdom (which describes all three
persons) to the Son, since he alone proceeds (from the Father) by way of
knowledge (71). In the missions of the Son and the Spirit we have all three
persons producing a created effect that signifies only one distinct person,
because only one person is the exemplar of that effect. For instance, since the
Son alone proceeds by way of knowledge, the gift of wisdom that comes with
grace signifies the Son alone (72-73). With respect to Christ’s two wills and
two operations, Vidu argues that the Trinitarian principle of inseparability
helped resolve the question of the number of wills and operations in Christ,
because the number of wills and operations is determined by the number of
natures, not the number of persons (75). In early Christological debates, all
parties accepted the Trinitarian principle of inseparability (78). It is possible
for only the Son to be united to a human nature, because while the Father,
Son, and Holy Spirit act as one in the created order, they each act according
to their distinct personal mode (78). Finally, Vidu reviews more recent
authors like Karl Rahner, Colin Gunton, and Catherine LaCugna, who are
concerned that the principle of hard inseparability blurs real personal
distinction, results in the reduction of the divine person to a relation, and
cannot adequately account for the distinct missions of the Incarnation and the
indwelling of the Holy Spirit (88). However, abrogating this principle risks
cutting ourselves off from Scripture and conciliar teaching (82 n. 82, 90).
Chapter 3 probes unity and distinction in divine action, in three parts:
triune causality (92-106), the knowledge of the divine persons and their
actions ad extra (106-16), and social Trinitarianism (116-22). Regarding
triune causality, actions in the created order cannot be the basis of distinction
within God, otherwise God would be dependent on creatures (93). A key
principle here is equiprimordiality—namely, that perfect unity of essence and
real distinction of persons must both be asserted at the same time; neither can
be subordinated to the other (97). Vidu refreshingly observes that “the
impression that the East emphasizes the persons while the West stresses the
essence is caricatural” (ibid.) and that there is no monarchy of the Father in
the thought of the Fathers but rather a monarchy of all three persons (98).
The latter especially corrects a position that is simply taken for granted in
much secondary literature. Vidu rejects the assertion that the immanent
Trinity is the economic Trinity—widely popularized by Rahner—noting that
such a claim compromises divine transcendence (105). Each person acts
according to his distinct personal mode, but this is only visible in the created
order “in the form of final causality,” that is, in the drawing back of rational
creatures to God through the distinct missions of the Son and the Spirit (106).
Vidu explains that because the divine persons act together inseparably in the
created order, we cannot know the persons in their distinctness through
created effects that we see in the world; we have knowledge of the three
divine persons through the missions of the Son and the Spirit (113). With this
knowledge, we can appropriate common attributes or operations to distinct
persons to gain insight into the persons’ properties (112, 114). Vidu concludes

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that social Trinitarianism is at odds with monotheism in its conception of
three exemplars of “God” (116) who essentially have different jobs but work
together in agreement. Even so, he is sympathetic to its best intuitions of a
strong notion of distinct personhood (122).
In chapter 4, Vidu investigates the topic of the Trinity in the act of
creation. He considers the account offered by Tradition (126-36), two modern
critiques of the traditional account (136-40), patristic accounts of inseparable
operations in creation (140-46), and Aquinas’s account of creation as a
Trinitarian act (146-56). God creates each thing through an idea of it in the
divine intellect; thus, God is the exemplar cause of all things, in addition to
being the efficient and final cause of all things (134). Vidu shows that
corrected Platonic themes are redeployed in service of the Gospel by
Augustine (144-45) and Aquinas (146). For Aquinas, the Father creates
through the Word and in Love, where the Word is understood as the
exemplar of all creatures; the divine processions are the cause and exemplar of
the procession of creatures; all three persons act inseparably here (145-46,
149-50).
Chapter 5 takes up the question of the incarnation of the Son alone, in four
steps. Vidu distinguishes the common action of the divine persons in uniting a
human nature to the Son from the state of being united to a human nature,
which is proper to the Son (159-63). Vidu then considers the personal causality of the Son upon the human nature (163-66) before examining the consequences of termination (166-71): The Son is the term of the Incarnation in the
sense that the action of assuming terminates in the Son alone (167-68), but the
Holy Spirit is the term of all actions in the economy as the “perfecting cause”
(168) in whom the Father and the Son act. Finally, Christ’s human nature
reveals the Son (171-78) by completely receiving his personal filial mode—for
instance, his “eternal receptivity” and “return[ing] everything back to the
Father in love,” which is manifested on a human level as obedience (177).
Chapter 6 is on Christology and Trinitarian agency, which Vidu covers in
five parts. Concerning the witness of Tradition (182-85), Vidu reports
Aquinas’s clear distinction that “the human operation, in which the Father and
the Holy Spirit do not share, except by Their merciful consent, is distinct from
[Christ’s] operation, as the Word of God, wherein the Father and the Holy
Spirit share” (184). In pondering persons, natures, and actions (185-93), Vidu
notes that, after Scotus, nature became separated from will and action:
whereas the patristic strategy was to argue from same action to same nature,
the modern inclination is to argue from distinct action to distinct person
(185). With respect to the actions of Christ’s human nature (193-202) and
theandric action (202-9), Vidu observes that for Scotus, the actions of the
human nature are its own and are only predicated of the Son on account of its
union with the Son (196); for Aquinas, by contrast, although the human
nature has its own operation on the human level, as an instrument of the
divinity, it does not have a distinct action, but is an instrument in the principal
agent’s action (201). In his discussion of Christ’s suffering (209-213), Vidu

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intends to avoid Patripassianism by attributing actions inseparably to all three
persons but attributing passions only to the Son (210).
Chapter 7 takes up atonement in four steps. In reflecting on whether
human actions can bear upon divine actions (218-27) or whether humanity
has a necessary place in a divine mission (227-29), Vidu replies in the
affirmative but only as a “consequent condition.” That is, the Son needs his
human nature to be filled with the Holy Spirit in order to send the Spirit to us
(220), not absolutely but only as a condition consequent upon God’s plan to
work through his human nature. Concerning the necessity of Christ’s death
(229-38), Vidu concludes that in taking on our human nature, Christ
experienced divine condemnation, and the Crucifixion was inevitable yet not
as the cause or antecedent condition of reconciliation but as the necessary
manner of manifesting it (238). Vidu sees the Spirit’s role in atonement (23877) as necessary (238); and this “at-one-ment” effects the full pneumatization
of Christ’s human nature (246). Christ’s death was necessary not in order to
obtain a reward—as God does not react to any creaturely action—but
“because the way to new and divine life goes precisely through the old nature
with its death” (243).
Ascension and Pentecost are the topics that concern chapter 8. In the first
of five sections, Vidu reviews some historical explanations (248-51), noting
that some Protestant authors speak of Christ’s ability to send the Spirit as a
reward for his obedience—an idea not present in the Fathers, such as John
Chrysostom (249). Vidu then discusses the missions (251-54), especially
concerning Christ’s human nature in sending the Spirit (254-66); he approves
of Aquinas’s explanation that Christ is a cause of grace in us through his
meriting to be such a cause, where his human nature is an efficient instrument
cause (255). He departs from Aquinas’s position that Christ had the fullness of
the Spirit in grace from his conception, arguing instead that Christ received
this at his baptism (264). This accords with Vidu’s understanding that Christ’s
human nature was gradually deified to the point where he could give the Spirit
to us (266-74). In his interpretation of Christ as a life-giving spirit (274-77),
Vidu maintains that it is the Spirit’s role to make Christ present to the Church
after his Ascension “in the same way as in the Old Covenant the Spirit
mediated YHWH’s presence to Israel” (275).
In chapter 9, Vidu examines the indwelling of the Holy Spirit as Love, in
six sections. He reports on the “appropriation tradition” (281-83), which
appeals to appropriation since it respects the inseparable action of all three
divine persons in producing the indwelling of the Spirit. He then considers
critiques of this tradition that judge it to underappreciate the distinction of
persons in actions in created order (283-88), and then he critiques these
critiques (288-94) for risking introducing change and composition into God in
disregarding the principle of inseparability. Vidu defends the appropriation
tradition and, with the help of Aquinas, introduces an understanding of real
relations to distinct divine persons in the baptized, based on exemplar
causality, not efficient causality (294-300): we are conformed to and led back

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to the Son and the Spirit in grace through the gifts of wisdom and love (299).
The graced created effect of love does not buffer the Holy Spirit (300-302),
like a layer of mortar between bricks; it is rather like the seal in wax (313). It
is simply the effect of regeneration and the possession of the Spirit (302); thus,
the priority of the Spirit himself as uncreated grace is retained. Vidu wishes to
enhance Aquinas’s account (302-17) by emphasizing more strongly the
Christoformation of the Spirit’s indwelling through the human nature of
Christ (312).
Overall Vidu’s exposition and conclusions assist in faith seeking understanding; however, there are a few cases where his positions seem difficult to
square with Scripture and Tradition, and there are a number of ideas whose
formulation could use improvement. For instance, the overall context in
which Vidu situates all of his theological claims is a word game, according to
“Wittgenstein’s conception of ‘theology as grammar’” (xiv-xv; see also 95,
103, 114, 163, 319-20). But if our words, as limited and fragile as they are, do
not attain the reality signified in our speech about God, then it is difficult to
see how “we are called to witness to the reality of God’s dealings with us”
(xiv), as Vidu recognizes we in fact are. If the ultimate reach of our assertions
is a word game, then as long as our theological claims obey the rules, reality—
which is precisely what eludes us here—seemingly cannot be our guide.
Regarding some difficulties in formulation, Vidu writes that “the Word too
is spoken, or breathed out” (57), but it is the Spirit who is breathed out.
Moreover, Vidu in different ways confuses spirated with spirating (67, 71,
251), seeming to lose the difference between active and passive spiration—the
latter alone being the same as procession. He asserts that “the relations
(paternity, filiation, spiration—active and passive) constitute the persons as
such” (100), but this would make four divine persons; in fact, active spiration
does not constitute a person. Vidu claims that “the relations establish the
processions” (100), but it is the processions that establish relations. Furthermore, the divine essence does not proceed, as Vidu asserts (106); if it did,
there would be at least two essences. And he states that “there is a single
person in whom two natures subsist” (193), but in fact there is only one that
subsists—the single person, who subsists in two natures.
Because of space constraints, I can only list a few more difficulties, without
comment: the Son is distinct from the Father and the Spirit “because the
human nature that he assumes takes on the existence of the Son and acquires
the personal property of the Son” (202); “to say that the Son is begotten by
will is . . . simply to specify the manner in which the Son proceeds from the
Father” (61); “suffering can be predicated nevertheless of the divine essence”
(211); “[The human nature of Christ] exists as proceeding from the Father”
(205); “it is an outstanding question whether the incarnate Son shares in the
divine efficient causality of creation, or whether some other account can be
given of his participation in the activity of creation” (140); “to eliminate from
the explanatory apparatus for actions the prepersonal dimension of willing, or
natural willing, renders any account of action deficient” (110); and the human

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nature of Christ is an esse secundarium (168, 211), but the human nature has
no esse secundarium (216, 278).
Vidu initiates an important discussion and lays out an extensive defense of
the hard inseparability of the divine persons in their actions ad extra. He
elucidates the key principles by gathering and analyzing a rich dossier of
biblical texts, patristic sources, Thomistic doctrine, and contemporary authors.
This work would especially benefit professors and more advanced students in
theology, who would be more prepared for the depth of the discussion and
more ready to bring their own critique to Vidu’s interpretations.
JOHN BAPTIST KU, O.P.
Dominican House of Studies
Washington, D.C.

From the Alien to the Alone: A Study of Soul in Plotinus. By Gary Gurtler, S.J.
Washington, D.C.: The Catholic University of America Press, 2022.
Pp. ix + 269. $75.00 (cloth). ISBN 978-0-8132-3451-9.
Plotinus admitted, ruefully I would imagine, that Plato sometimes spoke
“enigmatically” about the soul. Thoughtful readers of the dialogues will find it
difficult to argue with this claim. Although Plotinus never thought of himself
as anything other than a Platonist and an accurate expositor of Platonism, his
reflections on many issues regarding “soul” (psychē) led him frequently to go
beyond the explicit words of the text and both to speculate on their
implications and to defend a Platonic account of the soul against opponents.
Herein lay Plotinus’s originality: drawing out the implications of Platonic
claims and addressing arguments against, in particular, the immateriality and
immortality of the human soul.
Students of Plotinus know that the fourth Ennead is entirely devoted to the
soul and psychological matters, broadly speaking. But there is hardly a treatise
among the other five Enneads that does not provide us with additional insight
into how Plotinus struggled with the problems regarding the soul and how he
“located” it within the Platonic system. Students also know that the fourth
Ennead contains nine treatises that were written over many years; they do not
represent a chronologically coherent or ordered set of papers on a single topic
or group of topics. Thus, we have treatises chronologically numbered 21, 4,
27-29, 41, 2, 6, 8 (out of a total of 54). Most of the secondary literature on
the soul in Plotinus focuses on the fourth Ennead with ancillary material
drawn from elsewhere. This is not wrong or hermeneutically unsound, but it
does suppose a topic-oriented approach on Plotinus’s part that probably does
not correspond with reality. One of the distinctive features of Gary Gurtler’s

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monograph is that he intentionally ignores the fourth Ennead and instead
focuses on a chronological commentary on passages in several major treatises
wherein the soul is discussed. This unusual approach certainly comes across as
an intriguing novelty for those already familiar with all the treatises. I wonder,
however, if such an approach would not be found disorienting by someone
not steeped in Plotinus. So, this is not a book for beginners or even for those
who come to Plotinus from a study of Plato, Aristotle, and the Stoics,
wondering how he internalized and reacted to some six hundred years of
intense philosophizing about the soul.
The treatises commented on (in part) are chronologically 1, 9, 10, 12, 19,
20, 22-23, 26, all roughly from Plotinus’s “middle period.” They are: I.2 [19]
(On Virtue), I.3 [20] (On Dialectic), I.6 [1] (On Beauty), II.4 [12] (On Matter),
III.6 [26] (On the Impassibility of Things without Bodies), V.1 [10] (On the
Three Primary Hypostases), VI.4-5 [22-23] (That Being, One and Identical, Is
Simultaneously Everywhere Whole), and VI.9 [9] (On the Good or the One).
The variety of topics discussed in these treatises is considerable. Gurtler’s
strategy is to approach the account of the soul from a number of different
perspectives, especially in its relations to intellect, the Good, the body, and
matter. All of this is done with the assumption that, as Plotinus thought about
the topics in these treatises, he continually added new perspectives on the
soul. Gurtler agrees with most scholars that there is no profound
“development” in Plotinus’s thinking over the relatively short period in which
he wrote these treatises. Nevertheless, this certainly does not preclude the
likelihood that his views on the soul were more and more profoundly
integrated within his larger metaphysical framework.
After an introductory overview of the material to be covered and the
methodology to be employed, Gurtler begins in chapter 1 to consider our
embodied experience of beauty as this is described in Plotinus’s first treatise,
On Beauty. Gurtler’s central insight here arises from his focus on the
experience of physical beauty, that is, its “psychic nature.” For Plotinus,
beauty is form which can be present in the admiring soul as much as it is
present in the body. The experience of beauty is, for Plotinus, transformative
because the beauty—not a representation of it—is in the soul. And since form
is closer to the One or the Good than is form plus body, beauty elevates us in
the direction of our ultimate destination. And for this reason, beauty moves us
beyond the limitation that form is or has to the unlimited or infinite first
principle of all. Gurtler finds in the treatise On the Good or the One a
complement to On Beauty, that is, a reversal of the perspective from ascent to
descent or production. Ascent to the One is for embodied human beings a
matter of reversing the dispersal of the person into a plurality of subjects of
embodied experience. The aim is to reverse the otherness of all pluralities with
respect to the One. Our own “oneness” needs to be cultivated by a precise
series of steps beginning with alienation from the body and ending with
identification with intellect. This identification is variously represented by
Plotinus and by Gurtler, but it comes down to reflection on the true good that

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we all want and an awareness that the psychic “we” that wants nothing but the
true good is the subject of intellectual activity, especially contemplation. Our
gradual alienation from our otherness in relation to the One turns out to be
the homecoming to which we all aspire.
In the second chapter, dedicated to On the Three Primary Hypostases,
Gurtler situates the embodied soul within the broad metaphysical framework
famously articulated in this important treatise. One of the central tasks of any
interpreter of this treatise is to distinguish the individual human soul from the
soul of the cosmos and also from the hypostasis Soul. Gurtler rightly makes
central to his account the striking claim of Plotinus that soul is matter to
intellect as form. What this means, among other things, is that our intellects
are present in all our psychic activities. Although Gurtler does not mention
this, I take it that this suggests that all our so-called irrational behavior is in
fact the behavior of a rational animal and that the irrationality is purely
normative. By this I mean that the behavior goes against a standard of
behavior that one has reason to believe the agent himself endorses. As for the
above issue of distinguishing the soul from the hypostasis, Gurtler does not
quite resolve the issue, although he seems to suggest that the hypostasis Soul is
just the life of the hypostasis Intellect, eternally cognitively identical with the
Living Being, as is stated in Timaeus. I should add that in this chapter, Plotinus
obviously has the great Parmenides in view in his account of being and
oneness and Gurtler makes effective use of Plotinus’s introduction of
Parmenides in this regard.
Chapter 3 concerns the difficult but portentous treatise On Matter and
Plotinus’s rejection or rather reinterpretation of this fundamental Aristotelian
concept in Platonic terms. Aristotle argues that form, matter, and privation are
the basic and irreducible principles of change. Plotinus responds that there is
no difference between matter and privation if we consider prime matter. But if
that is the case, then what is called “proximate matter” is not matter at all but
actually an additional hylomorphic composition. Thus, real matter is totally
incorporeal. As Gurtler shows, the consequences of this reconceptualization of
matter are immense for Plotinus’s understanding of the embodied soul.
Specifically, matter cannot affect soul because matter is unqualifiedly inert.
The “impassivity” of soul in regard to matter is thus secure. How then can
embodiment be a locus of peril for the soul? Because embodiment entails a
“dispersal” of the soul into a plurality of subjects of embodied states. What is
open to corruption—and to punishment via reincarnation—is the soul-body
composite alienating itself from its own good. So, it turns out that reflection
on matter refocuses the philosophical reflection on the soul and the challenges
of embodiment. In addition, matter is no longer to be viewed as itself evil but
rather more as the terminus of a trajectory on the path of a soul that has lost
its way. In contrast to matter in the sensible world, intelligible matter cannot
be the receptacle for the instantiation of Forms, since in the intelligible world
all the Forms are internally related. That is why Being is, as Plotinus says, a
“one-many.” Intelligible matter does not underlie body, but rather substance

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or ousia, allowing for the articulation of the array of intelligibles by an eternal
intellect. Gurtler suggests, all too briefly, that the hypostasis Soul is intelligible
matter, a claim which, if true, would illuminate the account of the procession
from the One according to which intelligible matter seems to be Intellect prior
to its full “formation” by its reversion to the One and its achievement of the
Good insofar as this is possible for any intellect.
In the fourth chapter, Gurtler examines Plotinus’s remedy for alienation:
virtue. Following a Platonic tradition well-established by his time, Plotinus
distinguishes among grades of virtue especially as these are articulated and
implied in Plato’s Phaedo and Republic. The civic or popular virtues revolve
around the restraint of the body; philosophical virtue is aimed at the
identification of the embodied self with intellect and the consequent alienation
from the body. This is the simple story, although later Platonists add nuance.
For Plotinus, dialectic is the name for the practices or exercises that facilitate
this identification. Another name for it is “philosophy.” Gurtler nicely links
the acquisition of philosophical virtue with the erotic attachment to
intelligible beauty discussed in the first chapter.
The fifth and sixth chapters may be considered together since they concern
what amounts to one long and complex discussion in which Plotinus tries to
explain how the eternal immaterial world is related to the sensible world.
Gurtler notes that the seemingly incongruent characteristics of immanence and
transcendence, when applied to the intelligible world in relation to the
sensible world, emerge with an explanation of how the body is related to the
soul. Gurtler shows that the problem Plotinus addresses is the common
mistake of viewing the intelligible world as an abstract representation of the
sensible world when in fact the causal line is exactly the opposite. This error is
the primary reason for objections to participation. The key to Plotinus’s
approach is to recognize that the intelligible world is eternally present everywhere and all at once to anything capable of receiving it and exactly to the
extent that they are capable. This principle, as applied to soul in relation to
body yields the result that soul is everywhere in the body and there at all times
and the various parts of the body receive as much of it as they are able. As
much can be said for Intellect’s presence to individual human souls. The
“moral alienation” of the soul, as Gurtler terms it, should be understood as an
inclination to the separation provided by corporeality and disinclination to the
unity that Being’s presence involves. Finally, the above distinctions lead to the
account of the transcendence and immanence of the first principle of all, the
Good or One. As Plotinus says in V.1, the Good is in us, but it is so according
to the capacity of the receiver. At the same time, that presence does not
exclude its transcendence, but entails it because any presence can only be a
complex manifestation of the absolutely simple first principle. So, everything
either advances towards unity or continues on a deviation from it, but each
according to its own capacity and habits. Thus, our undeniable desire for our
own good turns out to be identical with our desire for the Good itself.

BOOK REVIEWS

171

The seventh and final chapter is really a continuation of the third chapter,
matching up the incorporeality and impassivity of matter with that of soul.
This chapter contains a discussion of Plotinus’s arguments against Stoic
materialism in III.6, the details of which must be left out here. Whereas the
impassivity of matter ensures its utter inertness, the impassivity of soul entails
its everlasting activity. Thus, Gurtler ends where he began, with the
experience of soul.
The book has a brief concluding chapter highlighting the main claims made
and issues addressed.
Gurtler’s decades-long encounter with Plotinus has resulted in a very
thoughtful book from a rather unusual perspective. As I said at the beginning,
someone new to Plotinus might not be able to profit all that much from its
allusive nature. Like the corporeal in relation to the incorporeal, the reader
will benefit from Gurtler’s reflections according to his or her capacity for
reception.
LLOYD P. GERSON
University of Toronto
Toronto, Ontario, Canada