THE PHILOSOPHICAL DIMENSIONS OF THE ORIGIN OF SPECIES.
John N. Deely
University of Ottawa
Ottawa, Canada
PART TWO
VI. The Error of Univocally Ontologized Kind-Essences
From the title of this section one might expect it to develop the contention that the specific structures causally accounted for by contemporary science are contrarily related to the texture and sense of the traditional principles governing the recognition of specific distinctions in the world of bodies. Perhaps unfortunately, we must develop a rather more complex contention.
The contention to be developed at this point is that an ontological survey of the landscape of Darwin's world shows that, so far as its metaphysical structure is concerned, the knowledge of evolutionary species has not altered the structure of the traditional species problematic but has, on the contrary, clarified its secondary implications so as to make its options clearer and their alternatives more definite. In showing this, the survey in question shall have, on the one side, to clear away the morass of philosophical perplexities in post-Darwinian thought due not to the accumulation of evolutionary data (as Dewey thought and as commonly supposed) but primarily and directly to those ambiguities and uncertainties latent in Classical Antiquity's notion itself of species, whose features the labor of evolutionary research has forced to the fore. This will be the direct concern of the present section. On the other side, it will remain to show that the forthright acknowledgment and philosophical resolution of these no longer latent ambiguities and uncertainties render the evolutionary data themselves more intelligible in their own line of explanation which is not mathematical (species are not numbers) but that of natural philosophy, wherein are assigned reasons for the changes that never cease around us. This will be the concern of Section VIII below, where the problem of the criterion of evolutionary progress at last comes into view.
Page 252
Mortimer Adler was perhaps the first to see clearly and perhaps the only one to state clearly that " most of the philosophical perplexities in post-Darwinian thought are due to ambiguities and uncertainties in the notion of species itself rather than to the discovery of any radically significant facts."153 The ambiguities and uncertainties in question, I think, can be traced to seven sources, four of which are matters of properly philosophical argumentation, one socio-cultural, one psychological, and one theological.
1) Most fundamentally, it was the enculturated conception of the eternal heavens which deflected even the most penetrating of the classical and medieval analyses of the ontological character of the natural kinds encountered in common experience.154 Since the unchanging
153 The Problem of Species, p. 10.
154 For Aristotle and St. Thomas, it was the eternal space-time of the celestial spheres which determined the place and order of sublunary bodies, and so the rigid necessity and formal immutability of their natures. The Aristotelian essences of material beings do not have their cosmological reference to what we understand today by the physical environment but to the unchanging heavens which, as instruments of the separated intelligences, were regarded as the causa regitiva, the governing cause, of the physical world. E. g., cf. St. Thomas, In III Met., lect. 11, n. 487: ". . . in the twelfth book [1073a14-1073b17; in Comm., lect. 9, " The Number of Primary Movers "] . . . the Philosopher shows that the first active or moving principles of all things are the same but in relation to a certain order or rank. For first indeed are the principles without qualification incorruptible and immobile. There are, however, following on these, the incorruptible and mobile principles, to wit, the heavenly bodies, which by their motion cause generation and corruption in the world." In Bk. VII, lect. 6, no. 1403, in connection with the question of spontaneous generation, reference is similarly made " to the power of the heavens, which is the universal regulating power of generations and corruptions in these lower bodies. . . ."
For a full discussion, see Thomas Litt's study of Les Corps célestes dans I'univers de saint Thomas d'Aquin (Paris: Nauwelaerts, 1963), from the " Introduction " and " Conclusion" to which the following observations indicate the justice of my own allegations in this matter: " L'opinion courante, dans le monde des spécialistes de S. Thomas, est que la théorie des corps célestes reste parfaitement extrinsèque à l'enseignement philosophique ou théologique du saint docteur. Et ce qu'il y a d'étrange, c'est que cette opinion, non seulement est adoptée communement sans preuves, sans examen, mais qu'elle ne se formule même pas. Non seulement on escamote les corps célestes sans démontrer qu'on a le droit de les escamoter, mais on les escamote sans même le dire. . . ." (pp. 5-6) " Mais il y a au moins deux points de l'enseignement de S. Thomas où les corps célestes . . . entrent vraiment dans la doctrine elle-même, où, par conséquent, on altère ladite doctrine, si on les escamote . . . d'abord quant à la théorie de la matière et de la forme." (p. 6) Deuxièment, quant " à la doctrine des séries de causes subordonnées essentiellement." (p. 9) Mais aussi " il y a un troisième point où la théorie des corps célestes à eu une influence intime sur la doctrine philosophique de S. Thomas, et c'est, ni plus ni moins, la très générale et très fondamentale théorie de l'acte et de la puissance. L'univers de S. Thomas éta'it fait d'êtres qui passaient de la puissance à l'acte, c'est-à-dire, de l'imperfection à la perfection correspondant à leur espèce. . . . Ici encore, par consequent, une adaptation est nécessaire, si l'on veut transplanter la théorie de la puissance et de l'acte dans notre univers à nous." (pp. 11-12) " Les . . . chapitres de cet ouvrage montrent [que] ... la métaphysique "--ou bien, la cosmologie ou " scientia naturalis "--" des corps célestes . . . est incontestablement une pièce constitutive de la synthèse philosophique du Docteur commun et elle porte la marque de son genie propre: ses conceptions sur la nature et l'action des sphères célestes prennent place dans une vision grandiose de l'ordre universel; tous les aspects de cette cosmologie typiquement médiévale se complètent d'une manière rigoureusement cohérente et révèlent l'esprit de synthèse si caractéristique de la pensée du maitre." (p. 367) " La cosmologie des sphères célestes joue également un rôle dans la synthèse thèologique de S. Thomas." (p. 370) " Une . . . question, capitale pour les thomistes actuels, se pose aussitôt: le système philosophique de S. Thomas peut-il être amputé, sans inconvénient serieux, de la pseudo-métaphysique [pseudo-cosmologie] des sphères célestes? Ici une distinction importante s'impose. II est impossible de comprendre et d'exposer fidèlement le système élaboré par S. Thomas au XIIIe siècle en passant sous silence sa cosmologie céleste. . . . Mais le mouvement de renaissance thomiste ne peut pas être et ne veut pas être une restauration servile du thomisme médiéval. L'école thorniste contemporaine entend s'inspirer des enseignements du Docteur commun dans la mesure où ils s'avèrent capables de promouvoir l'essor d'une philosophie authentique, répondant aux requêtes de la pensée critique. Dans une telle entreprise, il est possible de reprendre à S. Thomas les thèses essentielles de sa métaphysique tout en sacrifiant les conceptions pseudo-métaphysiques et pseudo-scientifiques de sa 'physique céleste '. Celles-ci, en effet, sont des applications erronées ou imaginaires des principes métaphysiques, elles ne conditionnent pas ces principes.
" Mais il ne suffit pas de supprimer, il faut remplacer. Les philosophes thomistes d'aujourd'hui se trouvent devant la tâche redoutable de mettre sur pied une nouvelle cosmologie, une nouvelle philosophie de l'univers matériel, et notamment une reponse valable au problème de la finalité dans l'univers matériel en même temps qu'une épistémologie et une critique des sciences. L'oeuvre est à peine commencée. L'enquête qui s'achève ici montre combien cette oeuvre est nécessaire." (p. 372)
page 253
spheres determined and governed the place and order of sublunary bodies, guaranteeing the rigid necessity and formal immutability of their natures, there could be no question of a speciation process altering across the ages the visible features of the natural world.
2) This socio-cultural background made it all but inevitable that the metaphysical notion of essence as a radical kind should be directly applied to all the natural kinds which are intuitively recognized, such as birds and fishes and oysters, even though each of these groups combines a multitude of differentiae and cannot be classified by a single difference as in a dichotomy; and even though, according to the metaphysical definition of an essential difference, things are constituted as distinct in kind only if they differ by a single ultimate difference or formal factor--differ the way traditional philosophy could distinguish only between corporeal, living, sensitive, and rational.
3) This equivocation in the application of " essence " to the natural kinds inevitably led to a focal reduction of ontology to logic, to the extent that it was necessary to predicate essential differences and thus to distinguish the species of nature not on the basis of properties in the strict sense but on the basis of a syndrome of accidents interpreted as extrinsic and empirical signs of the property convertible with the essence (see fn. 157 below).
4) Just as in order to maintain the equivocal use of the notion of essential kinds it became necessary to supplant the ontological notion of property by the logical notion, so as a result of this ambiguous criterion of specific differences the ontological problem about species (how many " essential" species or radical kinds are there?) entered into a circular interdependence with the epistemological problem (how many " essential" species or radical kinds do we know?) ,155 For a long time this covert and unnatural symbiosis of ontology with logic went unnoticed;
it seemed to entail no more than the fact that our knowledge of nature is imperfect and that, so long as observing and thinking men are at work, there is always the possibility that new species may be discovered. But, as the
155 See fn. 16 supra.
page 255
investigation of nature progressed, it not only became clear that new species in the sense of natural kinds were there to be discovered, it also became clear that none of the natural kinds were fixed in form 156 and that there was
156 " Plaçons-nous maintenant au point de vue de la nature prise au sens strict de ' principium et causa motus et quietis ejus, in quo est primo et per se, et non secundum accidens.'--Natura determinata est ad unum. Voilà un principe donl on ne cesse d'abuser. On se fait d'habitude une idée trop homogène de la nature, comme si toute nature était egalement nature. Ne faudrait-il pas dire plutôt qu'il n'y a nature que dans la mesure où la matière et la forme sont déterminées? Si la forme avait d'elle-même une détermination parfaite, elle ne serait plus nature. Remarquons que nature se dit non seulement de la forme, mais aussi de la matière du composé." Charles De Koninck, " Réflexions sur le problème de l'indéterminisme," Revue Thomiste, XLIII (1937), pp. 236-7. See John of St. Thomas, Cursus Philosophicus, II, pp. 180 ff. (Reiser ed.).
This point is important and difficult enough to require a decisive clarification. Such is achieved, I think, in the following text from Adler, where in the form of objection and reply he is defending the view that there are a small number of ontological or essential species (radical kinds), definitely less than ten, against the objections raised by those of the view that there are a very large and undeterminate number of such species. The former Adler refers to as the " first position " or theory, the latter as the " second." (From The Problem of Species, pp. 195-8)
" Objection 4. In addition to those already cited (Obj. 3 contra 1) [see fn. 157 below], there are other well-attested facts which are difficult to explain according to the theory of the first position. The facts of procreation in the sphere of living things amply testify to the production of like by like. It is not simply that plants reproduce plants, and animals animals, but that this kind of plant uniformly tends to procreate organisms of the same kind, and similarly in the case of kinds of animals. Such uniformity in generation, furthermore, is connected with the aggregate of traits which constantly and peculiarly typify a kind of plant or animal; in other words, if a given kind is distinguished by an aggregate of traits found among all its members and only among them, the offspring will manifest the same traits in aggregate, and this is what is meant by like producing like. Thus, Monaco defines a species as ' a collection of individual living things which preserve the same powers and the same type through the generation of one from the other' (Praelectiones Metaphysicae Specialis, Pars II: de viventibus seu psychologia. Cap. I, Art. V, Th. XXIV; Rome, 1929, pp. 174-6); and his definition would hold for other accidents than power which, taken together, constitute the type.
" Now, it can be learned that Monaco and others, who take genetic uniformity as a sign of specificity, are right, by applying a fundamental principle to the facts cited. According to St. Thomas, ' the likeness of the begetter to the begotten is on account not of the matter, but of the form of the agent that generates its like' (Summa Theologica, I, 119, 2, ad 2). Furthermore, the substantial form is the, term of generation (i. e., substantial change). Hence to say that like generates like, in the reproduction of living things (Summa Theologica, I, 118, 1), is to say that the likeness between the begetter and the begotten must be in regard to substantial
no reason to believe that the syndrome of typifying traits by which the natural kinds could be classified were the
form. Wherefore we must conclude that if this kind of plant or animal generates its like in kind, i. e., if roses generate roses, and potatoes potatoes; if camels generate camels, and sparrows sparrows,--then all of these many kinds, which preserve their type throughout a series of generations, must be species. Otherwise, the term of generation would not be a substantial form, which is impossible. So it is shown that plant and animal are not infima species, but extensive genera including many specifically distinct kinds.
" Reply Obj. 4. Here as before the facts are readily admitted, but not the interpretation which the objection puts upon them. The interpretation is rejected for reasons which have already been made clear, namely, the role of signate matter in generation (Reply Obj. 3 contra 1). The signate matter, which is determinate not only in dimensions but in other accidental respects, is the source of racial and familial accidents, as well as individuating ones. Hence, the uniformities in biological reproduction are due partly to the substantial form, in so far as the offspring are like their ancestors in species, and partly to the signate matter, in so far as the progeny resemble their procreators in merely accidental respects.
" This will be seen at once if the facts are re-considered. There is uniformity in the generation of men of different races; thus, Caucasians generate Caucasians, and negroes negroes, if the breeding is restricted to individuals of the same stock. But we know that these are races, not species, and hence we must admit that this generation of like by like cannot mean that the term of generation is a substantial form, taken simply. It must rather be regarded as a substantial form (the principle of specific human nature) subject to further accidental determinations of a racial order. There is no more difficulty about this than that one individual should procreate another which is individually different because the substantial form which is alike in both begetter and begotten is, nevertheless, individuated differently in each, i. e., subject to further accidental determinations of an individuating sort. Nor need the begetter and the begotten always differ in their individual traits; they may also resemble each other in various accidental ways; but this cannot be due to their likeness in substantial form, since contingent accidents do not follow from the form. Hence it must be due to the condition of the signate matter in generation.
" In short, both racial and individual similarities between ancestors and progeny can be explained in the same way by reference to the role which signate matter plays in generation; in fact, they cannot be explained in any other way, because these similarities are with respect to contingent accidents, and they cannot be due to the substantial form. It does not follow, therefore, because roses generate roses, or camels camels, that these ' kinds ' are species. If there were other and independent evidence that rose was a species, there would be no need, of course, to have recourse to uniformity in generation to prove the point. But since such evidence is either lacking or not relevant, the facts of generation by themselves are totally insufficient because they can be, and must be, otherwise interpreted.
" The error which the objection makes is to suppose that form is always the principle of sameness and matter of difference; whereas, as we have seen (Reply Obj. 3 contra I), things may be specifically different in respect of form, and alike because of material accidents. And this applies also to the like and the unlike in the process of generation: matter, as signate, is the source of both differences and similarities of an accidental sort, whereas substantial form is the principle of essential sameness and distinction. Furthermore, the authority of St. Thomas in this connection may be disregarded, for what he says in the text cited is explained by his unavoidable ignorance of facts about generation which modern researches have discovered. In that same text (op. cit., I, 119, 2, ad 2), he writes: ' In order for a man to be like his grandfather, there is no need that the corporeal seminal matter should have been in the grandfather; but that there be in the semen a virtue derived from the soul of the grandfather through the father. . . . For kinship is not in relation to matter, but rather to the derivation of the forms.' But we know that there is a continuity in the germ plasm which is transmitted from generation to generation, as well, of course, as variability in its microscopic structure. It is, thus, in terms of the matter that relations of kinship are to be explained, and not simply through the derivation of forms. Both principles are required if we are to account for both specific nature and accidental traits, racial or individual, whether we are considering the similarities or the differences of living organisms. Error results from ignoring either principle, as the ancients from excusable ignorance neglected, in part at least, the contribution made by signate matter; and as some moderns from culpable neglect of philosophy, fail to take account of substantial form and hence either deny true species or else futilely seek to explain all uniformities in generation by reference to material dispositions.
" Finally it must be acknowledged that, in answering this objection and the previous one, we have presumed to speak about the nature of generation and the role of signate matter therein, without undertaking a complete analysis of these matters. The presumption seems justified, however, in the light of the traditional discussion of such problems."
page 257
signs of a single specifying difference, of a property in the strictest ontological sense.157
157 This point is the very hinge of the issue. Its importance and the range of misunderstandings centered on it make it impossible to avoid citation in order to remove all equivocation and ambiguity in a decisive fashion. The text which achieves this is from Adler's early work on The Problem of Species, pp. 188-195; we shall cite only pp. 189-91.
" The fundamental error ... is a confusion of the logical and ontological meaning of ' property,' similar to the confusion of the logical and ontological meaning of ' species,' which has already been pointed out (vd. Obj. 5 contra II). Convertibility in predication is the logical criterion for calling an accidental term a property of a substance. The formula ' quod soli et semper et omni convenit ' merely states this criterion; this criterion or formula is a necessary, but not a sufficient, condition of something's being a property in a strictly ontological status. It is true that every accident which is a property is, in logical discourse, represented by a term convertibly predicable of its substantive subject; but not every term which is so predicable is ontologically a property. There are three other criteria, which must be satisfied: 1) The property of a substance must directly signify the substantial difference which cannot be directly apprehended; thus, rationality as a property signifies the substantial difference constitutive of human nature; 2) the property itself is never directly apprehended, but always known by the observation
At this point the problem was further vitiated by Darwin's denial not only that all or many of the natural kinds were distinct in the philosopher's sense of essentially or " radically " so but even distinct in kind at all. In other words, Darwin set up a three-sided issue in terms of a two-sided option: either the beings of nature differ in kind, or they differ only in degree, and specific distinctions are entirely of human making (quoad nos) . We have seen how subsequent researches in science proved Darwin wrong about the metalogical status of species and how subsequent analyses in philosophy proved him wrong about the modes of difference. We can extend this to much of what Adler says concerning the dispute about the uniqueness of man to the dispute about the nature of the difference between the living and the non-living and between plants and animals:
of other perceptible accidents, especially operations, actions or passions; 3) the property must not only follow necessarily from the substantial form, but it must be due to the form alone, and neither to the signate matter nor to the objective circumstances of the thing's existence or operation. By these three criteria, power and power alone can be the property of a substance. Not even the natural habits of a substance,--those constant and peculiar modifications of its powers which arise from its normal operations,--are properties. That risibility is traditionally said to be a property of man indicates how prevalent in the tradition is the confusion of logic and ontology; risibility, like the ability to speak grammatically, or to make things artistically, are certainly properties, in the logical sense; but when examined ontologically they are merely aspects of rationality in relation to the variety of objects with respect to which man operates. A sense of humor and grammatical speech are ' natural arts ' of man, constant and peculiar modifications of his rational powers functioning, as they must, in cooperation with sense and other bodily powers. If these are not powers, and hence not properties, how much less so are modes of operation which depend merely upon peculiarities of bodily arrangement or objective circumstance; and even less are such things as figure, color, duration, place, etc. For all these are directly observable accidents; they obviously do not follow from the substantial form alone; nor do they signify a substantial difference directly, as the intellectual powers of man, the proper accident of human nature, signify rationality, as the substantial difference, united with animality, as the generic nature, in the constitution of the human essence. Although we have discussed the essence and property of man, because the second position admits man to be an infima species, what has been said here applies universally to the relation of essence and property. Therefore, we must conclude that none of the so-called constant and peculiar accidents mentioned in the objection are properties (necessary or proper accidents). They are all contingent or adventitious accidents."
Most, if not all [modern authors] have approached the question with too few distinctions explicitly in mind. They use the words " degree " and " kind " without qualifying them by such critical modifiers as " real " and " apparent," " superficial " and " radical." The reader will find that the philosophical and scientific literature on the subject of man's difference is simply not intelligible without these distinctions, especially the distinction between a radical and a superficial difference in kind.158
Yet in fact traditional philosophy and evolutionary science are generally considered to be antipathetic, notwithstanding this double advance. Here we are at the fourth and principal source of the still prevailing ambiguities and uncertainties surrounding the traditional notion of species as essentially distinct kinds: what started out in ancient times as a temporary dependence in ontology upon logical criteria for the determination of species, ended up in modern times as an abandonment of the principle of parsimony in the analysis of natural kinds. I think that when and if the history of neo-scholasticism is written, it will have at its disposal in the writings of Maritain, Garrigou-Lagrange, Rousselot, Gredt, Brennan, Maquart, and Phillips so far as they treat of species a classic illustration of the ancient adage, parvus error in principio magnus est in fine--a small initial mistake is a colossal error in the end.158a
If it is true that no theoretical constructs should be resorted to that can be dispensed with in explaining the phenomena, and if there is no evidence that any of the natural kinds recognized as species by modern biology exhibit the " infima specific " construction of traditional philosophy, then, by the stated principle which obliges us to judge in the light of the available evidence, we are
158 Adler, The Difference of Man, p. 32.
158a St. Thomas, De ente et essentia, " Prooemium." See also Aristotle, De caelo, I, c. 5, 271b8-13; St. Thomas, In I de caelo, lect. 9, n. 97. Averroes has the clearest formulation, In III de anima, cap. IV, Lyons 1542 in 16, f. 112V, comm. 4: " minimus enim error in principio, est causa maximi erroris in fine, sicut dicit Aristoteles."
forced to acknowledge that the metaphysical analysis of essence as constituted by a genus together with a unitary formal difference cannot be applied directly to the diversity and hierarchy of natural kinds so far as they are constituted by groups discriminable as such only by virtue of a syndrome of observable traits, so far, that is, as they are constituted by groups which " we must define at the outset by a multiplicity of differentiae." 159
The alternative, to whatever extent the principle is abandoned, is to engage in myth making. The point is that, in the present state of evidence, it is impossible to simultaneously respect the regulation of the principle of parsimony and appeal to principles proper to epistemology on questions concerning the metalogical (ontological) status and number of the radical kinds of being. This was illustrated in the famous distinction scholastics drew between " natural " and " systematic " species (Maritain speaks of " the ontological species, not the taxonomic species dealt with in botany, zoology or genetics " 160):
Three things must be distinguished: a) varieties (races); b) types now sharply distinct within the same species, i. e., systematic species; c) natural species. . . . The stability of systematic species is only relative; of the natural species, absolute. Nor can there be so much diversity introduced into the natural species through the systematic species as would obliterate their specific type, i. e., their specific organization. The only difficulty now is to discriminate between the natural and the systematic species. ... It is clear that we must consider brutes and plants as supreme genera, which are further divided into diverse natural genera and species. It belongs to biology, however, not philosophy, to determine what these genera and species are.161
159 Aristotle, De partibus animalium, Bk. I, ch. 3, 643 b 25.
160 Jacques Maritain, " Substantial Forms and Evolution," in The Range of Reason, p. 37.
161 Josephus Gredt, Elementa Philosophiae Aristotelico-Thomisticae, editio decima tertia recognita et aucta ab Euchario Zenzen (Barcelona: Herder, 1961), n. 611, p. 541. It should be noted here, however, first, how close Gredt's " tria distinguenda " are to the notions of apparent, superficial, and radical kinds; second, that since Gredt's time, the great advances in the knowledge of heredity and in the analysis of the genetic code (DNA/RNA) have seriously undermined the foundation on which Gredt rested his entire argument: " Ex organisatione stricte essentiali, quae rationem habet proprii stricte (quod soli et semper et omni convenit [notice here the confusion uncovered in fn. 157 supra between the logical and ontological meaning of property], cum certitudine cognosci possent omnes species naturales. Sed haec organisatio nos latet; consistit enim in ilia microorganisatione, quae jam habetur in cellula germinali (fecundata), unde incipit evolutio viventis(cf. n. 406; 449; 452, 2). Cum incipit evolutio viventis, anima seu forma substantialis specifica viventis jam adest, quae essentialiter concectitur cum hace microorganisatione. Haec enim microorganisatio est dispositio proxima ad eam. Evolutione viventis, quae divisione cellularum fit, haec dispositio stricte essentialis communicatur cum diversis cellulis. Sed haec microorganisatio fugit etiam investigationem microscopicam. Necesse est igitur discamus essentiales corporum viventium differentias ex typo externo, ex proprietatibus, quae in individuo vivente in decursu evolutionis suae extrinsecus apparet, ut jam indicavimus. . . ." What has already been discussed in sections IV and V above justifies, I think, the contention that, if one grants the validity of Gredt's premises here, then it is necessary in the light of now available evidence to draw from them conclusions not compatible with what Gredt himself contended. See the remark of Maritain cited in fn. 163 below.
Such a conception is truly a curio of history, inasmuch as it predates the " family quarrel' between Linnaeus and Darwin. Such a conception also belongs to the class of entia multiplicanda sine necessitate, of myth in the philosophical sense, inasmuch as the mass of data gathered in both the paleo- and neo-sciences favors a denial of these " natural species." Such a conception dialectically belongs to the order of non-argument, inasmuch as it posits an ontological distinction which it admits cannot be verified in a single known case and defends the validity of the distinction on the grounds of our ignorance, thus making the ontological problem a function of the epistemological problem.162 Finally, such a conception contradicts itself;
162 The confusion of logic and ontology in the Aristotelian-Thomistic species problematic perhaps reached its greatest depth at the time that Gredt could write (a passage not edited, be it noted, as late as 1961 in Zenzen's edition): " Evolutionismus ille, qui rerum distinctionem specificam tollit (darwinismus), arborem Porphyrii destruit" (op. cit., n. 160, p. 143). As Adler early pointed out, " the famous Tree is not purely a logical representation of the arrangement of concepts, but a confusion of logical with ontological ordering. Wherever the philosophical tradition has followed or been influenced by Porphyry, this confusion appears." Not only is " the error a characteristic consequence of the platonizing of Aristotelian science," but " one wonders whether the confusion of logic and ontology in the Porphyrian tradition is also a confusion of the orders of substance and accident." (The Problem of Species, p. 68 fn. 86, p. 70, respectively), See The Problem of Species, pp. 64-70. These pages must be read, however, in the light of the rectified theory of an ontological common genus as presented in " Solution of the Problem of Species "; and in this latter work, see also the " Historical Hypothesis," pp. 360-378, which essays to circumscribe in the Aristotelian writings the root sources of the ambiguities and uncertainties which have plagued the philosophical species problematic from the beginning.
See also Maritain's non-argument that " the true character of matter demands " that we should not be able to know, by essential definitions, any specific natures inferior to man (" Preface " to The Problem of Species, p. x), which objection is thoroughly rebutted by Adler in " Solution of the Problem of Species," pp. 345-50.
for the philosopher who entertains it, " while confessing his dependence on the scientist for knowledge of distinctions below plant and brute, he transgresses the sphere of his competence--violating the autonomy of science--by deciding what scientific evidence he will accept or reject." l63 What Mortimer Adler noticed in this regard thirty years ago, curiously, continues to be true today: " The problems which result from such errors and transgressions are false and ungenuine; yet, for the most part, these are the matters discussed when philosophers and scientists engage in controversy about evolution.' " 164
163 Adler, The Problem of Species, p. 269. Here then one may cite Maritain contre lui-même: " Given that philosophy is in its own right independent of the sciences . . . nevertheless . . . the sciences may indirectly reveal the falsity of this or that philosophical doctrine . . . if and. when a philosophical doctrine happens to encroach upon science itself or to have, as a necessary consequence, a certain scientific conception, or rather a certain general framework imposed on science, whose emptiness is demonstrated." (The Degrees of Knowledge, p. 59, my emphasis). Such has almost certainly been the case with the traditional philosophical doctrine of the infima species.
164 Ibid. And sometimes these pseudo-problems underlie the discussion of larger matters as well. For example, I think that Maritain's way of subdividing " empiriological knowledge of nature " into " empiriometric " and " empirioschematic " can be shown to depend in part on the position he adopts over the issue of the number and constitution of specific natures (e. g., see The Degrees of Knowledge, pp. 30-50, esp. pp. 31, 38, and 45; pp. 173-181, esp. p. 176 fn. 2, pp. 176-8, esp. p. 178; p. 205 text and fn. 1, pp. 206-9). Thus the philosophical dimensions of the problem of species have a definite bearing on the philosophy of science; and moreover, once the necessary corrections in the formulation of the species problematic have been achieved, I think it is possible to formulate a solution to the problem of the distinction and relations between science and philosophy which not only meets the requirements of the problem on both sides, but which also reconciles the views of Ashley, Adler, and Maritain in a higher synthesis (formaliter eminenter) to which each of them could give unqualified assent. This, of course, would have to be shown, for it constitutes a study in its own right.
5) Inescapably linked with the question of specific transformations is the problem of the assignation of causes. To some philosophers, the possibility of individuals giving rise to more perfect individuals seems a violation of the necessary proportion between cause and effect. We shall return to this in a later Section (VIII).
6) The two final sources of ambiguity and uncertainty in the traditional species problematic are closely linked. The philosophical tradition of Aristotle became in St. Thomas a theological tradition as well. The static view of natural kinds, originally rooted in the immutable heavens, seemed to the theologians of medieval times to be indicated in the scriptural texts as well, at least to the extent that the origin of any new specific form was an event involving a special divine creative act. In this way the immutability of specific natures came to mean that
the individuals of one species " cannot be generated by or generate [individuals of] another species through the operation of secondary causes alone." 1657) The final source of difficulty is a psychological one. Whatever one may think about a science, the architectural structure of which is authority and the foundation of which a text, it is not a mode of knowledge foreign to human nature. Man is by nature an authority acceptor as well as a reasoner.165a It is impossible to admit the
165 See Adler, The Problem of Species, pp. 202, 221, 228 fn. 110, 229-30, 251 et alibi. In fn. 110, p. 228, Adler wrote: " in the first occurrence of any new species, Divine causality must intervene," since generation by equivocal causality would be " impossible." (Although in fn. 285 on p. 275 he quotes De Koninck approvingly as saying that " when a superior nature is produced from the potency of an inferior nature by equivocal generation, this production remains natural.") From a recent telephone conversation, however, I am glad to say that he now is in agreement with the view that will be expressed in Section VIII below, namely, that it is impossible to demonstrate the impossibility in any case of the origin of an (ontologically) higher material form from an (ontologically) lower causal series, by reason of the reciprocal repercussion of the causes.
165a See C. H. Waddington's important study of man as The Ethical Animal (Atheneum, 1960). Thus, not only in the matter of specific natures but in a great many other problem areas as well, " Thomists, in principle, state that one should not rest on authority in matters philosophical, and yet de facto they have been doing precisely this," observes William A. Wallace in an article on " Thomism and Modern Science," The Thomist, XXXII (January, 1968), pp. 82-83.
page 264
natural origin of the natural species and reconcile all the traditional texts with the admission.166
Such then are seven of the major sources of ambivalence and equivocation in the traditional problematic of species: the notion of an unchanging causa regitiva keeping the relation of generator to generated within fixed limits; an insufficiently critical appraisal of the order of natural kinds in the light of the metaphysics of essential constitution; an abandonment of the autonomy of ontological principles in the effort to systematize the diversity of nature in terms of morphology; a partial abandonment in the face of evolutionary data of the methodological principle of parsimony; a tendency to conceive of causal interrelations reductively rather than factorially; the theological argument that God " intervened " at the origin of every species; a respect for authority which has blunted the thrust of much of the traditional analyses. It is their cumulative and mutually reinforcing effect that is denoted in the expression, " the error of univocally ontologized kind-essences."
No one, in my reading, has better summarized the current and long-standing failure of traditional philosophy and contemporary biology to communicate in the area of species--notwithstanding their common logic and common set of questions, formally speaking--than has Raymond Nogar.167 In a symposium on The Species Problem (1957), Nogar notes, Ernst Mayr, the editor, deplored the wide variety of species concepts and says:
I believe that the analysis of the species problem would be considerably advanced if we could penetrate through such empirical terms as phenotypic, morphological, genetic, phylogenetic, or biological to
166 For example, it does not seem possible to save all the theological texts of Aquinas if one admits that natural origin--i. e., origin in which the proportioned operation of secondary causes is undisturbed--applies below man even in the case of beings which differ in grades of being as well as in degrees of perfection. See The Problem of Species, pp. 226-30.
167 In The Wisdom of Evolution, pp. 328-30.
page 265
the underlying philosophical concepts. A deep and perhaps widening gulf has existed in recent decades between philosophy and empirical biology. It seems that the species problem is a topic where productive collaboration between the two fields is possible.168
Commenting on this text, Nogar considers Mayr's position to be perfectly correct. He then points out the obstacle to such collaboration that must first be overcome:
But the difficulty with the species problem is that the biologist and the philosopher are usually looking for different things. Hence the difference in the meaning of terms. The biologist is seeking a workable field definition of species which will enable him to classify all animals and plants. The philosopher, on the other hand, has been attempting to find a sic et non division of cosmic reality which will, by a single characteristic, manifest what a given natural species is and how it differs from every other natural species.169
The indispensable step, therefore, in achieving the collaboration Mayr calls for is that the philosopher put aside for the moment his preoccupation with discriminating between irreducible grades of being, in order to attend to the genetic and causal explanation of natural kinds secured by modern evolutionary science. At the level of individual substances as members of adaptive populations structured intrinsically through interaction, what are the " underlying philosophical concepts "? What is the ontological status of species so considered?
The question is proper and possible inasmuch as the ontological order bases all modes reality takes at every existential level. It is necessary if the real nature of Darwin's influence on philosophy is to be made explicit. And it is a distinctively contemporary question inasmuch as its answer is the basis for
168 Ernst Mayr, The Species Problem (Washington: American Association for the Advancement of Science, 1957), p. 11.
169 The Wisdom, of Evolution, p. 328: " The latter group has followed, in the main, the lead of the logician or dialectician who attempts to view things in their ideal perfections. The logician uses as his model the logical instrument invented in the early centuries called the Porphyrian tree after the Greek neo-Platonist Porphyry (A. D. 233-304). By means of this classic diagram, the world of reality is arranged according to an ideal bipartite division of being.
" It has been shown in great detail that nature and natural species cannot be viewed with this perfect logical or dialectical arrangement."
the prior possibility of integrating through their respective ramifications the traditional and contemporary species problematics.
It is useful in seeking to come to terms with this question to place ourselves explicitly in the evolutionary context, that is to say, in the context of history as structured causally, in order to bypass for now the preoccupation of certain temperaments with projecting the disproportion formally involved in the causal succession of complex from simple beings, and with introducing God into the development of nature.
The configuration of the living, as of any other, world depends from instant to instant on its last previous configuration and on how the immanent processes, the " laws " of nature, tend to act on any given configuration. Involved is historical causation, which includes everything that has ever happened and which is thus an inherently nonrepeatable accumulation. In application to evolution, these rather abstract considerations mean that the actual course of evolution is determined not only by its processes but also by the cumulative total of all previous events.170
Just as in the traditional problematic of species, so in this one, the philosophical problems raised by the causality involved resolve radically into the question of the reality or meaning behind the term essence (essentia) --but with a difference. In the traditional problematic, the species " has only intentional being, except as a constituent in the individual nature, through which it, too, participates in the act of existence," 171 inasmuch as the species " is that essence which can receive no further determinations except those of individuation." 172 " From this it will be clear that the word ' species,' " as used in the traditional problematic, " never refers to an existent thing, for in the domain of material beings only individuals exist, and never species." 173
170 George Gaylord Simpson, " The Study of Evolution: Methods and Present Status of Theory," in Behavior and Evolution, edited by Anne Roe and George Gaylord Simpson (New Haven: Yale, 1958), pp. 21-2.
171Adler, The Problem of Species, p. 19.
172 Ibid., p. 18.
173 Ibid., p. 14. See p. 88 of Simon, The Tradition of Natural Law (New York: Fordham, 1965), middle paragraph.
When we speak of two substances as belonging to the same species, we mean that they communicate in the same specific nature, though, of course, what is common to them is not identically the same in both, because the specific nature is differently individuated in each, according to the individual differences which constitute their twoness or numerical diversity. The specific nature they share in common is the same only in the sense indicated by the fact that a third substance of different species would differ specifically as well as individually from the two things first considered. The specific nature of the third would be different. In short, the fact that a specific nature can exist in its purity, i. e., in its absolute unity apart from individual multiplications and differentiations, in its unrestricted universality, only in an intellect which abstracts the form from the individuating conditions of matter, does not mean that " species " signifies only the concept (second intention) rather than that which is conceived (first intention). That which is conceived is the specific nature as an ontological principle, commonly present in a number of individuals which are truly apprehended as belonging to the same species. The potential universality of the specific nature,--a potentiality actualized only by intellectual abstraction,--is identical with the actual commonness of the nature as participated in by a number of individuals. Although apart from the mind, the specific natures of composite substances do not exist as universals, they do exist commonly,--i. e., as the same nature in two or more individuals,--and this fact is the ontological counterpart of the universality of the idea achieved by abstraction.174
In this new problematic, by contrast, " the species is constituted by a substance incorporated in a mass," and " the masses formed by these substances are not unitary entities but collective ones,"175 functioning entirely independently of our mental constructs in patterns of distribution conditioned by ecology or geography.
This indicates at once the altered sense of the term " essence " as it occurs in the two problematics: " If the word ' essence' be used to signify what is the proximate subject of the act of existence, then, in the case of composite substances,
174 Ibid., p. 13. See also John V. Bums, "The Problem of Specific Natures," The New Scholasticism, XXX (July, 1956), pp. 286-309.
175 Beaudry, art. cit., p. 225.
essence as the subject of existence must be the individual nature rather than the specific nature." 176 At the same time it also indicates, from the traditional viewpoint, the fundamental reason why species in the second or modern sense do not constitute an arbitrary schema nor circumscribe a reality too dark to be illumined in a properly ontological way: since, " in the case of composite substances, essence as the quiddity or principle of intelligibility, and essence as the proximate subject of existence, are not the same nature " 177 (the former being but potentially individuated, the latter actually so), and since in the case of natural populations " the distinctness of the individuals does not destroy the reality of the mass " 178 or " natural grouping," it stands out clearly that " the proper task for the philosopher, with respect to evolution, is primarily the analysis of the principles of substantial change, as bearing on the production of the unlike, both accidentally," or with respect to the diversification of superficial kinds, " and essentially," or with respect to the establishment of the radical kinds, " in the process of procreation." 179 Inasmuch as the latter is possible only in the light of the former, however, it is clear both that and how the two problematics require interarticulation, and it is just at that point that the celebrated " influence of Darwinism on philosophy " is felt.
This will suffice to indicate why and in what sense a hylomorphic analysis of the structure of interaction in terms of what can be said at the level of existence exercised and prior to any analysis of the pure line of essence taken in itself (whereon alone arise the questions about the constitution, order, and number of radically distinct kinds) is the region of mediation between the primary concerns of the differently oriented species problematics of traditional philosophy and contemporary science. We may turn at once to the delineation of this region.
176 Adler, The Problem of Species, p. 18.
177 Ibid., fn. 6, p. 18.
178 Beaudry, p. 225.
179 The Problem of Species, p. 274, fn. 284. See fns. 156 and 157 supra.
page 269
That which makes a thing to be what it is, or, more precisely, that by which a thing is such a thing as it is ("id quo ens est tale "), is said to be its essence.180 Such a characterization, however, never signifies at the level of first intention (of " the organism as a describable object") a class of objects, but rather does it signify essence as the inward condition of the fact of this concrete existent. Here then, for our purposes, is the starting point from which alone must be determined the primary meaning of essentia, i. e., the meaning to which all other essentialist notions must be derivatively referred. Precisely in attaining explicitly to this determination can we effect the destruction of essence as a specific kind-concept of univocal predication, thus clearing the way for the authentic influence of Darwin on philosophy and removing the obstacle to productive collaboration between modern biology and traditional philosophy at a single stroke.
Historically, we have already indicated a number of critical considerations relevant to this line of inquiry; without pretending to develop thoroughly the analysis required to complete the proposed destruction, we can sketch at least in an indicative, preliminary way the lines which it must follow if it is to be carried through successfully.
180 ". . . it is things, subjects, existents that we experience. From these existents our intelligence disengages by abstraction essences--' suchnesses' or intelligible ' structures'. These are the object of its first operation (simple apprehension) and of eidetic vision. Though these essences are found in a state of universality in our mind, where they are known as such, they exist really in things--in a state of singularity, as individual natures. To deny or to put in doubt this extramental reality of (individuated) essences would be to put in doubt the noetic value of the human intelligence. But for a sufficiently attentive analysis what is the absolutely precise and ' pure' data of the intelligence as far as essences are concerned? Because they are derived from existents by the operation of the intelligence, they do not appear as the existents themselves made present to us, but quite precisely as something immanent in the existents and which determine the existents to be what they are. The intelligence seizes them and gives them to us as that by which the things, subjects, or existents, are such or such. Hence, in its very notion, essence is a principle quo." Jacques Maritain The Degrees of Knowledge, pp. 435-6. Cf. A. G. Van Melsen, The Philosophy of Nature (Pittsburgh: Duquesne, 1961), " The Species--Individual Structure of Matter," pp. 115-125.
page 270
Fundamentally, the question evolution poses in terms of our understanding of essence is the question of being-as-possible: Essence within this existent as a subject capable of existing-actualized points to the question of how was this essence actualizable? What was its pre-subjective reality as such?
Here we must realize at once that in applying the concept of possibility at the level of essence so considered we make a transcendental transference, so that the meaning of our term becomes simply different from what it denoted at the existential level. We cannot ask about possible essences as such in terms of a determinate positive content, not even by limiting such a content to intelligibly prejacent " essential notes." In other words, in itself, essentia, as the capacity to be, cannot be conceptualized: as a potentiality or subject " out of which " and considered apart from actual existence or " esse," the word essence retains no intelligible content.
It is necessary to repeat in this connection that we are making no statement here concerning " the line of essence considered in itself," i. e., as an a priori of historical causation, which, precisely as a purely eidetic consideration, would pertain most properly to considerations of second intention (i. e., to phenomenological research and to logic), or derivatively and as a constitutional question, or question of formal intelligible constituent sine qua non, to metaphysics; we address ourselves rather and with full reflexive restriction to structured exercise of existence which is exactly the meaning of " essence " in terms directly and immediately of first intention.
It is for this very reason that our concern shares the intentional content of the traditional efforts at an elaboration of the sense of subsistere: " if existence is seized by the essence as act by potency, it is by (the existence) itself holding (not certainly [through] efficient causality, but by formal or intrinsically activating causality) the essence outside the realm of simple possibility, since the esse is not received by the essence as in a pre-existing subject which would thus already be in existential act. The essence which receives existence holds from it--in what concerns the existential order--absolutely all its
actuality, in short is nothing without it";181 from which it must be inferred that " since existence is by its very notion an exercised act, the essence can be so held outside the realm of simple possibility only on condition of being at the same time carried by subsistence to the state of subject or supposit capable of exercising existence." 182 Hence the conclusion: " the proper effect of subsistence ... is simply . . . the promotion onto a new plane of the incommunicability which defines singularity."183
It is not therefore just a matter of one metaphysical dimension in the structure of being but of the primordial dimension enclosing all others. By attempting to place ourselves ontologically at the level of natural kinds as such existing in order to " penetrate through such empirical terms as phenotypic, morphological, genetic, phylogenetic, or biological to the underlying philosophical concepts," we find ourselves at one and the same time located outside the order of essence considered in itself (the order of intelligible a priori for the possibility of a material order of being) and within a region of shared concern constituted by the pattern of interimplications between the traditional and the modem problematic of species, but a region
181 Jacques Maritain, " On the Notion of Subsistence: Further Elucidations," in Appendix IV to The Degrees of Knowledge, p. 437.
182 Ibid., p. 438.
183 Ibid.: " And so the proper effect of subsistence is not ... to confer on the individuated essence or individual nature an additional incommunicability (this time in relation to existence) or to make it limit, appropriate, or circumscribe to itself the existence it received, and hence prevent its communicating in existence with another essence or receiving existence conjointly with another essence: it is simply to place it in a state of exercising existence, with the incommunicability proper to the individual nature. The individual nature does not receive a new incommunicability from the fact of subsistence. Facing existence as a subject or supposit capable of exercising existence, it is enabled to transfer it into the existential order, to exercise in existence itself the incommunicability which characterizes it in the order of essence and as an individual nature distinct from any other. This is not a new kind of incommunicability, but the promotion onto a new plane of the incommunicability which defines singularity. Subsistence renders the essence (become supposit) capable of existing per se separatim (cf. Summa, III, q. 2, a. 2 ad 3), because it renders an individual nature (become supposit) capable of exercising existence."
till now undisclosed as shared from the standpoint of the primary concerns of either problematic. Herein we may suspect is a crucial area wherein not only are the evolutionary species reduced to their underlying ground of intelligible possibility but wherein also careful reflection upon the data of evolution opens the way to a decisive reformulation of a question " disputata inter doctores " for literally centuries. And just as the value of this former penetration frees the proper influence of Darwin on philosophy (an influence altogether different from what Dewey envisaged " in anticipating the direction of the transformations in philosophy to be wrought by the [putatively] Darwinian genetic and experimental logic " 184), so is the value of this latter reformulation inestimable to the Aristotelian philosophical tradition, for all will agree that--de jure at least-- " a problem (not a mystery) is the one thing which should not be perennial in philosophia perennis." 185
It appears, then, that subsistence constitutes a new metaphysical dimension, a positive actuation or perfection, but under the title of a state (according as a " state " is distinguished from a " nature " [i. e., specific nature au sens traditionelle]).... Let us say that the state in question is a state of active exercise, which by that very fact makes the essence pass beyond the order of essentiality (terminates it in this sense) and introduces it into the existential order--a state by reason of which the essence so completed faces existence not in order only to receive it, but to exercise it, and constitute henceforth a centre of existential and operative activity, a subject or supposit which exercises at once the substantial esse proper to it and the diverse accidental esse proper to the operation which it produces by its power or faculties.186
184 Dewey, " The Influence of Darwinism on Philosophy," p. 18.
185 Adler, "Solution of the Problem of Species," p. 341.
186 Maritain, " On the Notion of Subsistence," p. 438. See Etienne Gilson, Being and Some Philosophers (2nd ed., corrected and enlarged; Toronto: Pontifical Institute, 1952), p. 183: " Finite essences always entail both limitation and determination, because each of them is the formal delimitation of a possible being. Yet, if such a possible essence actually receives existence, it is a being, owing to its own act of existing, so that, even in the order of finite being, the primacy of existence still obtains. Its act of existing is what insures the unity of the thing. Matter, form, substance, accidents, operations, everything in it directly or indirectly shares in one and the same act of existing. And this is why the thing is both being and one. Existence is not what keeps elements apart, it is what blends them together as constituent elements of the same being. For the same reason, temporal existence is neither the ceaseless breaking up of eternity nor the perpetual parceling out of being; it is rather their progressive achievement through becoming."
Gilson considers that " this intrinsic dynamism of being necessarily entails a radical transformation of the Aristotelian conception of essences," inasmuch as Aristotle's metaphysics was a " dynamism of the form," deepened in its own line by Aquinas into a " dynamism of esse (to be)." 187 That indeed is why (there are theological reasons as well, but they are irrelevant for this context) subsistentia is a problem distinctive of Thomistic metaphysics. But it is extravagant, in my estimation, to say that with this development of a tradition in its own line " the whole philosophical outlook on reality at once became different." 188 And in the second place, so far as the
187 Gilson, Being and Some Philosophers, p. 185. See the discussion in footnote188 below.
188 Ibid. Extravagant declarations by historians in philosophy have the decided
tendency of transforming themselves in the minds of their hearers into
doctrinal
positions sure of themselves and of their power to renew everything.
Such has
been the distinct tendency among certain of the disciples of Gilson, who, seizing
upon the " dynamism of esse," no longer hesitate to conjecture the next
step in
" the direction in which the history and science of metaphysics will develop"
(W. E. Carlo, The Ultimate Reducibility of Essence to Existence in Existential
Metaphysics [The Hague: Martinus Nijhoff, 1966], p. 3).
So far as the history of metaphysics is concerned, the reduction of essence to existence may well mark the metaphysical writings of prominent authors, and if so, the " whole philosophical outlook on reality " does indeed become different; and we find ourselves, by an unexpected turn of history, re-established within a Suarezian metaphysics, this time " turned on its head," so that existence is no longer reduced to essence in the denial of their real distinction, but the reverse (much what happened to Hegel at the hands of Marx).
So far as the science of metaphysics is concerned, however, the primacy of esse over essentia which recognizes itself in Thomas for the first time clearly is exactly a clearer realization for philosophy of the principle of the primacy of act over potency, secured now at the level of existential act. It is in this sense and this sense alone that the Aristotelian " dynamism of form" becomes with Thomas a " dynamism of esse"; and between the doctrine of the ultimate subordination of essence to existence and that of the ultimate reducibility of the former to the latter lies all the difference between philosophical progress by way of development and philosophical progress by way of substitution. Fr. Gredt has stated the final reason for the possibility of conceiving philosophical progress in the former manner in lines which leave nothing to be desired in point of exactitude, and which have the further merit of bounding definitively the doctrinal sense of historians' proclamations concerning the transformations of the philosophical landscape one discovers (and they are there) in reading Aristotle through the Commentaria and Summae of Aquinas: " Philosophia aristotelico-thomistica essentialiter consistit in evolutione rigorose logica et consequenti doctrinae aristotelicae de potentia et actu. Haec doctrina ab Aristotele proposita, a S. Thoma declarata et ulterius evoluta, in schola thomistica iterum iterumque elaborata est et contra adversariorum impugnationes defensa. Fundameutum eius est distinctio realis inter actum et potentiam limitantem actum: inter essentiam limitantem esse et materiam limitantem formam. Esse irreceptum est simpliciter infinitum, actus purus; et forma pure spiritualis, in nulla materia receptibilis, est in sua linea infinita. Quo stabilitur distinctio inter Deum et mundum, inter mundum spiritualem et corporeum. . . . philosophiam aristotelico-thomisticam doctrinam ex hoc fundamento logica consequentia evolutam," ostendibile est. (J. Gredt, " Introductio" in Elementa Philosophiae Aristotelico-Thomisticae, Vol. I, p. 5, n. 3. See in this same line the instructive article by C. Fabro, " Tommaso d'Aquino," in Enciclopedia Cattolica, Vol. XII [Florence, 1954], cols. 259-265.) But then, everyone knows that Fr. Gredt is one of the " manualistae": see Jacques Maritain's remarks on " The Philosophy of St. Thomas " in The Peasant of the Garonne (New York: Holt, Rinehart, & Winston, 1968), pp. 135-141.
The point remains that one may have " progress " in philosophical history by substitution, by a discontinuous jumping between the fundamental dialectical options or " logical possibilities" envisionable in terms of a basic philosophical problem; but in the history of a doctrine (something else than a school), such " progress" has more of the character of a series of betrayals or abandonings, whatever may be the doctrinal position from which one views the movement. And one may quite well leave aside the language of the " real distinction" (esse/ essentia), still more the " texts " from whosesoever pen, without turning one's gaze from the matter-at-issue: what is the character of the difference between act and potency, and what does this imply in the order of lived experience for existence exercised?
See further fn. 196 below.
Aristotelian conception of essences was involved in the problem of specific natures, it neither was nor could be " radically transformed " without the whole problem of the metaphysical grades of being being abandoned. There is no doubt that, as Mortimer Adler has so carefully exhibited, this St. Thomas did not do. If he had done so, the " traditional" species problematic would not be distinguishable from the modern one in its primary concern. For St. Thomas, as for Aristotle, the notion of species was convertible with the usual use of essence and belonged to the ontology of natural kinds by way of secondary employment.
page 275
What is true is that the distinctive advance of St. Thomas over Aristotle in having recognized the transcendence of existence respecting essence makes it possible to see the repercussions of evolutionary species on the question of the hierarchy of being according to essential grades. But, without further historical digression, let us resume the thread of our analysis.
As we noted initially, a strict employment of the term essence is possible which confines us to the concrete real, the historical reality as reality, and refers simply to the capacity to be as a self-identity. The whole of that which constitutes a capacity to be, however, must include what is necessary, i. e., whatever is intrinsic: and since only individuals do or can exist, individuating characters are radically enclosed at the level of essence, not as " accidental " (per accidens) modifications but as intrinsic and absolute substantial modalities. The total " capacity to be" in every instance is not merely " forma substantialis " but " matter-form," or, more exactly (for this is what forma substantialis is), materia actuata, i. e., all individuating notes or modalities. " It is evident that every natural generation involves a measure of uncertainty. If that uncertainty could be entirely eliminated, it would be because the form would be entirely determined--but in that case generation itself would become impossible." 189 Since it is at the heart of being, this " incertitude " bears equally on the existence of the effect or product and on its very structure.
It is precisely the lack of determination of natural forms and their incapacity for individuating themselves which makes matter necessary for their existence. This necessity for matter introduces into the form itself an irreducible obscurity. There can be no idea of a cosmic form that is distinct and independent from the idea of the composite; 190 and the matter which enters into this idea is not determined at all without signifying also a determinability with respect to an infinity of other forms. A non-subsistent form is not a quiddity in the strict sense.191 This means that the different
189 De Koninck, " Refléxions sur le problème de l'indéterminisme," p. 238.
190 John of St. Thomas, Cursus Theologicus, II, p. 575, n. 15.
191 "Anima sensibilis cum non sit res subsistens, non est quidditas, sicut nec aliae formae materiales, sed est pars quidditatis, et esse suum est in concretione ad materiam." (St. Thomas, de Potentia, q. 3, a. 2 ad 2).
natural forms (I do not say the diverse ones) cannot be absolutely opposed as if they were forms of pure spirits, because their definition embraces the notion of matter, that is to say, the possibility of an infinity of other forms which can be drawn out of this matter. Consequently the existing varieties of forms or " natural kinds " are analogues of the segments of a continuum determined a-posteriori. In this sense they are contingent and always quidditatively new. Between any two given forms in nature, there is an indefinite possibility of other forms. These forms are in the matter in a purely potential manner; and consequently the determination which any material form is, is something to be constituted as determination. It is necessary to speak in this way if one wishes to avoid the latitatio formarum (the actual latency of forms) .192
Therefore, at the level of the concrete real, of first intention, the actuality which is " esse " cannot reflect a univocal kind or type of being.193 The most radical and accordingly primary meaning which attaches to essentia is not " this kind" but " this existent"--that is, the fundamental notion in the term essence is one of proportion: essentia dicitur primo et per se ' proportio ad esse' (" essence bespeaks primarily and of itself a proportion to existence " 194). And since there can be as such no proportion at the level of being-as-possible, the question of possible being becomes a question of how an existential proportionality is effected. Thus, we speak of " possible being " rather than of " the possibility to be " precisely because things come to be only as individuals, but the phrase may still be misconstrued.
Essences are often conceived as possible beings, the reality of which coincides with their very possibility. But we should be careful to distinguish between essential possibility and existential possibility. For, indeed, they belong in two distinct metaphysical orders, so much so that there is no way for us to reach the second one
192 De Koninck, pp. 233-4.
193 Cf. Gilson, Being and Some Philosophers, pp. 185-6. Adler, " Solution of the Problem of Species," pp. 356-7.
194 Cf. Anthony Schillaci, O. P., De passibilitate entis finiti (Mimeographed: Fall, 1961), p. 3: " Possibilitas entis non limitatur nisi per intrinsecam contradictionem. . . . Possibilitas intrinseca alicujus entis identificatur cum eius essentia, cum intrinseca possibilitas nil aliud sit nisi aptitudo rei ad esse subjectum tou 'esse', quae est ratio constitutiva alicujus rei in ratione essentiae."
through the first one. An essence is possible, qua essence, when all its determining predicates are compossible. If they are, the existence of the corresponding being is possible; if they are not, it is not. And this is true, but it is true only in the order of essential possibility, not at all in the order of existential possibility. Many metaphysicians seem to imagine that an essence cannot exist, so long as it has not received all its determinations, that, as soon as it has received them, it is bound either to burst into existence or, at least, to receive it. Now a twofold error is responsible for such an illusion. The first one is not to see that to be fully completed in the order of essentiality does not bring an essence one inch nearer actual existence. A completely perfected possibility still remains a pure possibility. The second error is to forget that the essence of a possible being necessarily includes the possible existence through which alone it can achieve its essential determination. To repeat, essential possibility is no sufficient reason for existential possibility, and since its essence is what a being is going to become, if it exists, existence itself necessarily enters the calculation of its essential possibility.195
It follows ineluctably that only on the basis of causality--a basis very different from that provided by any phenomenological eidetics--can essentia be understood in the most fundamental manner, i. e., as a proportio ad esse.196 The question of the actuability of essence, of the reality-status of being-as-possible, cannot be dealt with except in terms of the pre-existence of effects in their causes:197 an answer framed with
195 Gilson, Being and Some Philosophers, pp. 182-3, my emphasis.
196 Maritain contends that " the very distinction between existence as received and existence as exercised, is understandable only in the light of the axiom causae ad invicem sunt causae." " This involution of causes is at the core of the problem." (" On the Notion of Subsistence," p. 439). Gilson is in agreement that the involution of the causes is at the core of the problem, but he seems to conceive their play somewhat differently than does Maritain. (See Being and Some Philosophers, p. 172, in contrast with The Degrees of Knowledge, p. 437). William Carlo in a recent book seems to be of the opinion that the reciprocity of the causes is outside the central issue (The Ultimate Reducibility of Essence to Existence in Existential Metaphysics, esp. pp. 20-22). In this last perspective, I, for one, lose sight entirely of the traditional species problematic.
197 Gilson, Being and Some Philosophers, pp. 210-11, makes some striking observations in this connection (observations, moreover, which sound quite like Bergson: cf. " The Possible and the Real," in Bergson's The Creative Mind, New York: Philosophical Library, 1946, pp. 91-106): " Having overlooked the transcendence of existence, essentialism has entertained the curious illusion that, since, in order to be, a being must at least be possible, the root of being lies in its possibility. But possibility is a word of several meanings. It may mean the simple absence of inner contradiction in an essence, and, in such cases, all non-contradictory combinations of essences are equally possible, but none of them is one step nearer its actualization than another one. It may also mean that an essence is fully determined, so that it is actually capable of existing. Such possibles are in the condition which Scholastics would have called that of proximate potency to existence. But such a possibility still remains pure abstract possibility. Is it true to say, with so many philosophers, that, when all the conditions required for the possibility of a thing are fulfilled, the thing itself is bound to exist? Scarcely. When all those conditions are fulfilled, what is thereby fulfilled is the possibility of the thing. If any one of them were lacking, the thing would be impossible, but, from the fact that all those conditions are given, it does not follow that the thing is required to exist. The possibility of its essence does not include that of its existence, unless, of course, we count among its required conditions the very existence of its cause. But, if we do, the being of the cause is the reason why the possible is a possible being. Omne ens ex ente: all being comes from another being, that is, not from a possible, but from an existent.
" To overlook this fact is completely to reverse the actual relation of essences to existences. In human experience, at least, there are no such things as fully determined essences prior to their existential actualization. Their esse is a necessary prerequisite to the fullness of their determination."
page 278
any other reference and put forward as fundamental posits implicitly the equivalent of a Platonic Idea. Indeed, it was the consideration of essence primarily as the focus of formal perfections, to the neglect of interrogating it (except in a secondary fashion) as the existentially established possibility for concrete presence in the world, that led thinkers into paradox and contradiction before the evolutionary species problematic.
But the irrepressible essentialism of the human mind blinds us to that evidence. Instead of accounting for potency by act, we account for act by potency. We rather forget that what is at stake is neither existence nor essence, but being, which is both. We fancy that essences, which owe their complete determination to existence, are eternally independent of existence. Everything then proceeds as though the essences of possible beings had been eternally conceived, by a divine mind, apart from the very act through which they would some day become actual beings. Thus conceived, existence does not enter the concrete determination of essences; it fills them up.198
198 lbid., p. 211. Cf. Joseph Owens, " The Intelligibility of Being," Gregorianum, XXXVI (1955), pp. 169-193.
In this regard we may appropriate (I do not say " concur with ") some critical reflections put forward by Heidegger.199 " In connection with all the determinations of being and the distinctions we have mentioned, we must bear one thing in mind: because being is initially physis, the power that emerges and discloses, it discloses itself as eidos and idea. This interpretation never rests exclusively or even primarily on philosophical exegesis." [" The existence of nature is known directly (per se) insofar as natural things are manifest to the senses. But what the nature of each particular thing is, or what the principle of motion is, is not manifest." 200] " Appearance, doxa, is not something besides being and unconcealment; it belongs to unconcealment." Thus " it cannot be denied that the interpretation of being as idea [Lat., species vel forma] results from the basic experience of being as physis. It is, as we say, a necessary consequence of the essence of being as emerging Scheinen (seeming, appearing, radiance)....[" Esse objective enim consistit in ipsa orientatione per modum transcendentalem ad esse subjective."] But if the essential consequence is raised to the level of the essence itself and takes the place of the essence, what then?. . . . The crux of the matter is not that physis should have been characterized as idea but that idea should have become the sole and decisive interpretation of being." " Physis is the emerging power, the standing-there-in-itself, stability." [" Because everything acts insofar as it is an
199 From M. Heidegger, An Introduction To Metaphysics, trans, by Ralph Manheim (New York: Anchor, 1961), pp. 165, 160, 152, 153, 165, 154-5, and 153-4, respectively: Heidegger's own emphases. However, let there be no misunderstanding here. Anyone who has genuinely grasped the implications of the phenomenological " Sachen selbst" and the research they in principle ground will realize how radical our appropriation shall have to be in order to place any formally philosophical reflections of Heidegger in an other than phenomenological context. Lest the reader suspect we are passing over with inadequate assessment the immense difficulties such an appropriation claims to have overcome, we refer him to our study which takes up the issue with attention to detail: " The Situation of Heidegger in the Tradition of Christian Philosophy," The Thomist, XXXI (April, 1967), pp. 159-244, esp. sec. VII, "Phenomenology: The Medium of the Being-question," pp. 222-236. A full length book on this question is in preparation.
200 St. Thomas Aquinas, In II Phys., lect. 1, n. 8.
actual being, the consequence is that everything stands in the same relation to action as it does to being." Thus " the measure and quality of a thing's power is judged from the manner and type of its operation, and its power, in turn, manifests its nature; for a thing's natural aptitude for operation follows upon its actual possession of a certain kind of nature." 201] " Idea, appearance as what is seen, is a determination of the stable insofar and only insofar as it encounters vision." [Thus, not only is it true that " of no thing whatever can a perfect knowledge be obtained unless its operation is known," but we must also take account of the critical factor that " we do not know a great many of the properties of sensible things, and in most cases we are not able to discover fully the natures of those properties that we apprehend by sense." 202] Hence " being itself, interpreted as idea, brings with a relation to the prototypical, the exemplary, the ought." " From the standpoint of the idea, appearing now takes on a new meaning. What appears--the phenomenon--is no longer physis, the emerging power, nor is it the self-manifestation of the appearance; no, appearing is now the emergence of the copy. Since the copy never equals its prototype, what appears is mere appearance, actually an illusion, a deficiency. Now the on becomes distinct from the phainomenon. And this development brings with it still another vital consequence. Because the actual repository of being is the idea and this is the prototype, all disclosure of being must aim at assimilation to the model, accommodation to the idea. The truth of physis, aletheia as the unconcealment that is the essence of the emerging power, now becomes homoiosis and mimesis, assimilation and accommodation, orientation by . . ., it becomes a correctness of vision, of apprehension as representation." " The idea, as the
201 St. Thomas Aquinas, Summa Theologiae, III, q. 77, a. 3; and Summa contra gentiles, II, c. 1, n. 1: respectively.
202 Summa contra gentiles, II, c. 1, n. 1; and I, c. 3, n. 5: respectively. In the Collationes de Credo in Deum, a. 1, is the interesting remark that " our knowledge is so imperfect that no philosopher has ever been able to discover perfectly the nature of a single fly."
appearance of the essent, came to constitute its what. Thereby the whatness, the ' essence,' i. e., the concept of essence, also became ambiguous." [Thus, in many traditional writings, " In its proper intelligibility, form bespeaks a capacity for realization (dicit realizabilitatem) in any time, place, or subject whatever; and consequently, prior to existence, the essence itself of a thing is a possibility indifferent to existing in any particular time, place, or set of external circumstances (in quavis contingentia extrinseca)."] Such has been the historical interpretive consequence of according primary import to that which is secondary in the notion of finite being.
In terms of the actually existing things in the world, this is not to say that classification into kinds is fictitious, altogether false, but that such classification is shot through with analogy --and this is exactly what genetics has disclosed in a researchable manner. There are natural units, concrete universals, as it were, corresponding to the term " species." There are, that is to say, groups of individuals structured basically through sexual behavior so that the absolute range of adaptive tolerance of the members of any given group is closely coincident, yet divergent relative to the adaptive area of other groups; but within these interaction-structured groupings, within any given species, individuality is not a reducible phenomenon, neither genetically nor metaphysically, so that typological thinking (however useful it may be for certain purposes) remains of itself at the level of second intention, one step removed from the concrete real. In terms of the proportion to " esse," there can be no incidental (" per accidens") differences, " for even though a thing's existence is other than its essence, existence is not to be understood as something added over and above the essence after the manner of an accident but as if established as the result of the principles of the essence. And for that reason the term being, which is applied to a thing by reason of its very existence, signifies the same total reality as the term which is applied to a thing by reason of its essence." 203
203 St. Thomas Aquinas, In IV Met., lect. 2, n. 558.
In its complete explication the analysis of essence at the level of possible being (to which the evolutionary problematic forces philosophy) gives full metaphysical consistency to the notion of " being in and through a world." Space-time modifies and enters into the reality termed essence precisely in that there is no parent engendering progeny in a one-to-one relationship (there is no causal process in nature reducible to the transmission of an identical form); rather, there is only and always parent plus this proximally circumscribing environment, together establishing the extrinsic though immediate proportion constituting this individual existingly.
A " possible being " thus understood is in no degree virtual, something ideally pre-existent. A simple absence of external hindrance and non-contradictoriness of intrinsically constitutive notes is alone signified, together with an actual convergence of causes adequate--be it by reason of nature and chance or nature and art--to the production of a corruption (which is to say a generation: corruptio unius est generatio alterius inquantum materia prima numquam existit per se) in the world of nature. (To borrow an illustration from William Howells: " Man himself could only appear when a very high organization had been attained [absence of external hindrance]. For hands and a big brain would not have made a fish human; they would only have made a fish impossible [contradictoriness of intrinsically constitutive notes.] [While from the standpoint of an actual convergence of causes in the history of life,] man's own trail, among the many trails in evolution, was well defined: he had to be a mammal and he had to be a primate." 204) In a crude though preliminary way--" there is at least a poetic anticipation here," Adler contends, " of recent scientific discoveries concerning the causal efficiency of various types of radiation to produce mutations in the germ plasm " 205--this was hinted at by Aristotle: " Man is begotten by man and by the sun as well." 206 What Heidegger remarks concerning
204 Mankind in the Making (Garden City, New York: Doubleday & Co., 1959), p. 341.
205 Adler, The Problem of Species, p. 229.
206 Physics, II, c. 2, 194b13f. Cf. St. Thomas, In IV Met., lect. 3, n. 785.
our awareness of beings holds equally as regards their proper existence: " It is through world that the essent first becomes essent." 207
Thus, " to be " means " to stand within limits "; while to stand within limits means to exist as a dialectically conditioned possibility or aspect of a world: essence is only the potential dimension of contingent substance which defines it and fits it into a given population and environment according to certain active and passive capacities, while correlatively existence is essence simultaneously determined as identity with itself and reference to another, scil., the environmental world.
One would have a perfect necessity in the works of nature therefore only if one would make abstraction from the matter---principle at once of individuation and contingency--which enters into every work of nature and without which nature would not be nature. And when we speak of the " hypothetical necessity " of natural laws we mean to say that an effect is certain to the extent that form prevails over matter [actual determination over possible determination otherwise]. In other words, the laws of nature would be necessary if matter were neither nature nor principle of contingency, if in the work of nature, nature were form alone. The expression " hypothetically necessary " is therefore subject to ready misunderstanding. It does not at all apply to future contingents, except in their relation to a divine intelligence and will.208
" The organism and the environment," Dobzhansky notes simply, " are really parts of an interacting system." 209
207 An Introduction to Metaphysics, p. 51.
208 De Koninck, p. 240.
209 Mankind Evolving, p. 89. Gardner Murphy, Director of Research at the Menninger Foundation, applies this view directly to the understanding of the human phenomenon as such: " we often look for human nature in the wrong place; we merely look inside the living system. [Yet] any products whatever which life yields, are in a sense the products of a system of events deployed through a vast system of forces. Indeed, life can be destroyed and any given avenue can be blocked, but to find the wellsprings of human nature by looking inside the capsule is to miss the field character of the event." " A Platonic idea of intrinsic human nature as something guiding human destiny . . . needs the benefit of field theory to achieve coherence and credibility in an era in which both man and his environment need to be seen not as two realities but as two phases of one reality "-- human nature. " From such a point of view, part of the essential nature of humanness lies in the specific evolutionary trends that underlie the many demands of mankind upon life. . . ." (Human Potentialities, pp. 325, 307, and 37, respectively. See also pp. 23-4, 109-10, 177, 251-2, 270, 283, 287, 298-301). Johannes Messner, on a solidly and explicitly Thomistic basis, arrives at a similar formulation: " In the first edition of this work the matter was dealt with in the following way: Society is an accident, requiring a substance, namely, man, to support it, but an ontological accident, since man is by his nature a social being. . . . Today we would say that ontologically and metaphysically, if the expressions substance and accident are given the meaning just set down, society can only be described as an accident. It seems, however, to be another question whether the special supra-individual reality of society can be fully explained in terms of these disjunctive concepts of substance and of accident, so conceived. Certainly society is not a substance in the sense of subsisting in and for itself, independently of individuals. Yet, although society is not a substance in this sense, we cannot conclude that its being in the ontological and metaphysical sense is merely secondary in relation to the individual as such." On the contrary, " since the idea of evolution is inseparable from the nature and the natural law of man," Messner is driven to conclude that " society and the individual possess, ontologically and metaphysically, equally original being. Neither can be derived from the other or reduced to the other as the primary being. . . . The association of individuals in society indeed consists in interrelations, but not in interrelations of integrated individuals . . .; rather, it consists in interrelations through which the individuals achieve full humanity and through which, therefore, a new reality is established." (Social Ethics: Natural Law in the Western World, J. J. Doherty, trans. St. Louis: B. Herder Book Co., 1965, pp. 106 f., 76, and 108, respectively, emphasis supplied. See also pp. 36, 55, 63, 76, 84, 97, 117-121, 124, 127, 132, 139, 142. See also Erik H. Erikson, " Evolution and Ego," Insight and Responsibility (New York: W. W. Norton & Co., 1964), pp. 134-157, esp. 152 f. Indeed, mused Alexis Carrel, " it would be absurd if external reality were incapable of encompassing man in his totality. It would also be absurd if its structure did not correspond in some measure to our own. It is thus reasonable to attribute the same objectivity to the world of spirit as to the world of matter." (Reflections on Life [New York: Hawthorn Books, Inc, 1965], p. 165). In these terms, it becomes impossible to define the end for man as man without ipso facto defining the end (and thereby the direction) of the evolutionary process which man extends.
In summary: possible being does not differ from actual being simply by the difference of an efficient cause, by a merely extrinsic principle. Rather, the root meaning of essence must be derived in terms of possible being as the causal establishment of a proportion to existence, so that at the level of the concrete real, of actually existing things, essence always involves the concretion of all space-time factors (among which the generator is primary but never exclusive) entering into the initial establishment of individuality; " there could be nothing
page 285
outside the essence of being which could constitute a particular species of being by adding to being; for what is outside of being is nothing, and this cannot be a differentiating factor." 210 Thus, at the level of first intention, all specific kind-concepts of universal predication--essentiae specificae--are and can only be media of analogous intelligibility.211 To make more of them than this is to confuse linguistic or logical and ontological classifications. Indeed, even in the traditional species problematic where it is irreducible grades of being which are at issue more than the existential diversity of kinds:
The unity of a nature as existing in many individuals is an analogical, not a univocal, unity of being, even though the concept whereby that nature is apprehended is primarily a univocal and not an analogical concept. This must be so, for there is no way in which the one can exist in the many except analogically.212
" No middle can be found," stressed St. Thomas, " between singulars and their species," for the very good reason that " actions have to do with singular things and all processes of generation belong to singular things ": " Universals are generated only accidentally when singular things are generated," i. e., they are consequent only on the consideration of reason, so that, although derived from the things, they are as qualitative universals extraneous to the individual natures which transobjectively ground them in the natural articulations and interaction-structured groupings of the environmental world.213
210 St. Thomas, In V Met., lect. 9, n. 889.
211 Cf. Adler, " Solution of the Problem of Species," pp. 356-7.
212 Ibid., p. 306, fn. 44 ad finem.
213 St. Thomas, In I Post. Anal., lect. 2, n. 21; In Met., I, lect. 1, n. 21; VII, lect. 7, n. 1422; and esp. IV, lect. 4, n. 574, respectively. Also Summa, I, q. 13, a. 12 ad 3; and q. 85, a. 2 ad 2. Thus the conception of the " concrete universal " (as we have used the phrase in this analytic) differs from the qualitative universal familiar to the logician not by way of negation or rejection but by going beyond the static conceptions of, e. g., " horseness," " whiteness," etc., to include explicit reference to the immediate phantasmal ground of conceptualization so as to sustain analogical eidetic visualizations in which singulars are seen as structured by and holding together through interaction, as well as in their formal and qualitative isolation: the idea constantly remains within its totality. Unlike the abstract universal which prescinds from existence in order to unite its subordinates in the perfect unity of an identical " quiddity," the " concrete " universal takes existence as the basis for an analogous predication concerning individuals of a specific interaction grouping. In brief, the concrete universal is a general notion, identical with the whole of the individuals from which we obtain it. Such a conception seems to derive its fundamental possibility from the type of analogical predication referred to traditionally as " analogy of inequality " or (more precisely) " analogy on the part of the things judged, but not on the part of the concept predicated." Cf. Adler, " Solution of the Problem of Species," pp. 356 ff. St. Thomas, In I Sent., d. 19, q. 5, a. 2 ad 1. Cajetan, De nominum analogia, cap. 1; Summa, I-II, q. 66, a. 1 ad 1.
In a similar view, Charles De Koninck comments: " C'est que tout concept formellement scientifique est fondé sur une induction incomplète indéfiniment perfectible--I'inductio per descensum ne peut jamais rejoindre l'expérience au point de fermer le concept et d'en faire un universel proprement dit: sa genèse même n'est jamais terminée." (Art. cit., p. 397). Cf. further R. G. Collingwood, Speculum Mentis (London: Oxford, 1924), pp. 220-221.
page 286
That which makes this thing to be what it is, is not an instanced universal or essential form but a unique, incommunicable, unrepeatable (i.e., historical] proportion to being-in-the-universe --which is something much finer!
That the appearance of a vegetable or animal species is due to specific causes, nobody will gainsay. But this can only mean that if, after the fact, we could know these causes in detail, we could explain by them the form that has been produced; foreseeing the form is out of the question. It may perhaps be said that the form could be foreseen if we could know, in all their details, the conditions under which it will be produced. But these conditions are built into it and are part and parcel of its being; they are peculiar to that phase of its history in which life finds itself at the moment of producing the form: how could we know beforehand a situation that is unique of its kind, that has never yet occurred and will never occur again? Of the future, only that is foreseen which is like the past or can be made up again with elements like those of the past. . . . But an original situation, which imparts something of its own originality to its elements, that is to say, to the partial views that are taken of it, how can such a situation be pictured as given before it is actually produced? All that can be said is that, once produced, it will be explained by the elements that analysis will then carve out of it. Now, what is true of the production of a new species is also true of the production of a new individual and, more generally, of any moment of any living form.214
214 Bergson, Creative Evolution, pp. 32 f., emphasis supplied. Cf. Bergson, " The Possible and the Real," The Creative Mind, M. L. Andison, trans. (New York: Wisdom Library, 1946), pp. 91 ff., esp. 99-104.
Within this strictly delimited context, then, we may appropriate this striking formulation of Bergson; Evolution " creates, as it goes on, not only the forms of life, but the ideas that will enable the intellect to understand it, the terms which will serve to express it. That is to say that its future overflows its present, and cannot be sketched out therein in an idea." 215 It does but express the necessary consequence of the realization that the natural kinds, such as " the class of Birds and the class of Fishes," can be distinguished only by means of characters rooted in certain dispositions of matter, of " properties " which are of the composite and never (even as signs) of the form alone; and cannot be the subject of a notion strictly speaking abstract, or of a definition in the logico-metaphysical sense-- the necessary consequence, as De Koninck says, of the distinctively modem and even Darwinian discovery that, so far as the structures of existence in time go, " the problem of contingency in nature is not limited to questions of chance and fortune, even if these two forms of contingency are the most evident"; for the very forms themselves which articulate nature have a fixity which is only feigned.216
It is the insufficient determination within the various grades of nature which makes possible events which go beyond even the limits of a specific natural grade, so that the contingency proper to chance presupposes a contingency, a mutabilitas in the natural cause. Whatever might be the perfection of its form, there ever remains in the composite a margin of indetermination which exceeds the formal determinations, and which constitutes the possibility of that form either falling short of its full realization, or producing an effect in nowise predetermined in either universal or particular nature (since this margin exists for the whole of nature as well).217
One sees thus in what sense we can speak of the creation of possibles. (Obviously, creation is taken in a very broad sense.) And this idea applies not only to chance and fortune, but to the nature itself. We have already explained that the infrahuman cosmic species are not absolutely determined as regards their structure,
215 Creative Evolution, p. 114.
216 De Koninck, art. cit., p. 235.
217 Ibid., pp. 241-2.
page 288
nor consequently true a-priori. Each natural kind is new in its structure. Once established, it constitutes a determined point of departure for other species in which the determination of their source and stem will in a certain fashion be prolonged: this determination has opened the world to essential structurations which would not have been determinately possible without it.218
Hence the need for never ending research, the danger of deductive postulations concerning the fulfillments of nature: " As a thing stands with regard to being, so does it stand with regard to truth. For the truth of those things which do not always stand in the same relation to being is not unaffected by change," since indeed " reality is not referred to knowledge but the reverse." 219
These considerations make it possible, I think, to see that the morass of philosophical perplexities in post-Darwinian thought are due to a certain ambivalence and equivocation in the species problematic of traditional philosophy, which ambiguity the rise of evolutionary science served to underscore and make unmistakable. At the same time, by disengaging the philosophical concepts underlying the species problematic of modern biology, these considerations also make it clear that evolutionary science has not altered the structure of the question of essential natures or kinds as the metaphysician poses it, although evolutionary science has made it clear that none of the natural kinds --oysters, butterflies, elephants, eels--are so constituted causally as to correspond to the infima seu atoma species, the " indivisible kinds," of which traditional philosophy so long spoke. Since there is no evidence that any ecological population as such is differentiated by a single formal property, and vast evidence that none is so constituted, it is a violation of the principle of parsimony to insist that any of the typical populations
218 Ibid., pp. 251-2.
219 St. Thomas, In Met., II, lect. 2, n. 298; and V, lect. 9, n. 896, respectively. (See also n. 895). Cf. Alexis Carrel, Reflections on Life, p. 60; Man the Unknown (Harper & Bros., 1939), p. 321; Pierre Teilhard de Chardin, The Phenomenon of Man, pp. 273 ff.; Gardner Murphy, " Man-World Relations," Human Potentialities, pp. 21 ft.; G. H. Mead, Mind, Self, and Society (Chicago: University of Chicago Press, 1934), pp. 203 ff.
we readily distinguish differ as populations according to the mode termed " radical " or (traditionally) " specific." If we choose to use as our primary reference for the term species " the natural groups afforded by the instincts of mankind," as Aristotle put it, or " the categories of science illumined by philosophic knowledge" of which Maritain and Maquart speak,220 then it is impossible to retain the notion of specific natures as being convertible with metaphysical essences without disastrous confusion and an adventure in myth-making. We must rather acknowledge forthrightly that the hierarchy of essences does not correspond to nor reveal the disposition of species.
Whether the disposition of species reveals anything about the hierarchy of essences--perhaps that it does not, after all, exist --even though the former cannot correspond to the latter, is our final question. In other words, the relation of evolutionary species to the philosophical doctrine of the immutability of essence, the question of " the influence of Darwinism on philosophy," of the mutual interimplications of the respective primary concerns of the traditional and the modern species problematics, can now be seen to come down to this: once the notion of species as genetic populations has been laid bare in its ontological ground, does the notion of species as essential kinds (i. e., kinds related in such a way that each substance of a given specific nature has an essential or radically constitutive perfection lacked by its proximate inferior in specific nature, and lacks an essential perfection possessed by its proximate superior in specific nature; so that, since the whole essential difference between essentially distinct kinds lies in the diversity of their substantial forms as rendered diverse by virtue of a positive and negative difference rooted in a common perfection, essentially distinct kinds as essentially distinct must be ordered in a perfectly ordered series or unilinear hierarchy in which: a] each member has a unique position, b] there is no coordination or equality of rank, and c] each member comes
220 See F.-X. Maquart, Elementa Philosophiae, Tomus II, Philosophia naturalis (Paris: Blot, 1937), esp. pp. 12-16.
page 290
before or after another in the ascending or descending scale of being) --does this notion retain any explanatory power at all? Or does it, like the notion of the infima species, belong to the historian of ideas and the category of philosophical myth?
Granted that the traditional and modern species problematics are and have been shown to be diverse in orientation, do their secondary implications illumine or contravene one another?
Since the traditional species problematic is inextricably bound up with the question of a natural hierarchy, it will be easy to engage it in the implications of the modern species problematic if we can show that the modern problematic as well implies inescapably a natural hierarchy. Once this has been shown, we will be in a position to judge whether the implications of the two problematics are contrary or mutually illuminating. The question of the influence of Darwinism on philosophy thus turns out to be simultaneously the question of the influence of philosophy--traditional philosophy at that--on Darwinism. It is the problem of the two hierarchies.
Let us move to a position where it comes into view.
VII. The Operational Displacement of Typological Thought in its Implications for Hierarchy.
Against the immediate background provided by this preliminary philosophical analytic and before attempting a concluding summarization of the eidetic character of organic evolution in terms of hierarchy, we must mention one other significant component of the development in this century of the science of genetics (not paleontology, as philosophers often assert) as the foundation of evolutionary explanations.
We have already seen how all explanation which accounts for reasons of being must pattern itself on a factorial conception of causality. To the extent that one or more of the four factors is unaccounted for, the explanation remains incomplete. It is possible, however, to attempt an explanation in terms of a reductive rather than factorial conception of causality, and such reductive explanations may take either of two forms. The
more important mode of reductive analysis is that which was first given expression by the Pythagoreans and the astronomers of the Academy, later taken up again by Galileo, Descartes, and Newton and subsequently extended in our own time into a universal science of nature. This is the " explanatory" method of mathematical-physics, a science which knows the real only by transposing it and not as the physical real, since it captures in things only that kind of formal cause which is the conformity of phenomena to mathematical law, and which is the basis of prediction and control inasmuch as the intelligible necessities susceptible to mathematical formulation are transcendent to the sensible object as such and insofar indifferent to its existential status. In itself, this method of converting a physical into a mathematical description constitutes a marvelous and exceptional instrument of natural science in its efforts to assign reasons for being; and so employed, it need not be a reductive explanation.
Since, however, knowledge formulated in the physico-mathematical pattern is formally and specifically distinct in its mode of definition from knowledge formulated in the philosophical pattern of " causes," there is always the danger that the instrument will be taken for an explanatory scheme in the full sense, and at once we are in the line of a reductive conception of causality.220a
220a J. Schwartz observes that " in its relations with science mathematics depends on an intellectual effort outside of mathematics for the crucial specification of the approximation which mathematics is to take literally." " The literal-mindedness of mathematics thus makes it essential, if mathematics is to be used correctly in science, that the assumptions upon which mathematics is to elaborate be correctly chosen from a larger point of view, invisible to mathematics itself. The single-mindedness of mathematics reinforces this conclusion. Mathematics is able to deal successfully only with the simplest situations, more precisely, with a complex situation only to the extent that rare good fortune makes this complex situation hinge upon a few dominant simple factors. Beyond the well-traversed path, mathematics loses its bearings in a jungle of unnamed special functions and impenetrable combinatorial particularities. Thus, the mathematical technique can only reach far if it starts from a point close to the simple essentials of a problem which has simple essentials. That form of wisdom which is the opposite of single-mindedness, the ability to keep many threads in hand, to draw for an argument from many disparate sources, is quite foreign to mathematics." " Related to this
deficiency of mathematics, and perhaps more productive of rueful consequence, is the simple-mindedness of mathematics--its willingness, like that of a computing machine, to elaborate upon any idea, however absurd; to dress scientific brilliancies and scientific absurdities alike in the impressive uniform of formulae and theorems. Unfortunately, however, an absurdity in uniform is far more persuasive than an absurdity unclad. The very fact that a theory appears in mathematical form . . . somehow makes us more ready to take it seriously. And the mathematical-intellectual effort of applying the theorem fixes in us the particular point of view of the theory with which we deal, making us blind to whatever appears neither as a dependent nor as an independent parameter in its mathematical formulation." (" The Pernicious Influence of Mathematics on Science," in Logic, Methodology and Philosophy of Science, ed. by Ernest Nagel, Patrick Suppes, and Alfred Tarski, Stanford: The University Press, 1962, pp. 356-8, passim. See Thomas Aquinas, In libros Aristotelis de caelo et mundo expositio, Bk. I, lect. 3, n. 24; and Bk. Ill, lect. 3, n. 560. Also fn. 70 in Part I of Nogar and Deely, The Problem of Evolution).
page 292
The only other way to fall into reductive explanations is to simply fail to see that the analysis of structure and function in nature always involves four correlated aspects, composition and organization as correlates of structure, agencies and products as correlates of function. Thus, for example, just as we cannot describe an organism except by telling what its parts are made out of and indicating how these parts are put together to form the whole, so we cannot fully understand the organism unless we grasp why each step in its development was necessary if maturity was to be reached; and this in turn requires a grasp of the forces and processes involved and of the agencies which give rise to them. Just as, in brief, composition and organization are correlative aspects of the natural unit which cannot be described separately, so the forces which produce a thing and the thing itself as end product cannot be described separately.
In short, since all explanation assigns reasons why, i. e., states causes, any given explanation must be either factorial, in which case it states all four relations which respond to the question why; or reductive, in which case a mathematical expression is taken for the only or fullest rational understanding possible, or else it is a question of a methodology which is not transparent to itself, which misunderstands its own dimensions and their interrelations. This latter type of reductionism is characteristic indifferently of atomistic and mechanistic explanations.
Historically, until very recent times, mathematicism and mechanism have always been closely associated, no doubt because mechanism provides a way of giving to a mathematical theory a physical, imaginable model; but conceptually the two approaches to explaining natural change are quite distinct.
Historically, these three distinctive explanatory modes were first articulated and consciously employed by the early Greeks, and despite their subsequent sophistication in application to ever extended areas of experience, they still and will always express the distinctive point of view and method associated, respectively, with Aristotle, Plato, and Democritus.
For our context, these remarks are helpful in that they provide a background against which it becomes possible to see that in order to resolve the " family quarrel" between the Linnaean theory of a fixed and immediate creation of species and the Darwinian theory of the evolution of species, biology had to resort to the methods of reductive analysis, what we may call empiriological (changing our terminology here, be it noted, from that of previous authors) as against typological thought, understanding by this latter term all those theories of specific natures which are characterized by a tendency to identify natural kinds with essential kind in the metaphysical sense and so to perpetuate the myth consequent on the error of univocally ontologized kind-essences (or even to supplement or supplant it with the myth of vitalism as well).
Such a resort to empiriological rather than philosophical formulations was possible because, even though, as Waddington has shown, the real objects of interest to evolutionary science are subjects of processes which require a factorial rather than a reductive analysis, nonetheless, involved in organisms as undergoing constant change are certain invariant relationships as expressed in the Hardy-Weinberg equation that underlies modern population genetics. Such a resort was probable in the cultural context of modern science which tends to regard physico-mathematics as the paradigm rather than one mode of rational understanding. Such a resort was perhaps necessary in the face of the refusal of typologists generally to respect integrally the requirements of parsimony.
In any event, it is a fact that the mathematical formulae of population genetics, as theoretically elaborated in the brilliant works principally of Fisher, Wright, and Haldane,221 structure operationally the professional scientists' understanding of evolution. With a certain justice Ernst Mayr holds the opinion that " history shows that the typologist cannot and does not have any appreciation of natural selection," because " the typologist interprets natural selection as an all or none phenomenon." " Basically," therefore, " the arguments of the antiselectionists rest on an inability to appreciate the statistical nature of selection."222 Since, moreover, typological thinking once characterized the thought of the West, and its scientific thought as much as and in some ways more than its philosophical thought, Dobzhansky considers that it was impossible to express in a convincing way the complexity, power, and subtlety of evolutionary selection's operation over the two billion years plus of life's history on this planet until the discussion could be placed on a quantitative basis.223
In terms of this " quantitative basis," Dobzhansky summarized the present empiriological state of the question in a set of passages which we may cite directly for reasons of both economy and clarity.
Platonic philosophy [which is Dobzhansky's term for what Mayr calls more accurately typological thinking] considers the elusively multiform, always changing natural phenomena to be mere shadows of the immutable ideas, of the eternally fixed essences of things. This philosophy has appealed to many scientists. Individual organisms and living populations are often supposed to represent imperfect incarnations of ideas, patterns, or types of their respective races, species, genera, etc. In 1896, the great anthropologist Virchow defined human races as " acquired deviations from the original type." Acceptance of the biological evolution theory did not completely overcome the notion that the annoying variability
221 Their classics are: R. A. Fisher, The Genetical Theory of Natural Selection (Oxford: Clarendon, 1930); S. Wright, " Statistical Theory of Evolution," Genetics, 16 (1931), pp. 97-159; J. B. S. Haldane, The Causes of Evolution (New York: Harper, 1932).
222 Mayr, Animal Species and Evolution, pp. 183, 184, and 185, respectively.
223 Dobzhansky, Mankind Evolving, p. 140.
page 295
of individuals is somehow a false front which conceals slowly changing racial or species types. The fiction of types is indeed helpful for the purpose of classification and of cataloguing organisms.224
([Thus:] A museum systematist is perforce confined to describing the structural differences in his materials. The assumption implicit in his work is that a fraction of genetic differences between populations are reflected in morphological traits, and, hence, the morphological descriptions reflect reasonably accurately the magnitude of the genetic differences between the races, species, genera, etc. This assumption is on the whole justified, but some groups are known in which the genetic divergence may be accompanied by little morphological divergence.225 [Similarly:] It is also a great, though highly misleading, simplification for a physiologist or a medical man to believe that different individuals, or different patients, should react alike to similar treatments.226 [Yet:] Although any change in the bodily structures is of necessity a sequel to physiological developmental processes, some physiological differences are not accompanied by detectable changes in the visible morphology.227)
The fictitiousness of the types has been shown by the Hardy-Weinberg's demonstration of the genetic equilibrium. The spatio-temporal entities in sexually reproducing and cross-fertilizing organisms are individuals and Mendelian populations. Every individual carries a constellation of genes, which is not likely to be found in other individuals. A population has a gene pool, from which the genes of individuals spring and to which they usually return. Gene frequencies and variances, rather than averages, characterize Mendelian populations. Superficially considered, natural populations of most species seem to consist of normal, or wild-type, individuals, which owe their origin to mutation. A closer study shows that the wild-type is also a fiction. " Normal " individuals are actually a heterogeneous collection of genotypes, the common property of which is that they possess a tolerable adaptedness to the prevailing environments. When the heterogeneity happens to be striking to the eye, or easily detectable by some method, it is referred to as polymorphism. Polymorphism is a loose descriptive term; all Mendelian populations are more or less polymorphic.228 ([Thus, for example:] Sibling species are reproductively isolated
224 Dobzhansky, Genetics and the Origin of Species, p. 108, my emphasis.
225 Ibid., p. 267.
226 Ibid., p. 108.
227 Ibid., p. 267.
228 Ibid., 108-9, my emphasis.page 296
Mendelian populations, the members of which show few or no easily visible differences in the bodily structures.229 Some authors have argued that sibling species should not be considered species because museum taxonomists can not distinguish them in materials preserved by time honored methods. Species are, however, phenomena of nature which exist regardless of our ability to distinguish them.230)
For over half a century evolutionists held for the concept of natural selection against the persistent denials and arguments of the typologists; but not until the discovery of Mendelian heredity could they deal with the concept in an adequately operational manner, in a manner, that is, which could effect a demonstratio ad oculos (for those with eyes to see) . The reason is simple. " The essence of Mendelian heredity is that it is particulate "; and it is precisely " the particulate nature of inheritance [that] enables calculations to be made as to the proportion of offspring of different types in different generations after a cross. Like the atomic theory in physics, it is the basis of quantitative treatment." 231
Thus, for example: " ' Improbable ' events and constellations of genes play a role in selection difficult for the typologist," viewing the fossil record, " to understand." 232 Yet, as Mayr (among many others) simply comments:
229 Ibid., p. 267.
230 Ibid., p. 269.
231 Huxley, Evolution: The Modern Synthesis, p. 47. In his " New
Introduction "
to this classic study for the 1964 Wiley & Sons edition, Huxley notes: "
The most
comprehensive and up-to date exposition of the synthetic theory of
evolution has
just been given by Ernst Mayr in his magistral book, Animal Species
and
Evolution (1963) . As he points out, a radical change in recent evolutionary
thinking has been ' the replacement of typologic thinking by population thinking.'
However, the modern synthetic theory still retains the combination of
induction and
deduction that underlay Darwin's original theory (p. iii) ."
232 Mayr, Animal Species and Evolution, p. 187. It is obvious and has to my knowledge never been denied that while genetic mutations are " random " with respect to the adaptive needs of the organisms in which they occur, they are not at all " random " with respect to the internal structure and chemical constitution of the gene which mutates and the factors at play thereon -- including the influence of the immediately surrounding genes (of the " genotypic milieu ") . " Mutations are limited," Spuhler points out, " by the structure of the gene which mutates and this structure is determined by the . . . forces . . . active in the history of the gene." (" Somatic Paths to Culture," in The Evolution of Man's Capacity for Culture, ed. by J. N. Spuhler, Detroit: Wayne State University Press, 1965, p. 4).
Nonetheless, from within a reductionist perspective, or rather, in trying to get beyond reductionism without abandoning the accordance of primacy to a reductionist type of explanation, it is natural to have to resort to the most elaborate of theoretical contrivances in order to maintain some measure of contact with the sound intuitions of common sense. Thus Chomsky (in Language and Mind, New York: Holt, Rinehart & Winston, 1968, p. 83 and fn. 26 p. 88) seems to regard as some sort of fundamental breakthrough or basic insight the fact (" the non-trivial fact," as the phrase goes) that " it has been argued on statistical grounds-- through comparison of the known rate of mutation with the astronomical number of imaginable modifications of chromosomes and their parts--that such laws '--i. e., " laws that determine possible successful mutation and the nature of complex organisms "--" must exist and must vastly restrict the realizable possibilities. See the papers by Eden, Schützenberger, and Gavadan in Mathematical Challenges to the Neo-Darwinian Interpretation of Evolution, Wistar Symposium Monograph No. 5, June, 1967."
It is true that the Neo-Darwinian perspective is usually conceived in a somewhat reductive manner; but that version of it which regards the rate and direction of mutational change as entirely extrinsic to the nature of the gene which mutates carries the tendency to reductionism to a ridiculous extreme, and one may wonder if one is not confronted here with one of those famous straw men which fill the writings of philosophers concerned with refuting other positions. " Typically," notes Schwartz (art. cit., p. 360), " mathematics knows better what to do than why. Probability theory is a famous example." One is hardly justified in asserting on such a basis that to attribute the development of organisms across prehistory to evolutionary selection " is perfectly safe ... so long as we realize that there is no substance to this assertion, that it amounts to nothing more than a belief that there is some naturalistic explanation for these phenomena." (Chomsky, p. 83). That nature always underlies the random is an insight quite independent of statistical arguments, which is at least as old as Aristotle (see Physica, II, chs. 2-6, esp. 198a9, inter alia); and to assert that the laws determining this underlying structure and function remain shrouded in " total mystery " (Chomsky, p. 83) is to dismiss at a stroke not just the research into DNA, but the whole of evolutionary biology as though it did not exist, or consisted entirely of groundless conjecture.
Mathematicians have pointed out that evolution deals with numbers of such astronomical dimensions that even ' improbable' events may occur. Most species have millions of genetically unique individuals in every generation, each producing thousands or millions of gametes. There are thousands or millions of generations during the geological life span of each species. Under these conditions an event may become a certainty even if the chance of its occurrence is only one in a billion. Yet the total number of possible genotypes in a species is infinitely greater than the actual number of individuals.232a
232a Mayr, Animal Species and Evolution, p. 187. See also Dobzhansky, Genetics and the Origin of Species, pp. 254 and 255: " Nothing can be more certain than that only an infinitesimal fraction of the possible gene combinations can ever be realized in organisms the genotypes of which consist of hundreds of thousands of genes. The potentially possible gene combinations constitute, however, the ' field' within which evolutionary changes may occur. The adaptive values of the gene combination are, of course, not alike." ". . . gene patterns which differ in only a few genes usually have more or less similar adaptive values. The patterns with superior adaptive values form the ' adaptive peaks'; the peaks are separated by the ' adaptive valleys' which symbolize the gene combinations that are unfit for survival and perpetuation." (It is noteworthy that, at any given stage in the geologic environmental sequence, " some gene combinations which actually appear from time to time, and probably the vast majority of the potentially possible ones, are discordant and unfit for survival." [Ibid., p. 254].)
Thus we find in contemporary biology, even as at various other stages in Western intellectual history, a working explanatory combination of a mechanistic model with a mathematical theory. We have already noted how the method of converting a physical description into a mathematical one can either be mistaken for the constitution of a new level of natural science, and so become a reductionism, or be rightly recognized as an instrument used by the natural scientist--a technique, albeit exceptional, like his other techniques--in his effort to analyse and discriminate the factors of processes, their always fourfold reasons for being.
We have also seen, in Section IV above, how the establishment in evolutionary science of the factorial as superordinate to the reductive view of causation, already implicit in Darwin's work, has only recently and not yet universally come to be recognized as inevitable for the further maturation of the evolutionary explanatory scheme.
Now we are in a position to see how this tendency to reductionism in evolutionary theory has generated a false issue in philosophy by requiring a choice between an evolutionary process which was tending toward man as to an end, and therefore had to be a predetermined unfolding leading steadily to man along a central line of advance visible in the fossil record, or an evolutionary process in which randomness and opportunism play a central role, and which therefore could neither be predetermined to advance along a central line nor oriented to man as toward an end in some sense.233
233 It seems to me that this is reflected in T. A. Goudge's well-known study, The Ascent of Life (Toronto: University of Toronto Press, 1961).
To achieve this perspective, it will be necessary and sufficient to show that a random, opportunistic process the actual course of which could not be foreseen in advance is not incompatible with an evolution necessarily tending toward man. In other words, the reductionist tendency in biology has generated a false issue by making it impossible to recognize that there need not be a pre-determined end-point in order for an over-all system of processes to change deterministically along a definable and recognizable course as time passes by reason at once of the closed, circular causal organization of the system, and of the irreducible levels or zones through which the system must pass if the causes of its sub-processes remain operative.
We will proceed in two steps. First, we shall show, with Waddington's help, why the reductionist or empiriological formulation of the evolutionary mechanism must reject the thesis " that it is possible to discern in the results of evolution some general overall direction of change which can truly be regarded as a special direction," inasmuch as " the direction is one which in some way arises as a result of the general structure of the universe; that is, it is not merely a direction in which progress happens to have occurred, but, in some of its aspects at least, it has the character of an inevitable consequence of the nature of the evolutionary process and the organisms involved in it." 234 In short, we shall see why a reductionist view is incapable of making sense out of the datum of progress as such in biological evolution.
Second, we shall show that even by adopting the perspective consequent on a mechanistic view of evolutionary causation, the arrangement of the living world in an over-all hierarchical pattern is a necessary result of the operation of evolutionary selection.
Then, in Section VIII, we will see in what sense it is possible to discern interior to this imperfect empirical hierarchy a perfect hierarchy of irreducible intelligible grades. In that way it will be seen how the notion itself of species in traditional
234 C. H. Waddington, " The Possibility of Evolutionary Theory," in The Ethical Animal, p. 65.
philosophy--once shorn of its ambiguities and uncertainties-- can render the evolutionary data concerning species more intelligible in their own line of explanation which is not mathematical nor mechanistic (the natural kinds are no more mere proportions of genes than they are numbers) but that of natural philosophy, wherein are assigned proper reasons for the endless changes in nature.
Concerning the first point, then, the following passages are sufficiently clear:
Most biologists at the present day, in expounding evolutionary theory, seem to be content to leave it that the mechanism by which evolution has been brought about is composed of these two major factors: the genetic system with random mutation on the one hand and natural selection on the other. The evolutionary pressures exerted by these two factors are exhibited as being quite external to the nature of the organisms involved. The evolutionary pressure exerted by the genetic system is that of mutation, and mutation, it is explained, is a random process. Any explanation which might be offered for the nature of the mutational changes would have to be found, it is asserted, in the chemical composition of the genes and not in the nature of the complete biological organism in which these genes are carried. Mutation thus appears as essentially an external force to which the organism passively submits. Again, natural selective pressures are usually thought of as arising simply from the external environment. When the climate changes, a new predator appears, or industrial fumes blacken the tree trunk on which the animal lives, the populations of organisms concerned cannot, it is usually implied, do anything but submit to these pressures and wait until the equally uncontrollable process of mutation throws up a new hereditary variant which enables them to meet the environment's challenge more successfully.235
Now, with such a mechanism--random mutation in selective but unresponsive environments--it would appear difficult to find any principle which would produce any specific direction of evolutionary change. All evolution would appear to be purely a contingent phenomenon, which just happened to go in the way that it did, but for no ascertainable reason. One could admit, of course, that the mechanism of natural selection is one which will, as has been
235 C. H. Waddington, " The Biological Evolutionary Theory," in The Ethical Animal, p. 88.
frequently pointed out, produce states of extreme improbability by preserving just those particular chance variations which happen to fit in with the environment and rejecting all others, but there seems at first sight to be nothing which could decide as to which state of improbability will be favoured.236
Within an explanatory perspective basically similar to this, it is evident why Dobzhansky, following Simpson and Blum, can only conceive, " broadly speaking, two kinds of interpretations of evolution. One kind supposes that any and all evolutionary changes that ever occurred were predestined to occur. The other kind recognizes that there may be many different ways of solving the problems of adaptation to the same environment; which one, if any, of these ways is in fact adopted in evolution escapes predetermination."237 In fact, there is a third kind of interpretation. Plato and Democritus between them did not exhaust the possibilities of causal explanation--only the reductive conceptions of it.
But secondly, and what is of much greater significance than the foregoing negative point, evolutionary theory today requires--and this is agreed to by all who understand it--that because the diversity and discontinuity of the living world on the one hand, and its adaptation to the environment on the
236 Ibid., p. 89. I have no doubt that G. G. Simpson would reject this sketch of Waddington's as accurately capturing his understanding of the evolutionary mechanism. " It was a crude concept of natural selection," he writes (The Meaning of Evolution, p. 223), " to think of it as something imposed on the species from the outside. It is not, as in the metaphor often used with reference to Darwinian selection, a sieve through which organisms are sifted, some variations passing (surviving) and some being held back (dying). It is rather a process intricately woven into the whole life of the group, equally present in the life and death of individuals, in the associative relationships of the population, and in their extraspecific adaptations." I have no doubt either that Simpson's grasp of the process indeed is much more subtle than Waddington's Dührer-like etching. But all that is quite beside the point. As long as one insists on stating the four-factor process in two-factor terms, one cannot completely escape a reductionist tendency toward what Waddington describes as toward an ideal limit.
237 Dobzhansky, The Biology of Ultimate Concern (New York: The New American Library, 1967), p. 61. See also H. F. Blum, "Dimensions and Probability of Life," Nature, 206 (1955), p. 131; and G. G. Simpson, "The Nonprevalence of Humanoids," in This View of Life, pp. 253-271.
other, are seen as causally related, the arrangement of the natural kinds must be structurally hierarchical. This has been clearly stated by Julian Huxley:
Improvement of general organization is brought about by a succession of successful types. Each type achieves its evolutionary success by virtue of superior organization, and as a result evolves into a new taxonomic group which radiates (undergoes cladogenesis) at the expense of the earlier groups in competition with it, including the group of similar taxonomic rank from which it has originated, though this may and usually does persist in reduced numbers. This process appears to apply to the anagenesis [upward evolution] of all taxa from the genus upward, and indeed inevitably results in a taxonomic hierarchy.238
Thus, even within the insufficiently differentiated (so far as the modes of causation go) explanatory scheme according to which " natural selection is the only objectively established antichance evolutionary factor," 239 the main modes under which
238 Huxley, Evolution: The Modern Synthesis, " New Introduction " (1964), pp. xxii-xxiii, my emphasis.
239 Simpson, This View of Life, p. 228. " The theory does not demand
and the
facts do not indicate that selection is always effective or that at its most
effective, it can eliminate all unfavourable mutations immediately." (The Meaning
of Evolution, p. 224). What the theory does require, however, the facts do
obligingly indicate--specifically, that " by and large, high Darwinian fitness (i. e..
reproductive success) does go together with the maintenance or advancement of
harmony between the organism and its environment." (Dobzhansky, Mankind
Evolving, p. 130). Thus Dobzhansky observes that, while " we must beware of
thinking that the nature of an organ is explained [exhaustively or even quite
adequately] by finding out the function which this organ performs," among contemporary scientists " the fear of teleology can be carried too far. Some biologists
go to the extreme of saying that the function of an organ has nothing to do with
its being there. Yet nobody can deny that man has eyes to see with, and a
mosquito has its mouth parts to get blood with. It is pedantic to quibble even
about the statement that the purpose of the eyes is seeing. There is really nothing
objectionable about such a statement which simply describes what the organ does,
provided that one always keeps in mind that the presence of an organ and its
function are at the opposite ends of a long and complex chain of cause-and-effect
relationships. Some of the connecting links in this causal chain are the processes
of mutation, sexual recombination, and natural selection over a long series of generations." (Dobzhansky, Evolution, Genetics, and Man, p. 231; emphasis supplied).
It is in the light of the evolutionary process which molds an organ gradually so
that it becomes increasingly apt for the performance of a given adaptive function
that one sees clearly the advantage of replacing the historically overtoned term
selection operates are sufficient to guarantee a hierarchical arrangement of forms, albeit imperfect and susceptible of multilinear
" teleology " with the modern term coined to denote precisely the phenomena of evolutionary adaption, " teleonomy." (The case is analogous to the substitution of " astronomy " for " astrology "). See Ernst Mayr, " Evolution and Causality."
Thus C. S. Pittendrigh remarks (" Adaptation, Natural, Selection, and Behavior," in Behavior and Evolution, pp. 396 and 393-4): " The refusal to admit that the turtle came ashore to lay its eggs was intended as a pious assertion that a causal analysis was the only proper course open to the biologist. But it is clear now that no organization--living or non-living--is ever fully explained by a causal," i. e. (as the author makes clear in context), physiological, " analysis of its operations." " Another way of putting this is to say that an exclusively causal explanation of life is possible but only if organisms are not abstracted from their concrete history." All in all, " today the concept of adaptation is beginning to enjoy an improved respectability for several reasons: It is seen as less than perfect; natural selection is better understood; and the engineering physicist in building end-seeking automata has sanctified the use of teleological jargon. It seems unfortunate that the term ' teleology' should be resurrected and, as I think, abused in this way. The biologist's long-standing confusion would be more fully removed if all end-directed systems were described by some other term, like ' teleonomic,' in order to emphasize that the recognition and description of end-directedness does not carry a commitment to Aristotelian [?] teleology as an efficient causal principle."
And to these remarks we may append the interesting comments of Maritain (" Ontology and Empiriology in the Study of the Living Organism," in The Degrees of Knowledge, pp. 192-4, passim,): " It would certainly be foolish to ignore the role already played by physico-chemical analysis (and hence calculation) in biology, a role which is destined to increase daily. . . . As a matter of fact what is so studied is the material conditioning, the material means of life. And, since everything within the living organism is effected by physico-chemical means, this analysis can and should progress indefinitely." " Does this mean that some day it will exhaust biological reality? By no means. For if within the living thing everything is effected by physico-chemical means, everything is also effected by the soul (and its vegetative powers) as first principle. . . . Thus, for example, while the ontological concept of finality has its place among the explicative concepts of the Philosophy of Nature, the facts of biological finality represent for physico-chemical analysis only an irrational that must be reduced as much as possible. And, for the properly biological experimental analysis of which we have been speaking, those facts come under an empiriological concept that may be designated by the same name of finality, but which should be completely recast, and emptied of its philosophical significance. Here, leaving aside any use of finality as a causal explanation, it will merely express that general pre-explicative condition," i. e., a condition of simple observation presupposed by the explanation and which itself plays no explicative role, " that the junctions of the living thing, and the use it makes of its own structure, serve for the continuance of life. As for the concepts of the soul and of vegetative powers, they play an indispensable role in the Philosophy of Nature, but remain outside the domain of properly biological experimental analysis as well as of the physico-chemical analysis of the phenomena of life." On the metaphysical bases of the empirological formulation of finality, see the same author's A Preface to Metaphysics (New York: Mentor Omega, 1962), " The Principle of Finality: First Aspect," pp. 103 ff.; " The Principle of Finality: Second Aspect," pp. 107 ff. It was in this connection that Bergson was able to remark (though without anything like an accurate understanding of the factors providing his basis): " The philosopher, who begins by laying down as a principle that each detail [of the evolutionary process] is connected with some general plan of the whole, goes from disappointment to disappointment as soon as he comes to examine the facts; and, as he had put everything in the same rank, he finds that, as the result of not allowing for accident, he must regard everything as accidental." (Op. cit., p. 116: emphasis supplied. Cf. Simpson, The Meaning of Evolution, pp. 121 and 167). It is precisely in disclosure of a contingent substantial dimension in the world of necessary natures that the evolutionary concept strikes at the heart of nineteenth-century idealism (see G. W. F. Hegel's statements in Enzyklopädie der philosophischen Wissenschaften, ed. by F. Nicolin and O. Pöggler [Hamburg: F. Meiner, 19591, par. 249, p. 202), and perhaps, at any "Whiteheadian " philosophy of organism " as well. See Ashley, " Change and Process." See also Merleau-Ponty's critique of the reductionist conception of causality in biology, as sketched by Remy Kwant in The Phenomenological Philosophy of Merleau-Ponty (Pittsburgh: Duquesne, 1963), esp. pp. 18-20, "The fundamental character of subjectivity."
arrangements.240 " Indeed it can be argued," observes Nogar, " that in the evolutionary sequence of naturally related species, we find the same hierarchical order on the horizontal (space-time) plane that St. Thomas finds on the vertical plane of existing organisms." 241 It is clear from this that, even if we adopt a reductive perspective within the explanatory scheme of modern evolutionary science, the modern and traditional species problematics do interarticulate; but since "no set of terms which are constituted by diverse positive differences, rooted in diverse perfections, can be hierarchically ordered as essentially higher and lower inter se," 242 it remains to show in what manner the perfect hierarchy of essential species may without contradiction exist within the imperfect hierarchy of genetic and morphological species, and how the former renders the latter more intelligible in its own line.
240 The main modes of selection can be reduced to four: 1) It determines the direction of evolutionary change (dynamic or directional selection); 2) It diversifies living things along the available economic paths open to the forms at any given time or place (diversifying selection); 3) It maintains the level of existing adaptive improvements (normalizing, centripetal, or stabilizing selection, within the group; balancing selection between groups); 4) It " neglects," i. e., the absence or deficiency of adequate centripetal selective pressure allows degeneration.
241 Nogar, " Evolution: Scientific and Philosophical Dimensions," p. 30.
242 Adler, " Solution of the Problem of Species," p. 323.
VIII. The Two Hierarchies
We have seen in all the foregoing that contemporary evolutionary science maintains the reality of substantial species both secundum se and quoad nos, and that this suffices to remove the direct contradiction between the scientific conception of nature and the hylomorphic conception. We have shown moreover that the scientific notion of species implies their hierarchical ordering, in an imperfect or multilinear sense. On the other hand, we have made reference to the fact that the traditional concept of species as essential kinds implies a hierarchical ordering in a perfect or unilinear sense.243
In order, finally, to show how these two views, far from being incompatible, are mutually illuminating, we shall have to establish four further points. First, it will have to be shown how the genetic conception of the individual organism implies a doctrine of substantial form. Second, we shall have to show how the doctrine of substantial form set in the context of the possible modes of difference leads to a doctrine of essentially distinct " species," or, more exactly, of irreducible grades of being through which any process of anagenesis on any planet would have to pass if it were to continue. Third, we shall have to show how, in the existential establishment of these grades, there is room for the unforeseeable and the undetermined-- for chance and the opportunistic--without the phenomenon of progress being reduced to a mere contingent path. In other words, we shall see why the fact that " the fossil record shows very clearly that there is no central line leading steadily, in a goal-directed way, from a protozoan to man," that there has been instead " continual and extremely intricate branching," so that " whatever course we follow through the branches there are repeated changes both in the rate and in the direction of evolution," 244 is entirely compatible with and even implied by
243 I consider the available literature on this point to be demonstrative. See fn. 124 above. If I am mistaken, I shall be glad to be so proven.
244 Simpson, " The Nonprevalence of Humanoids," in This View of Life, p. 265. Simpson develops this point thoroughly in The Meaning of Evolution; see esp. ch. X' " The Problem of Problems," pp. 123-9.
the fact that only the essential thresholds of ontological difference exhibit an a priori necessity and (in that sense) predetermination--a " hypothetical necessity ": if there is a development of life, then there are only three possible levels which it can traverse.245 Finally, we shall have to consider the causal possibility of the passage from " lower " to " higher " grades.
Then the influence of Darwin on philosophy and vice versa --the mutual implications of the modern and traditional " species " problematics--will be clear.
To begin with the first point, we are right back with the question of the difference between science and philosophy in terms of their relation to experience. In the particular case that concerns us now--the transition from genetic to substantial individuality--the medium is the organizational correlate of structure identified by Aristotle as " formal cause." We know that the " material cause " of the individual organism, the compositional correlate of structure, are DNA-RNA molecular groups, genes, chromosomes, etc. We know that what differentiates them is not only their different components but the way these components are arranged with respect to one another--their organization. This is summed up by Mayr and others by reference to " the unity of the genotype," the fact that, although the genes are transmitted as more or less discrete, unblending units, they function as interacting and cooperative sets in the organism's development, controlling the metabolic pattern as such which governs the development of the organism as a whole and establishing a " reaction range " outside of which the organism cannot be pushed without ceasing to be itself. Thus in the concept of the genotype as circumscribing both the capacity and the limitations for development of the organism there is a twofold element, an empirical, sensible element subject to observation and direct manipulation (the arrangement of the genotypic components with respect to one another) and an intelligible, non-empirical element, the unity itself of the genotype, expressible through
245 See De Koninck, art. cit., p. 240.
and demonstrable in the phenotype, which is inferred and without which the " organism as a describable object" would not be possible, but which is directly neither observed nor observable. Now that principle of unity, which is not that which exists but that by which the individual exists as a describable object identical with itself and distinct from all others, that intelligible ground of the prior possibility of a determinate being, is exactly what traditional philosophy intended by its notion of substantial form--" the first act of any material entity which determines its matter and gives it a constant tendency toward further completion."246 (A parallel analysis of the intelligible a priori involved in the empirical composition of the genotype leads in exactly the same way to the traditional notion of primary matter as the capacity common to specifically or recognizably distinct unities to be converted one into the other.)
In my opinion, it may be going too far to say that here the concept of formal causality (parallelly, material causality) divides before the mind, so to speak, according to two specifically different modes of defining, one by resolution into the sensible, the other by resolution into the intelligible--the famous " perinoetic " and " dianoetic " intellections differentiating the " empiriological " realm of science from the " ontological" realm of natural philosophy--for the reason that the observable, manipulable organization and composition themselves require the inference of " form " (materia actuata) and " matter " (materia actuabilis) as intelligible principles of the intrinsic constitution of existing and genetically constituted individuals. Nothing more is involved in these two levels from the philosopher's point of view, it seems to me, than the distinction between first and second act.
However this may be, our point is clear: the genetic conception of individuality is not only not opposed to the hylomorphic conception, but from the standpoint of intelligibility it directly implicates it.
246 Cf. John Wild, Introduction to Realistic Philosophy (New York: Harper, 1948), p. 506.
Our next step is to demonstrate that the hylomorphic composition of natural units, the individuals or " substances " of nature, necessarily implies that if there are individuals which differ by reason of properties in the strictest ontological sense, properties rooted in the intelligible a priori constitution of possibly different beings as consequent on the form alone, these individuals are related by reference to these properties in a unilinear way.247 This will require but an application of the logic of definition to the possible modes of difference.
Let us begin by restating the possible modes of difference.248 Some things differ only in degree: the difference between the two things may be rooted in one and the same perfection possessed by both in different quantities, in which case it will be signified by a positive term with varying quantification that signifies more or less of the same. On the other hand, some things differ in kind: either the difference between the two things may be rooted in two " perfections " or determinations related by contrariety, in which case it will be signified by two positive terms, each signifying the possession of one of the two contrary determinations,--e. g., the difference between placentals as a class and marsupials as a class; or the difference between the two things may be rooted in one of two determinations related cumulatively (i. e., so related that whatever possesses X must also possess Y, but not e converso, where X is the " cumulative " and Y the " accumulated " perfection, and this deficiency with respect to X may be a condition either of privation--simple indetermination--or of negation-- determinate exclusion), that one or ' root' perfection being the cumulative determination or perfection, in which case it will be signified by a positive and a negative term, the former signifying the possession, the latter the rejection, of that one perfection--e. g., a) whatever has wings (cumulative perfection) must have externally specialized organs (accumulated
247 See Adler, The Problem of Species, pp. 110-111 and fn. 141, p. 111.
248 Here I am basing myself on and to a certain extent presupposing Adler's analysis in " The Hierarchy of Essences." Anyone who wishes proof that all the really possible modes of difference are being considered should consult this article.
perfection), but not everything with externally specialized organs need have wings, though it will necessarily have some positive alternative, paws, for example (coordinate perfections cumulative of the same determination); b) whatever has hoofs (cumulative perfection) must have externally specialized organs (accumulated perfection), but the ungulates or hoofed animals may differ among themselves as odd-toed--perissodactyls, or even-toed--artiodactyls (two contrary perfections cumulative of the same determination); c) whatever is capable of self-replication (cumulative perfection) must be a material substance (accumulated perfection), but not every material substance is capable of replication (supraordinate relation of cumulation).
If we translate this analysis into the terms apparent, superficial, and radical difference in kind which we have used throughout our preceding phases of analysis, we get the following correspondence.
An apparent difference in kind is plainly a subordinate mode of difference in degree: when, between two things being compared, the difference in degree in a certain respect is large, and when, in addition, in that same respect, the intermediate degrees which are always possible are in fact absent or missing (i. e., not realized by actual specimens), then the large gap in the series of degrees may confer upon the two things being compared the appearance of a difference in kind; really they differ in degree.
Translating the superficial and radical difference in kind is a bit more tricky. On the one hand, an observable or manifest difference in kind may be based on and explained by an underlying difference in degree, in which one degree is above and the other below a critical threshold in a continuum of degrees; such differences in kind are real, and are termed " superficial " only to indicate that what underlies and explains them is a difference in degree involving a critical threshold, so that a given degree is either above or below the threshold (e. g., ice/water/steam) correlated with either the presence or absence of the property in question with respect to which no intermediates
are possible. On the other hand, an observable or manifest difference in kind may be based on and explained by the fact that of the two things being compared one has a factor or element in its constitution that is totally absent from the constitution of the other, in consequence of which the two things, with respect to their fundamental constitution or makeup, can also be said to differ in kind; such differences in kind, no more real than the preceding ones, are termed "radical" only to indicate that the observable or manifest difference in kind is itself rooted in an underlying difference in kind.
Now it is clear that, by the above definitions, two things may differ superficially in kind when their difference is rooted in contrariety and when their difference derives from cumulatively related perfections; all the examples given above to illustrate the contrary and cumulative modes of difference in kind could from a genetic standpoint be construed as superficial differences in kind. Nonetheless, among the examples of cumulative modes of difference, there is an important difference from the standpoint of logic which shall have to be looked at more closely, which is that, in all the examples given except in that involving replication as a root power, the differentiation of the two kinds involved three distinguishable perfections of which each species or kind possessed two. In the example involving reproductive capacity, the differentiation of the two kinds involved two, not three, distinct perfections of which one kind possessed both and the other only one.
Now, let us call all differences in kind which involve three determinations, or two contrary determinations, " differences according to mode Alpha "; and those which involve only two determinations or perfections cumulatively related, " differences according to mode Beta." In terms of the logic of definition,249
249 Adler, " The Hierarchy of Essences," p. 16: " A kind is a definable species of thing. The definition of a species or kind, whether it be accidental or essential, involves stating a genus and a difference. In order not to beg the question about the essential as opposed to the accidental, let us use these three terms--' genus,' ' difference,' and ' species '--in the following manner. Let ' genus ' signify whatever is common to two kinds differentiated: i. e., let it signify one or more perfections which the things being differentiated possess in common. Let ' difference' signify a perfection (or a set of inseparable perfections) possessed by one kind and rejected by the other. Let ' species' signify a kind as constituted by one or more perfections which it has in common with another kind, combined with the perfection, possessed or rejected, by which it is differentiated from that other. Hence whether the kind under consideration is essential or accidental, defining the species requires us to state its genus and its difference.
" So far we have used all these terms--' genus,' ' difference,' ' species,' and ' definition '--with systematic ambiguity, so that they are equally applicable to all kinds, whether they are differentiated according to mode Alpha or mode Beta. Now let us remove that ambiguity by seeing the altered signification of these terms as we pass from one mode to the other." (See the further discussion in fn. 250a below.)
it is easy to see that all those kinds defined according to mode Beta will always and necessarily be related to one another unilinearly as subordinate and supraordinate, never as coordinate, contrary, or multilinear. " That differentiation according to mode Beta makes one species supraordinate to the other follows from the fact that one possesses the perfection or perfections possessed by the other and in addition possesses a perfection lacked by that other. This fact not only causes one species to be higher than the other, but also is the key to the hierarchical ordering of all species thus differentiated." 250
We have here an antinomy.
Since Alpha and Beta exhaust the modes according to which things can differ in kind, since moreover from a genetic point of view (equivalenty: from an exclusive standpoint of material cause) things which differ according to either mode fit the definition of superficial difference in kind, whereas from a logical point of view only mode Alpha fits the definition of a superficial difference while mode Beta fits the definition of a radical difference, we are forced to ask ourselves whether the only differences in kind ontologically possible are not either apparent or superficial (" differences according to mode
260 Adler, "The Hierarchy of Essences," p. 18. The reader should beware of making any simple parallels between Adler's analysis in " The Hierarchy of Essences " of differential modes Alpha and Beta and my own analysis here; for, as the reader familiar with all three texts will have noticed, in order to correlate the analysis of the modes of difference in The Difference of Man with that in " The Hierarchy" for the present context, it has been necessary to define differential modes Alpha and Beta slightly differently than Adler did.
Alpha"), while the radical difference in kind represents a mere logical construct without application to the realities of the natural world.250a
250a Actually, to speak with absolute exactitude and strictness, since the "superficial difference in kind is one that can be explained by an underlying difference in degree," even though this fact " does not reduce that difference in kind to a difference in degree" (The Difference of Man, p. 25), it would be possible for a geneticist or molecular biologist misconceiving the type of formal autonomy that is proper and possible within his discipline (see M. J. Adler, The Conditions of Philosophy, New York: Atheneum, 1964, pp. 38-9 and 81-9; cf. also David Sidney, Theoretical Anthropology, New York: Columbia, 1953, pp. 39-53, 106-113, and 115-6, inter alia) and in view of the fact that a " critical threshold " as such is neither a genetic constituent, a gene, nor a combination of these, but something consequent on such factors, to argue that even superficial differences represent mere mental constructs and that in consequence there are only apparent differences in the natural world, but no real ones of any genre. Such a view would run counter not only to common experience and the known facts of speciation (see Part I, Sec. V above, esp. pp. 144-6), but it would entail the denial of the possibility of logical discourse grounded in the realities of nature, inasmuch as the law of the excluded middle would be reduced (insofar as it denotes something beyond the simple ontological identity of a thing with itself covered by the principle of identity and valid in a world devoid of non-apparent differences in kind) to the status of an ens rationis cum fundamento in re; and it would become in the end impossible to distinguish between differences introduced into our thought by being and differences introduced into being by our thought--exactly Quintan's dilemma. " The impossibility of intermediates [without reference to serial order] constitutes the discontinuity or discreteness of kinds; only things that differ in kind differ discretely or discontinuously. Another way of saying this is to say that the law of the excluded middle holds for things that differ in kind and only for things that differ in kind. Thus, for example, a whole number is either odd or even. There is no third possibility or tertium quid." (The Difference of Man, p. 20). " When . . . using the word ' continuum ". . . to signify continuous variation--" whether actual or possible, i. e.: " the mode of difference to which the law of the excluded middle does not apply--as contrasted with discrete differences, to which it does apply," one is in the order of physical rather than mathematical discourse. (Ibid., p. 21). " Just as the word ' only' is indicative of difference in kind ... so the words ' more ' and ' less ' are indicative of difference in degree." (Ibid.), (See Aristotle, Metaphysica, X, 7, 1057a21). " When two things differ in kind, no intermediate is possible; the law of the excluded middle applies; and the two things can be said to differ discretely or discontinuously. Thus, for example, an animal either is able to fly or not; there is no intermediate between flying and not flying. When two things differ in degree, intermediates are always possible; the law of the excluded middle does not apply; and the two things can be said to differ continuously. Thus, for example, between any two species of reptile differing in length a third species, having an intermediate length, is always possible. The fact that no fossil or extant species may have this intermediate length does not remove the possibility of there being one." (Ibid., p. 22. Further exemplification with respect to the law of the excluded middle is given on p. 22--vertebrate/invertebrate, viviparous/oviparous, etc.).
Thus the very fact that irreducible differences occur at any level of biological reality--in phenotypical adaptations, for example--and that they can be and are known to be such independently of our researches into them, is already sufficient evidence that it is untenable to contend that the world of nature consists of things which differ only in degree and in no other way beyond numerical existential diversity. See pp. 145-6 in Part I of this article.
page 313
The answer to this question must be found in the tendency of the notion of formal cause to be reduced to an empirical arrangement, whereas beyond this it implies an intelligible principle of substantial unity. If this is well understood, it will be seen that any definition of the individual organism in terms of its genetic structure is not and cannot be an essential definition of what kind of organism it is simply, for the genetic structure is a " compound " inasmuch as it is in the Aristotelian sense at the level of materia secunda, i. e., materia jam actuata --otherwise, it would not be an empirical and directly manipulable arrangement--" and no compound as such can enter into the definition of a form."251 Thus an organism is not a genotype, although every organism must have a genotype.
The difference between accidental form and substantial form is that whereas the former does not make a thing simply be, but only makes it be such or so much--as large or white or anything else of this kind--the substantial form gives it being simply. Hence the accidental form presupposes an already existing subject; but the substantial form presupposes only potentiality to existence, i. e., primary matter.
From this it is clear why it is impossible for one thing to have several substantial forms; because the first makes the thing an actual unity, and if others are added, inasmuch as they presuppose the subject already existing in act, they confer only secondary modifications.252
Three things follow from this. First of all, we may note that not only does an account of the individual organism in terms of genetic organization imply a substantial principle of
251 St. Thomas, In II de anima, lect. 1, n. 222.
252 Ibid., n. 224.
unity but to the extent it ignores that implication it inevitably slips into a mechanistic reductionism; for from an ontological perspective both the composition of a body and its empirical organization qua empirical (as counterdistinguished from what is proper to it as organization over against composition, namely, to bespeak unity of determination over against manifold determinability) are in the order of accidental material disposition, since " the matter of a living body," i. e., a living compound, " stands to the body's life as potency to its act, while this act according to which the body has life is precisely the soul." 253 In the second place, we can now see why real differences in kind could appear from a genetic standpoint as superficial, even if they were in fact radical.254 For this it would be sufficient
253 Ibid., n. 222.
254 From this may be inferred also the reason behind the differing terminology employed in analyzing the modes of difference in " The Hierarchy of Essences ' and in The Difference of Man. Since all the infra-human forms are material actualities simpliciter dicta, it is altogether impossible to demonstrate the radical difference in kind between plant and simple corporeal substance, plant and animal, except in terms of the hylomorphic conception of nature. Because this doctrine unfolds at the level of the intelligible intuition of the unity of the sensibly organized, there is probably no way to formulate an indirect argument for its truth susceptible of strictly empirical resolution (see The Difference of Man, pp. 227-252, esp. p. 232).
On the other hand, because the human form is a material actuality only secundum quid, it should be possible to structure an indirect argument leading to an empirical situation inexplicable on the suppositions of a metaphysical (as distinguished from a methodological) behaviorism (see The Difference of Man, pp. 148-152), i. e., a situation which even from the genetic point view could no longer be defended as a superficially differential situation, and independent of the hylomorphic philosophical theory of nature. (E. g., this was exactly the thrust and exactly the standpoint of my article on " The Emergence of Man: An inquiry into the Operation of Natural Selection in the Making of Man," The New Scholasticism, XL [April, 1966], pp. 141-176; and why I could say that with man, " for perhaps the only time in the history of biological development, a specific discontinuity arose and could only have arisen between two individuals " [p. 170]; whereas from a strictly hylomorphic standpoint such a statement would have been inadmissible.)
The terminology of The Difference of Man was fashioned with this unique structure of human esse in view; whereas, to begin with the terminology of " The Hierarchy of Essences " and then precise it with respect to man's secundum quid materiality would have made the analytical apparatus of The Difference of Man impossibly cumbersome
to ignore or simply never see the intelligible implications of composition and organization in terms of determinability and determination.
For matter certainly is that which as such is not a particular existent, but simply in potency to becoming such. Form, on the other hand, is that by reason of which a particular thing actually exists. While the composite is the particular existent itself; for that is said to be a particular existent (i. e., something you can point to) which is complete in being and kind. And among material things only the composite substance is such.255
From such a standpoint, empiriological in the reductive sense to the end, all that would or could appear would be varying genetic distributions yielding varying phenotypes, sometimes with novel traits, it is true, but traits always reducible to the underlying genetic organization of potentially infinite variation. This is inescapable from within an explanatory scheme which consistently subordinates intelligible implications to the sensible or empiric order, i. e., which never allows the intelligible implications of experience to work themselves out. " When one asks the empiricist what makes the thinking being different from the animal without reason, he can find nothing in the sensible order other than a different degree of organization. From the same point of view St. Thomas would have to reach the same conclusion. Since the empirical conditions are different in the two cases, the resultant phenomena differ: that is all the empiricist finds." 256 For " no composite as such can enter into the definition of a form." 257
In the third place, we can see that things which differ according to mode Alpha are always kinds definable in terms of characteristics or traits which are rooted in the composite, whereas the things which differ according to mode Beta are always kinds definable in terms of a property which follows necessarily from the substantial form as consequent on it alone and due neither to the signate matter nor to the objective
255 St. Thomas, In II de anima, lect. 1, n. 215.
256 A.-D. Sertillanges, L'Idée de création et ses retentissements en philosophie (Paris: Aubier, 1945), p. 147. See however the qualifications in fn. 254 supra.
257 St. Thomas, In II de anima, n. 222.
page 316
circumstances of the thing's existence or operation.258 In traditional terms, all definitions worked out on the pattern of mode Alpha may very well be real descriptive definitions which capture a distinctive life-style and syndrome of characters proper to a stable and unique population within the natural world, but from the side of the metaphysical composition of essence as an a priori established within a determinate grade of being by reason of a formal property convertible with its formal or " specific " difference, such definitions are not and could never become essential.259 The former definitions are definitions of " accidental " unities in the sense that historical causality alone could determine the actual structure and function, for instance, of Pterodactyls; the latter definitions are of " essential " unities inasmuch as whatever the determinate structure of Pterodactyl populations, each of their constituents had to exercise an existence intrinsically determined to an irreducible substantial level or grade of being.
Thus everything which differs according to mode Beta will fit the definition of a radical difference in kind. And there will be as many such differences as there are substantial forms specifically different in the metaphysical sense.
We now see both why a radical difference in kind is indistinguishable from a superficial one from the standpoint of sensible verification, and how these two modes differ in reference to the hylomorphic composition of natural bodies; whereas the latter may or may not be implicated in the eduction of a new substance, the former always is. And as many true properties as there are in the ontological sense, radicated in the form alone (which never exists as such, of course), so many irreducible ontological species will there be in the traditional sense of the term. No one has ever been able to show that there are more than four such grades, and there is every reason to believe that only four definitions are possible which meet the requirements of mode Beta.260
258 See The Problem of Species, p. 190 (cited in fn. 157 supra).
259 See fn. 157 above, and The Problem of Species, pp. 179 ff.
260 See Adler, " Solution of the Problem of Species " and " The Hierarchy of Essences."
From this point of view, the radical kinds alone are species, while all the other articulations of nature, " the class of the birds and the class of the fishes," are sub-species.
While in terms of an analysis of species as natural kinds distinguished among themselves according to the operation of proper causal networks, from the point of view of historical causality, the radical kinds are not species at all, but a priori levels or grades rooted in the intelligible necessities of being, which levels, moreover, can never exist as such but only as realized in genetic populations of substantial individuals.
For purposes of illustrating this idea, let us suppose a finite intelligence contemplating the universe at the period when there was no actually living thing. This intelligence would have been able to foresee with infallibility the emergence of man in this world, and also all those factors which condition absolutely the determination of matter in the line of the human composite: it would have foreseen the plant and the brute, but would have found it impossible to envision all the concrete modes according to which these natural species would be realized. These species, which are quasi-genera in relation to the sub-species, are fixed a-priori, because there is no intermediate point between " to be," " to live," " to know," and " to understand." . . . The inorganic, the plant and the animal are boundary-species and certain. But it is impossible for the determination proper to the sub-species which realize these natural species in a historical fashion to participate in this positive certainty. Otherwise, the modes according to which the animal or the plant would be realisable would be actually determined in matter ahead of time . . . that is to say that there would not only be an idea of matter, but settled ideas.
The intelligence which we have imagined would know with certitude that matter would receive a human form, but it would not be able to say much about the intermediate forms. The throng of sub-species possible is undefinable--between the highest forms of vegetative life and the lowest forms of animal life there is yet again an indefinable number of possibles--and consequently it belongs to the order of the unenvisionable. If one wishes to advance, one must straddle the intermediate forms, each step establishing a clear discontinuity without actual intermediates. Doubtless the structure of the ladder will be determined in a certain measure by the substances given at the outset. . . . But the number and the interval of the stages could not be given in advance. . . . The
surprises which matter reserves for us are undefined. One would have no way of discerning in the initial composite (or composites) a rigid plan of the hierarchy to be established, as if the universe were a multiplication table or matter a subject which received forms coming from without, as the Platonists imagined.
There is therefore a dimension of the unforeseeable in the order of natural determinations: All the sub-species belong at any moment in the existence of the world to the order of future contingents. The hierarchy of these species belongs to history. One understands then why the sub-species " cow " inasmuch as it is cow is philosophically indefinable. It has a determinate truth only a-posteriori, like the actual divisions of a continuum.261
All the essential concerns and decisive interimplications of the traditional and modern species problematics are faultlessly limned in these lines by De Koninck. Such is the true picture of the authentic influence of Darwin on philosophy. For " if the existential establishment of the hierarchy of essences is an opus naturae," the irregularity of the evolutionary progression of the natural kinds such as science exhibits it is perfectly explained.262
This brings us face to face with one further consideration, however, which it is impossible not to come to terms with: the passage from the lower to the higher grades of being, the root problem of evolutionary progress.
Actually, this question is not so difficult as is often supposed. In the first place, in terms of the hylomorphic composition of bodies, it is impossible to deny that it is " the degree of complexity in the scale of organization of organic structures and functions"263 which is the true measure of ontological perfection and consequently the criterion of progress. It is a question of principle, and quite independent of the impossibility of deciding in the particular case whether a butterfly is " more complex " than a moth, an elephant than a mammoth, or an oyster than a clam:
The number and diversity of activities complete in themselves varies in direct proportion to the perfection of the soul in living
261 De Koninck, art. cit., pp. 234-5.
262 Ibid., p. 240.
263 Cf. The Problem of Species, p. 261.
things. The higher the soul the wider is the range of its activities; and the wider its active range the more, and the more distinctly diversified, organs or bodily instruments are required by it. So the relatively greater nobility of the rational soul calls for a greater diversity of its bodily organs, whilst the far lower soul of a segmented animal or a plant has only a narrow field of activity and therefore needs a body that is more uniform and less articulated, and in any part of which, taken separately, it can maintain its being.264
" In short, not every difference in degree of perfection makes a difference in species, but only such as involve grades of being." 265
In the second place, from within the explanatory framework of evolutionary science, and as Darwin himself clearly recognized, adaptation to the contingent circumstances of a changing environment results inevitably in the preservation and development of natural kinds which tend in the long run to mutate in the direction of superior " accidental " (i. e., historical) embodiments of the irreducible grades of being, as a simple concomitant of the fact that adaptive versatility absolutely depends on a versatile (i. e., complex) physical organization:
As species have generally diverged in character during their long course of descent and modification, we can understand why it is that the more ancient forms, or early progenitors of each group, so often occupy a position in some degree intermediate between existing groups. Recent forms are generally looked upon as being, on the whole, higher in the scale of organization than ancient forms; and they must be higher, insofar as the later and more improved forms have conquered the older and less improved forms in the
264 St. Thomas, In I de anima, lect. 14, n. 208. The point is made equally clearly from an " empiriological" point of view (for the sense of this, see the discussion of reductionism in Section VII above) by Julian Huxley in Essays of a Humanist (Baltimore: Penguin, 1964), ch. 2, " Higher and Lower," pp. 39-56. See also A.-D. Sertillanges, " La hiérarchie des êtres," in Le Christianisme et les philosophies (2nd ed.; Paris: Aubier, 1941), pp. 285-288. See also Gredt, n. 519, p. 441 Nota. Moreover, I may add that the cited text from St. Thomas sufficiently indicates the manner in which Pere Teilhard's celebrated " law of complexity/ consciousness" is ontologically founded.
265 AdIer, The Problem of Species, p. 227 fn. 208. Cf. A. G. Van Melsen, Evolution and Philosophy (Pittsburgh: Duquesne, 1965), esp. pp. 97-157.
struggle for life; they have also generally had their organs more specialized for different functions. This fact is perfectly compatible with numerous beings still retaining simple and but little improved structures, fitted for simple conditions of life; it is likewise compatible with some forms having retrograded in organization, by having become at each stage of descent better fitted for new and degraded habits of life.266
In the third place, it is not necessary to deny that " dogs give birth to puppies and not human infants,"267 nor to question the necessity of a proportion between an effect and its adequate cause, nor to adopt a view " according to which all animals (and plants) are but the transitory manifestations of one world-wide life-substance," 268 nor even to invoke " the intervention of causes other than the material energies at work in the starting point and in the environment," 269 in order to account rationally for the transition from the inorganic to the living to the animal. It is necessary and sufficient, in my opinion, to attend simply to one fact and one principle which in truth hold the key to most of the problems generated in philosophy by the evolution of life, whether they center on
266 Charles Darwin, The Origin of Species (edition cited in fn. 13 supra), p. 364. See also J. Huxley, " Higher and Lower," in Essays of a Humanist.
267 "'The implications of evolution contradict our daily experience. When a fish comes out on dry land it dies. Evolution as commonly taught also involves a contradiction of the principle of causality. In our experience every cause is greater than its effect. Dogs give birth to puppies and not human infants. In evolution as so commonly taught every effect is greater than its cause, referring to the development of the major species. By a gradual process of perfection it culminates in the most perfect being of all, man. The world as we know it does not support this view." Carlo, Philosophy, Science, and Knowledge, p. 121. Compare with the view of de Finance, Existence et liberté, pp. 262-3 (cited in fn. 270 infra).
268 A view which Joseph Donceel attributes approvingly to Teilhard de Chardin and Karl Rahner: " Causality and Evolution: A survey of some Neo-scholastic Theories," by Joseph Donceel, The New Scholasticism, XXXIX (July, 1965), p. 296.
269 Donceel's own view, ibid., p. 298. On p. 304 Donceel cites de Finance's position but seems not to have grasped its authentic implications. This is clear from his attempt to introduce via Père Teilhard " a third intermediate notion, that of creative transformation " (p. 306) between the divine creative act and the actions of creatures--a very curious doctrine from one who claims to understand from within, as Fr. Teilhard did not, the theology and philosophy of St. Thomas. Cf. Sertillanges, L'idée de création et ses retentissements en philosophie.
the relation of essence to existence or on the origin of " species." The fact is that the process by which evolution has taken place must be found in the individual generations of organisms. The principle is the involution and mutual activation of the causes: causae ad invicem sunt causae.
Here it is a question of making explicit certain indications already touched on in Section VI above. There can never be any question of an effect as such exceeding the determination or " perfection " of its adequate reasons for being--a contradiction indeed; but the reason for being is never an efficient cause alone. " There is more in the cause and the effect than in the cause alone," notes de Finance.270 To challenge the
270 Joseph de Finance, Existence et liberté, p. 263. This passage (pp. 262-3) bears citation: " L'idée de causalité instrumentale est restée trop souvent liée à des schèmes grossièrement artificialistes (le marteau, la scie, le pinceau, etc.), qui empêchent de voir en elle ce qu'elle est en effet: un essai pour répondre à cette question que pose l'expérience quotidienne comment un être peut-il donner ce qu'il n'a pas? Comment peut-il être plus que soi? (Voir la-dessus d'excellentes pages du P. Labourdette, " Le péché originel et les origines de l'homme," Revue Thomiste 1950, III, pp. 496-505, ainsi que J. Maritain, Raison et raisons, Paris, Egloff, 1947, pp. 77-82.)
" Si l'on s'engage dans cette direction, on concevra les individus comme des instruments au service de la Cause universelle, qui ne cesse par eux d'amener à l'existence des êtres en qui son idée s'exprime de plus en plus parfaitement. On peut aller plus loin et, rejoignant Lamarck par une voie imprévue, attribuer ce rôle instrumental au milieu lui-même. Mais il ne faudrait pas que l'idée, forcément analogique et inadéquate,de causalité instrumentale, nous donne l'impression d'une activité qui s'exercerait sur l'univers en lui restant extérieure. Non, dans la perspective où nous nous sommes placé, l'univers apparaît travaillé par une force interne qui le projette au delà de lui-même. Cet au-delà n'est pas en lui à la façon d'une perfection naturellement possédée, et cependant il est déjà en lui d'une certaine manière et crée en lui comme une inquiétude, une distension métaphysique. II est en lui d'abord comme la fin est dans le mouvement et c'est lui qui donne leur sens et leur élan à toutes les activités cosmiques. Mais le rapport du mobile à la fin n'épuise pas la signification de la présence intentionnelle. C'est l'efficience même des agents naturels qui se trouve par elle surélevée et ordonnée à des effets qui dépassent le niveau d'être de ceux-ci.
" La chose paraîtra moins étrange, si l'on observe que toute action de la créature est, par elle-même, position d'un plus-être ou, en d'autres termes, que la causalité de l'agent fini est essentiellement synthétique et progressive. II ne peut, dit-on, y avoir dans l'effet plus que dans la cause. Soit, mais, à moins d'admettre que la cause s'appauvrit de ce qu'elle transmet ou que l'existence individuelle n'a aucune densité ontologique, il faut ajouter aussitôt qu'il y a plus dans la cause et I'effet que dans la cause seule. Le cas est particulièrement clair dans le domaine
page 322
evolutionary idea in terms of the relation of efficient cause to its possible effect considered, moreover, from the standpoint itself of efficiency, is to misunderstand the issue entirely, for it
de la vie. Le plus determiné des fixistes n'a aucune peine à concevoir la propagation d'une espèce à partir de quelques individus et nul dans l'Ecole n'a jamais vu la moindre difficulté dans l'extension graduelle de la vie sur la planète. Or, cette extension constitue bel et bien pour l'univers un progrès dont il faut rendre compte. II y a, en toute causalité véritable, une antinomie qui differe moins qu'on le pense de celle qu'enveloppe l'idee d'évolution. Seulement l'expérience quotidienne nous impose l'idée de la causalité, tandis que l'evolution ne répond à aucune donnée immédiate. Mais l'une et l'autre sont progressives et ne s'expliquent en définitive que par la présence opérante, en tout agent crée, de I'lpsum Esse subsistens. L'évolution ne serait un scandale que pour une conception strictement aristotélicienne du processus causal, ramené à la transmission d'une forme identique-- l'existence individuelle de l'effet n'entrant pas en ligne de compte--; mais alors, centre l'intention d'Aristote, c'est la vérité même de l'efficience que l'on compromet."
This last line particularly is worth noting: " L'evolution ne serait un scandale que pour une conception strictement aristotélicienne du processus causal, ramené à la transmission d'une forme identique--l'existence individuelle de l'effet n'entrant pas en ligne de compte "; for this seems to have been the basis for Hegel's express denial of the possibility of an historical evolution such as Darwin argued for: " Die Natur ist als ein System von Stufen zu betrachten, deren eine aus der andern notwendig hervorgeht und die nächste Wahrheit derjenigen ist, aus welcher sie resultiert, aber nicht so, dass die eine aus der andern natürlich erzeugt würde, sondern in der innern, den Grund der Natur ausmachenden Idee. Die Metamorphose kommt nur dem Begriffe als solchem zu, da dessen Veränderung allein Entwicklung ist. Der Begriff aber ist in der Natur teils nur Inneres, teils existierend nur als lebendiges Individuum; auf dieses allein ist daher existierende Metamorphose beschränkt.
" Es ist eine ungeschickte Vorstellung älterer, auch neuerer Naturphilosophie gewesen, die Fortbildung und den Übergang einer Naturform und Sphäre in eine höhere für eine äusserlich-wirkliche Produktion anzusehen, die man jedoch, um sie deutlicher zu machen, in das Dunkel der Vergangenheit zurückgelegt hat. Der Natur ist gerade die Äusserlichkeit eigentümlich, die Unterschiede auseinanderfallen und sie als gleichgültige Existenzen auftreten zu lassen; der dialektische Begriff, der die Stufen fortleitet, ist das Innere derselben. Solcher nebuloser, im Grunde sinnlicher Vorstelluugen, wie insbesondere das sogenannte Hervorgehen z. B. der Pflanzen und Tiere aus dem Wasser und dann das Hervorgehen der entwickelten Tierorganisationen aus den niedrigern usw. ist, muss sich die denkende Betrachtung entschlagen." (G. W. F. Hegel, Enzyklopädie der philosophischen Wissenschaften, neu herausgegeben von Friedhelm Nicolin und Otto Pöggeler [Hamburg: Felix Meiner, 1959], p. 202, par. 249. See Stace's comments on this passage in The Philosophy of Hegel [New York: Dover, 1955], par. 434, pp. 313-315).
" Mais alors," nous disons encore, " contre l'intention d'Aristote, c'est la vérité même de l'efficience que l'on compromet."
is to make no allowance for the pre-existence of the " patient" and the repercussions of its own pre-existing organizational dispositions which may either reinforce or cancel out or modify in some startling way the dispositions which would have been established by the efficiency of the agent if its interaction partner had been a purely plastic material. Since the corruption of one form is the generation of another, and since all forms are corrupted only per accidens, it is to the final dispositions of the being corrupted that we must look if we wish to know the ontological species of the subsequent form.
This is clear from Aristotle's definition of the soul (the substantial form of a living being) through its proper subject: " If, then, we have to give a general formula applicable to all kinds of soul, we must describe it as the first grade of actuality of a natural organized body," 271 where the " natural organization " in question is simply the microstructural dispositions which will necessitate the eduction from matter of a form with the faculty of replicating itself--matter organized in such a way as to enclose the capacity for life. For " unity has many senses (as many as ' is ' has), but the most proper and fundamental sense of both is the relation of an actuality to that of which it is the actuality," 272 as the pupil plus the power of sight constitutes the eye.
The whole question turns on the problem of organization. The total range of diversity in the universe of physical beings is rooted in the peculiar disposition and composition of parts in each unity, that is, in the individuating disposition; but because there are four irreducible levels of material existence, this individuating disposition must also always include a specifying disposition.
Living bodies, as all natural bodies, are fashioned out of pre-existing matter, i. e., out of the potentiality in each thing to be converted, remotely or proximately, into something radically different. Thus, considered in itself, life pertains to
271 Aristotle, De anima, Bk. II, ch. 1, 412 b 4-6.
272 Ibid., 412 b 8-9.
the potency of matter. Per se, the organization specific of life (realizable according to countless concrete modes) belongs to inorganic matter only after the manner of an inadequate or remote potentiality; per accidens, however, it may under given conditions pertain to it adequately, i.e., causally.
This is the basis for the prior possibility in principle of so-called " equivocal generation ": the origin of living matter out of non-living matter by reason of a fortuitous dispositioning of the latter in a chance (or laboratory controlled) series of causes. That this is possible follows from the very nature of the soul as the first act of a body disposed through organization to sustain in being the operations of life. It does not matter by what agencies this organization is effected: the sole condition essential and primary for educing a soul (= for constituting a living being) is the production of an organization suited to life; the actual processes through which this organization is constituted are accidental and purely secondary considerations. A univocal cause is always proportioned to its effect, either in the sense of belonging to the same irreducible ontological level, or in the sense of belonging to a higher order, such that it contains the ontological species of its effect within itself eminently. An equivocal cause, on the other hand, need not be proportioned to its effect except per accidens, in the general way that any material substance is able to act on another by very reason of belonging to a common ontological genus. In this way, as the investigations of biochemistry sufficiently indicate, the structures of the living world are potentially latent throughout the whole of secondary matter;273 for which reason again a concatenation of special circumstances could efficaciously though in a per accidens way disposition the specific (ontologically specific) organization of a living being which otherwise pertained to any one of the circumstanced
273 E. g., consult N. H. Horowitz, " The Origin of Life," in Frontiers of Basic Science, E. Hutchings, ed. (New York: Basic Books, 1958); S. Huang, " Occurrence of Life In the Universe," American Scientist, 47 (September, 1959), pp. 397-402, Albert Ducrocq, The Origins of Life (London: Elek). Two works in this area are fundamental classics: A. I. Oparin, The Origin of Life on Earth (3rd ed.; New York: Macrnillan, 1957); and L. J. Henderson, The Fitness of the Environment (Boston: Beacon, 1958). See also Gredt, fn. 1 p. 349, n. 408, pp. 342-3.
entities only potentially and indeed inefficaciously. In such a case, there would be no violation of the principle of causality and no need for a " special" divine concursus (still less intervention) , any more than there are instances of either of these in our everyday experience.274 The soul is but the first actuality of a disposed physico-chemical structure.
From an experimental point of view, it is only a superficial difference in kind. " Since in the two cases the empirical conditions are different, the phenomena themselves differ: that is all that the scientist finds." 275
From an explanatory and ontological point of view, it is a radical difference in kind, an irreducible ontological level or zone which will fill itself up with novelties until the opening of a still further zone is required by the very exuberance of the vegetative forms.
The fact that the relationship of the mechanistic to the autonomous process components is dependent upon, and therefore largely patterned after, the physical relationship of macrovariables and micro-states has been the origin of many of the difficulties and misconceptions which have arisen in biological theorizing. The tendency of so many investigators who are concerned with specific macroscopic mechanisms to make short shrift of any organismic concepts, and to generalize mechanistic views too readily beyond their original limits, can no doubt be traced to this source.276
" We are equally far removed from a pat mechanism as from an intrinsically dualistic vitalism ";277 and yet, like De Koninck's imaginary intelligence contemplating the earliest
274 De Finance, loc. cit. (see fn. 270 supra).
275 Sertillanges, L'idée de création, p. 147.
276 Walter M. Elsasser, Atom and Organism, A New Approach to Theoretical Biology (Princeton: The University Press, 1966), p. 106. On the preceding page, Elsasser exactly observed that " to consider the organism apart from its mechanistic components and functions is patently absurd. This is such a fundamental fact that one must be quite sure not to mistake it for an implicit guarantee that mechanistic biology will be successful by itself." Cf. Jacques Maritain, " Ontology and Empiriology in the Study of the Living Organism," in The Degrees of Knowledge, pp. 192-199. According to Maritain, the " ontological and philosophical knowledge of the living thing " has as " part of its task to root out the double illusion of mechanism and vitalism." (p. 198)
277 Ibid., p. 60.
page 326
stages of the process, we recognize the inevitability of life once constituted to rise--barring catastrophe--by the steps of historical novelty and by multifarious and weaving paths leading through a maze of natural forms through a taxonomic hierarchy to the rational animal; and we recognize within the 1,600,000 plus types of animals (including here the 800,000 plus types of insects which in an ontological no less than in a strictly biological optic are modes of animality: sentire in sentibus est esse) and 200,000 plus types of plants called by the taxonomist " species " another order of species and another hierarchy, the perfect hierarchy of essential forms.
We see, therefore, how the problem of the " higher " from the " lower " poses itself within the order of ontological grades. It is a mistake and a complete misunderstanding to state the issue in terms of dogs generating humans or butterflies generating mice. The authentic philosophical question is whether there is some form of physico-chemical organization which could under some circumstances be so disposed by the cosmic agents environing it as to require the eduction of a living form; and beyond that a question of whether there is any form of vegetative life which could under some circumstances give rise to some form capable in however imperfect and rudimentary a way of sensitive life. And from the standpoint of the definition of the soul through its proper subject and the involution of the causes, it is impossible to say that an affirmative answer to this question involves a contradiction. By reason of the fact that the ontological species can only be realized in individuals historically and contingently constituted, it is impossible to assign to these species absolute limits. This is the essential error in the distinction between natural and systematic species as it is commonly drawn by philosophers. " What De Koninck calls the absolute species are ordered hierarchically, but within each sphere of the hierarchy--which, because of the intrinsic indetermination and contingency of these forms is a zone of probability--there is a continuum of sub-species, varieties, or races which are only ' statistical entities.' " 278
278 Adler, The Problem of Species, p. 82.
Finally, we see just what are the philosophical dimensions of the origin of species. The principle of hierarchy, which governed traditional thought in this matter without all its main implications being recognized at once, stated that, since nature is of a hylomorphic constitution, there are a number of essentially distinct kinds in the world of physical things, and these specific natures are ordered in a perfect hierarchy by reason of the nature of essential constitution. This principle of hierarchy excludes a single all-embracing continuum, but it allows for a plurality of continua that permit a lower kind to approach the next higher by a scale of degrees. Nonetheless, the recognition that we not only know quiddities other than man but know them quidditatively, all that there are--this became possible historically only thanks to the massive labors of evolutionary research which forced the ambiguities and uncertainties of traditional discussions to the fore. Speaking from a traditional point of view and in strictly traditional terms, it became possible to say: " Every real [in the sense of essential] definition we possess has a natural species for its object; and for every natural species that there is we possess a real [essential] definition. Only singulars or accidental units escape our dianoetic intellection. These are truly infra-intelligible for the human mind, but no specific essence is."279 Once the symbiosis of epistemology and ontology in the statement of the traditional problematic was recognized, it became possible to free the ontological analysis in its own line; and this, coupled with fidelity to the principle of parsimony, made it necessary to acknowledge that the question as to what are the several real essential definitions we possess is answered by naming the universal concepts which we can define adequately, immediately below which in the order of concepts occur those which we cannot so define; and that since our knowledge of such things as gold and mercury, lion and dog, oyster and elephant, by all accounts, goes no further than nominal and descriptive definitions within the order of
279 Ibid., p. 41.
page 328
perinoetic intellection, since in addition it is impossible to arrange our real descriptive definitions of these things according to the principle of perfect hierarchy, it is impossible to respect the principle of parsimony and still contend that these things either are real species or that our knowledge of them justifies regarding them as approximations to and substitutes for the putative multiplicity of infra-human groupings of infima specific constitutions. In fact, there is no evidence for such multiplicity.
Contingency and dynamism are certainly central in the Aristotelian philosophy of nature. It is fundamentally a philosophy of change. Nevertheless, it must be admitted that Aristotle is primarily concerned with the dynamics of change in the individual subject, and not with the dynamism of nature itself, as having a career in which variegation occurs in time. To this extent, the post-Darwinian criticism is justified. Partly the failure is due to cultural circumstances, which made it difficult, if not impossible, to distinguish sharply enough between the two meanings of " species "; even if Aristotle and St. Thomas had explicitly drawn the line between Species and Race [i. e., sub-species in the ontological sense or species in the biological sense], they could not have fully appreciated its implications for the dynamism of nature, because they were ignorant of facts which have been discovered by later research. A real addition to Aristotelian truth is, therefore, possible, an addition which develops hylomorphism in the direction of its own central principles. The result is a richer and sounder philosophy of change, which embraces not only the careers of mutable individuals, but the temporal course of nature itself in all its infra-Specific variability. As there is growth and change in the individual between generation and corruption, so between creation and the end of time, there is the maturation of the world itself. Created nature has grown and developed, has flourished and decayed, in the course of generations; and the basic principles of this history, with its partially unpredictable future, are two: the potentiality of matter and the contingency of form.280
In the light of these clarifications and rectifications, and speaking within the matrix of essential principles and their implications rather than within the perspective of textual and
280 Ibid., p. 273.
historical analysis alone, we must say that " for Aristotle, the fundamental reality is the hierarchy and discontinuity of species, though he also acknowledges the appearance of continuity in the ascending scale of degrees of vitality by which we pass from lower to higher forms of life; and, in addition, as an empirical biologist, he candidly confesses the difficulty of determining whether a particular specimen is to be classified as a plant or as an animal." 281
To summarize. If by species you mean what is fixed in such a way as to be open to no differentiation beyond individual traits, then there are no species. If by species you intend existentially differentiated natural populations, then there are as many species as the conditions of genetic transmission, environmental stability, and historical interaction give rise to--well over a million at current count. Finally, if by species you understand a type or grade of being irreducible in a hierarchy by reason of a formal difference, a type so related within the hierarchy as to be unilinearly situated as higher or lower than the ones immediately below or above by the addition or subtraction of a unit difference peculiar to that one step of gradation in the natural hierarchy--an irreducible level of intelligibility which admits of no intermediate stage--then there are but four species: corporeal substance, living corporeal substance, sensitive corporeal substance, and rational sensitive corporeal substance; for only these four notions taken as types of being can be so defined inductively that their respective differences differentiate every inorganic composite, the highest (most active) as well as the lowest, from every plant, the lowest as well as the highest; and so on for plants and animals, animals and men.
But according to which of the two legitimate senses of species you have in mind, you must conceive of the hierarchy of nature differently, for it is differently on the two accountings: in the hierarchy of historically constituted populations differing really and substantially among themselves according to typical and (relatively) constant genotypic frequencies and phenotypic
281 Adler, The Difference of Man and the Difference It Makes., p. 302.
syndromes, the least animal is not differentiated from the highest plant by the addition and subtraction of a unit difference peculiar to that one step of speciation in the hierarchy-- indeed the step as such is not there, and it is difficult or impossible to assign a sense to the terms here. " The terms ' higher' and ' lower' do not mean the same thing for the scientist and the philosopher. . . . They cannot be applied to the details of specific classification. . . . Consequently, he [the scientist] does not address himself to the question: how in evolutionary science, could the higher forms come from the lower forms? "282
On the other hand, even from the philosopher's point of view, this question, if properly posed, " though it offers some difficulties, . . . does not occasion a real stumbling block." 283 In the hierarchy of irreducible grades or spheres of being, each of the levels is not only different in the way it surpasses the activities of corporeal nature but also according to the unique and contingent way in which the historical populations sub-realized as statistical entities within these probability zones or levels (dimensions, even) exceed their proximate inferiors under one aspect and are exceeded by them under another; yet the hierarchical ordering of the ontological zones as such interrupts the ordering of the interaction-structured population species, for no population species as such is ever differentiated, so far as is known, by the addition and subtraction of a unit difference.
In short, it was at its time premature and is in our time hopelessly obsolete to subscribe to John Dewey's contention that, with respect to the traditional concerns of philosophy turned toward nature, " the greatest dissolvent in contemporary thought of old questions, the greatest precipitant of new methods, new intentions, new problems, is the one effected by the scientific revolution that found its climax in the ' Origin of
282 Nogar, The Wisdom of Evolution, pp. 320-21.
283 George P. Klubertanz, " Causality and Evolution," The Modern Schoolman, XIX (November 1941), p. 12. See further Nogar, " Higher from Lower " in The Wisdom of Evolution, pp. 320-324.
Species.'" 284 The truth of the matter has been stated much less extravagantly and much more accurately by Raymond Nogar. Distinguishing sharply between natural species as essences and natural species such as are intuitively recognized in the sensible world, Nogar observes that " the divisions between substances and accidents, composed and simple bodies, the living and the non-living, the sensible and the non-sensible, the rational and the irrational, do not carry the analysis very far into the matter of natural species. They do not tell you the difference between the paramecium, the mollusk, the toad, the flamingo, the camel and the cat." 285 " Contemporary science does not use these criteria of higher or lower for the simple reason that they cannot be applied to the details of specific classification. Which is a ' higher' form, the beetle, the grasshopper, or the honeybee? It is not that the metaphysical grades of perfection are not valid philosophical categories of the general divisions of being; the scientist just has not found them useful in his methodology." 286
IX. Conclusion
What are we to conclude from the foregoing discussion? We began this investigation by posing for ourselves the question of whether the recent discoveries in science, especially the refinements on Darwin's theory of evolution, did not demand, as John Dewey and many other contemporary thinkers contended,287 a radical change in the conception of the nature of philosophical thinking?
For many post-Darwinian thinkers, only a philosophy imperfectly aware of its nature and function would claim to be more than an intellectual expression of the aspirations and ideals of a particular culture. Philosophy was born and reared in the emotional and social life of mankind evolving, and that
284 John Dewey, art. cit., p. 19.
285 The Wisdom of Evolution, pp. 328-9.
286 Ibid., pp. 320-21.
287 See Philip P. Wiener's Evolution and the Founders of Pragmatism (New York: Harper, 1949).
is precisely where it must remain. Thus " metaphysics " is the name of philosophy so close to the Greeks in (cultural) aspiration and (cultural) ideal that it has not gotten around to really meeting Darwin--or to realizing that any attempt to discern the fundamental structural features which the intelligibility afforded by the world postulates as its necessary condition (" its condition a 'priori," as some would have it) is futile and unrewarding, to say nothing of culturally obsolete. Now it is certainly true that ancient and medieval philosophy in its most formal reflections concerned itself with discerning evidence for precisely this last sort of inquiry. And it is equally true that the question as to whether or not there is a metaphysical dimension to man's awareness of the world is the same as the question as to whether or not this task is proper and possible. But, in the perspectives of these classic assessments, what was the focus, the specifying concern, as it were, of the general metaphysical problematic? In the Aristotelian-Thomistic tradition the answer to this is forthright:
The question which was raised of old and is raised now and always, and is ever the subject of doubt, viz. what being is, is just the question, what is substance? For it is this that some assert to be one, others more than one, and that some assert to be limited in number, others unlimited. And so we also must consider chiefly and primarily and almost exclusively what that is which is in this sense.288
Dewey is not the first nor will he be the last to proclaim the futility of such a consideration, and to do so in the name of " evolutionary science "; and yet, in the light of the question as posed by Aristotle, it is incumbent on those who would relativize philosophy in terms of the cultural state of scientific progress and who would accordingly see in philosophy no more than an effort to draw out the ultimate implications of scientific theories in terms of " world-view," to demonstrate and not merely proclaim that the data of evolutionary science render
288 Aristotle, Metaphysica, VII, ch. 1, 1028b1-7; St. Thomas, In VII Met., lect. 1, esp. nn. 1246 and 1260-1264. This, of course, is not to say that the formal subject of Metaphysics is ens per se or substantia rather than ens commune: see reference in fn. 290 below, and the discussion in fn. 188 supra.
all question of being in terms of substance and all substantialist interpretation of nature radically inept. Only then would their position be a reasonable and not authoritarian or dogmatic one; for it can hardly be claimed that evolution renders metaphysics in the traditional sense " impossible " and outdated by time if an empirically sound assessment of the materials on which evolutionary thought is primarily based can be shown to be in accord with the basic insights of an act/ potency analysis of substance. There is an alternative to the assessments current among many thinkers, no less fundamental, but less extravagant.
We have only begun to see the implications of hylomorphism . . . in the light of modern scientific research. We must estimate our intellectual responsibilities in terms of our concrete historic position in a developing culture. Certainly, the work of philosophy is not yet finished; on the contrary, there is evidence that we may be entering on a fresh historic moment when, after the frustrations and confusions of the first few centuries of modern times, we may be able to reap the fruits which belong properly to a culture in which science finds its place alongside philosophy and theology in the fulfillment of human enlightenment. A fruitful rapprochement between natural philosophy and the natural sciences is just becoming possible, after years of misunderstanding and destructive feud, and such promise bears directly on the remaining difficulties in the problem of species. . . . These very difficulties lie directly in the path of an advance in philosophical thought,--an advance which promises to be the characteristic achievement of our epoch in the centuries to come.
We need not wait, however, for the burgeonings of time. There is immediate work to be done. ... In all of these matters it may be too early to accomplish more than a partial clarification and a qualified resolution of the problems, but the more definitely we understand these problems the better we have performed the work that seems allotted to our day. We are living at a time when the main philosophical task is to clear away the accumulated underbrush which obscures the field of vision. . . . The problems are genuine, there is work to be done in philosophy; and at least, one can hope that the brilliant past of the traditional doctrine contains the secret which, if wisely read, will lead to an equally brilliant future.289
289 Adler, The Problem of Species, pp. 277-9: passim.
Is an understanding of the world at all possible which is not in every way bound to the cultural state of scientific progress, or, more generally, a pure function (more or less perfectly aware of itself as such) of the level of historic consciousness attained by a given cultural epoch? That is the larger question. This essay has not attempted to deal with it directly,290 except to make it clear that the problem of specific structures framed by modern biology is not a problem too dark to be illumined fundamentally by the essential principles of the metaphysics and natural philosophy of the scholastic tradition; so that, consequently, whether or not one considers it in the end impossible to transcend " even in thought " 281 space-time in general and the temporality and historicity of our socio-cultural existence in particular, at least there is nothing in the materials of evolutionary science which at the present time gives the lie to this critical contention of Jacques Maritain: " The whole structure of the experimental science of the ancients has doubtless crumbled and its collapse may well appear to anxious minds to spell the ruin of everything the ancients had thought. But in reality, their metaphysics and their philosophy of nature, in their essential principles at least (as they can be gathered from the Thomistic synthesis), have no more been affected thereby "292 than the intelligibility of a
290 I have however dealt with this " larger question " directly, or ' in its own terms,' in another essay, " Finitude, Negativity, and Transcendence: The Problematic of Metaphysical Knowledge," Philosophy Today, XI (Fall 1967), pp. 184-206; and it may be noted that this present essay is but the amplification and (to that extent) demonstration of two points mentioned in passing in this other essay, on pp. 191-2 ad fn. 30 and in fn. 32 p. 203, respectively.
291 The view, of course, of Teilhard de Chardin, repeated throughout his works but here cited specifically from The Future of Man, trans. Norman Denny (New York: Harper, 1964), p. 214; a genre of view developed with marvelous incoherence and indifference to any requirements of strict logic--to cite but one prominent example--in Leslie Dewart's The Future of Belief (New York: Herder, 1966). (Other like examples from the " Death of God " movement are cited by Mortimer Adler in his recent study of The Difference of Man and the Difference It Makes, fn. 2, p. 363; cf. also pp. 284 and 292.)
292 The Degrees of Knowledge, p. 60; cf. also fn. 1, p. 224. At the same time, we ought to note that, at one place at least in his writings, Maritain gives explicit indication as to how he thinks this cited contention ought to be verified in terms of evolutionary biology: see the section on " Substantial Forms and Evolution," pp. 35-8 of the essay " Philosophical Co-operation and Intellectual Justice," in The Range of Reason (New York Scribner's, 1952), pp. 30-50. We ought to note this, because, so far as I am able to judge, although this present essay has come to share Maritain's conclusion, it has done so along lines of analysis largely at variance with and often opposed to those lines Monsieur Maritain himself would have pursued in seeking to illustrate the conclusion in question in the particular area of biological evolution.
manuscript is affected by being written first in pencil and then in ink.
Far from destroying the very possibility of metaphysics, it is possible--as the foregoing analyses have indicated--to illustrate and justify this contention in the very terms of the present state of research in the particular sphere of evolutionary science. It is even possible--if Sertillanges is to be trusted --to go as far as Père Teilhard de Chardin, and consider that " Aristotelian hylomorphism represents the projection, upon a world without duration, of modern evolutionism. Rethought within a universe in which duration adds a further dimension, the theory of matter and form becomes almost indistinguishable from our contemporary speculations on the development of matter." 293
293 Teilhard de Chardin, Oeuvres, Vol. III, p. 181. Cited by A.-D. Sertillanges in L'Univers et I'âme (Paris: Ouvrières, 1965), p. 38.
ANALYTICAL OUTLINE
PART I (January, 1969)
PREFATORY REMARKS (Concerning the Problem of Evolution as an Illustration of the Historical Conflict Between Modern Science and Traditional Philosophy) -- p. 75
I. THE STATE OF THE QUESTION
A. Incommensurability of the Species Problematic of Modern Science with that of Traditional Philosophy -- p. 76
B. Textual Illustrations of this Incommensurability -- p. 76
1. Texts respecting the problem of species as posed by traditional philosophy -- p. 77
2. Texts respecting the problem of species as posed by modern science -- p. 77
C. Statement of the Properties of the Notion of Species Entertained by Traditional Philosophy -- p. 79
1. Relation of the philosophical notion of species to the problem of inductive verification -- p. 82
2. Relation of the philosophical notion of species to a notion of hierarchy in nature -- p. 83
D. Statement of the Properties of the Notion of Species Entertained by Modern Science -- p. 84
1. Relation of the scientific notion of species to the problem of inductive verification -- p. 86
2. Relation of the scientific notion of species to a notion of hierarchy in nature -- p. 87
E. Contrast of the Consequences of the Two Notions of Species --p. 89
1. With respect to hierarchy in nature -- p. 89
2. With respect to the formal determinateness of specific distinction -- p. 89
F. Statement of the Problem of Assessing the Implications which the Scientific Notion of Species has for the Philosophical Notion, and Vice Versa -- p. 90
II. APPROACH TO THE PROBLEM
A. The Methodological or " Logical" Dimension of the Problem -- p. 90
page 337
B. The Analytical or " Categoreal" Dimension of the Problem --p. 91
1. In terms of modern genetics and ecology -- p. 91
2. In terms of essence and existence -- p. 92
3. In terms of the necessary proportion between cause and effect -- p. 92
C. The Physico-Mathematical or " Empiriological" Dimension of the Problem --p. 93
III. THE LOGICAL OF RATIONAL UNDERSTANDING
A. The Alternative Approaches to the Problem of Understanding Nature -- p. 93
B. The Notion of Methodological Behaviorism and Its Bearing on the Problem at Hand -- p. 94
C. The Necessary Steps of "Methodological Behaviorism" -- p. 95
1. The sequence of investigative questions -- p. 95
2. The nature of explanation -- p. 96
a. The notion of factorial analysis -- p. 97
b. The correlation of structure and function -- p. 99
c. The role of the principle of parsimony-- p. 99
D. Statement of the Import of the Concept of Methodological Behaviorism on the Definitions of Science and Philosophy -- p. 100
E. " Methodological Behaviorism " as the Form of Rational Understanding-- p. 101
IV. THE FRAMEWORK OF EVOLUTIONARY SCIENCE
A. Statement of Expectations Generated by the Notion of Methodological Behaviorism---p. 102
B. Verification of Expectations -- p. 103
1. Respecting the history of evolutionary science viewed in terms of the four scientific questions -- p. 103
2. Respecting the contemporary organization of evolutionary research in terms of the four causes -- p. 104
C. Resolution of Difficulties -- p. 107
1. Difficulties arising from the meanings of terms -- p. 107
2. Difficulties arising from the focus of evolutionary studies on populations rather than on individuals as such -- p. 108
a. The two anti-chance factors in evolution -- p. 110
b. The lability of populations presupposes the stability of individuals -- p. 111
page 338
D. Consideration of the Sense in which Evolutionary Studies Meet the Ancient Requirement that Science is of the Necessary -- p. 112
1. The " quasi-syllogistic " leading to the idea of evolutionary or " natural " selection -- p. 112
2. Digression on the historical conflict between modern science and traditional philosophy over the permanence of species -- p. 118
3. Diagram of evolutionary studies as constituting knowledge of a reasoned fact, or science in the classical sense -- p. 127
4. Evolution as a transcendental property of the interaction situation-- p. 128
V. SPECIFIC STRUCTURES IN AN EVOLVING WORLD
A. The Noetic Aspect of the Darwinian Revolution -- p. 130
B. The Ontological Aspect of the Darwinian Revolution -- p. 132
1. The " family quarrel" between Linnaeus and Darwin over the fixity of forms -- p. 133
2. The problem of the criterion of metalogical species status -- p. 134
3. Realistic vs. subjectivistic approaches -- p. 136
C. The Causal Status of the Natural Groups or Kinds Indicated in the Everyday Experience of Mankind -- p. 138
1. The two senses (multiplication vs. transformation) of the question of specific change -- p. 138
2. The problem of species in terms of the interaction structuring of natural groups -- p. 139
3. The subjectivism of contemporary philosophy in conflict with the spontaneous realism of evolutionary science -- p. 145
4. The three main stages or levels in the establishment of species -- p. 147
a. The essential feature of the process of speciation -- p. 147
b. The essential feature of the species as such -- p. 147
c. The inapplicability of an " essential definition " in the traditional philo-sophical sense to the species discerned by genetic analysis -- p. 148
PART II
(April, 1969)
VI. THE ERROR OF UNIVOCALLY ONTOLOGIZED KIND-ESSENCES
A. The Contention to be Developed -- p. 251
B. Socio-Cultural, Philosophical, Theological, and Psychological Sources of the Ambiguities in the Traditional Notion of
Species -- p. 2521. Socio-cultural source: the doctrine of the celestial spheres -- p. 253
2. First philosophical source: equivocation in the notion of essence as applied to the diversities in nature -- p. 254
3. Second philosophical source: confusion of the logical and ontological usage of the term " property " -- p. 254
4. Third philosophical source: subordination of ontological to epistemological constructs in the systematic classification of natural realities -- p. 254
a. Darwin's bifurcate formulation of a three-sided issue -- p. 258
b. Infidelity on the part of philosophers to the governing principle of rational explanations, the principle of parsimony-- p. 259
5. Fourth philosophical source: confusion of the reductive with the factorial notion of the proportion obtaining between cause and effect -- p. 263
6. Theological source: interpretation of Scripture as indicating a direct and special divine intervention prerequisite to the origin of any natural species or kind -- p. 263
7. Psychological source: the human tendency to substitute authority for evidence -- p. 263
C. Explanation of the Expression, " The Error of Univocally Ontologized Kind-Essences " -- p. 264
D. The Failure of Traditional Philosophy and Contemporary Biology to Communicate in the Area of Species -- p. 264
E. The Possibility and Necessity of Such Communication -- p. 265
1. The context of causally structured history -- p. 266
2. The alteration in the meaning or sense of essentia in the contemporary as opposed to the classical species problematic -- p. 266
3. Statement of the proper task of the philosopher with respect to evolution -- p. 268
F. The Problem of Essence at the Level of Existentia ut Exercita -- p. 268
1. The transcendental transference required in order to place the question of essence in the order of " possible being " -- p. 270
2. Articulation of the present problem with the traditional question of subsistentia -- p. 270
3. Subsistence as the basic philosophical concept underlying the empirical circumscription of species as interaction-structured adaptive groupings -- p. 271
4. Digression on some historical exaggerations concerning the explanatory role played by esse in Thomistic metaphysics and natural philosophy -- p. 273
page 340
5. Essence as the concrete possibility for self-identity in the context of natural generations and corruptions -- p. 275
6. The fundamental analogy " built-into " essence as actualizable subject -- p. 276
a. Ambiguity in the use of the word " possibility " -- p. 276
b. Causality as the fundamental ground of real possibility -- p. 277
7. The historical interpretive consequence of according primary import to that which is secondary in the notion of finite being --p. 278
8. Implications of the foregoing for the question of the ontological status of taxonomic classifications -- p. 281
9. The metaphysical notion of " being-in-and-through-a-world " -- p. 282
10. Summary -- p. 284
G. The Problem of Contingency in Nature -- p. 287
H. Statement of the Problem of the Relation of Evolutionary Species to the Philosophical Doctrine of the Immutability of Essences -- p. 288
VII. THE OPERATIONAL DISPLACEMENT OF TYPOLOGICAL THOUGHT IN ITS IMPLICATIONS FOR HIERARCHY
A. The Possibility of Causal Analysis Reductive in Form -- p. 290
1. Physico-mathematics -- p. 291
2. Mechanism -- p. 292
3 Contrasts and historical roots -- p. 292
B. The Role of Reductive or " Empiriological " Analyses in the Resolution of Biology's " Family Quarrel" over Fixity of Forms -- p. 293
1. Utility of a mathematical approach to the problem of evolutionary selection -- p. 293
2. Basis of the success of the use of mathematics in biology -- p. 296
C. The False Issue over Progress Generated in Philosophy by the Tendency to Conceive Evolutionary Adaptation on a Reductivist Causal Schema -- p. 298
1. Why a reductionist conception of evolutionary selection must regard the idea of progress as contingent omni ex parte -- -- p. 300
2. That even on a reductionist conception of evolutionary selection the arrangement of forms in a hierarchy or series of hierarchies of grades and intergrades is an inevitable phenomenon -- p. 301
page 341
VIII. THE TWO HIERARCHIES
A. Clarification So Far of the Problem of the Mutual Interimplications of the Traditional Philosophical and Modern Scientific Notions of Species --p. 305
B. Issues still to be Considered in order to Resolve this Problem -- p. 305
C. Consideration of the Outstanding Issues -- p. 306
1. The issue over hylomorphism -- p. 306
2. The issue over irreducible ontological levels or grades -- p. 308
a. Analytical statement of the possible modes of difference -- p. 308
b. Collation of this analysis with the terminology of differences as " apparent," " superficial," and " radical " -- p. 309
i. The difficulty concerning radical difference in kind as viewed from the standpoint of material cause-- p. 311
ii. Resolution of this antinomy -- p. 313
c. Consequences of the analysis concerning the modes of difference -- p. 313
i. For the avoidance of reductionism -- p. 313
ii. For the relation of superficial to radical difference in kind --p. 314
iii. For the logic of definition and inductive verification -- p. 315
d. Relation of superficial and radical differences in kind to the hylomorphic structure of natural entities -- p. 316
3. The issue over the role of chance in the constitution of the world --p. 317
4. The issue over causality -- p. 318
a. The ontological criterion of evolutionary advance or progress -- p. 318
b. The inevitability of ontological development or advance -- p. 319
c. The relation and proportion of cause to effect -- p. 320
i. Meaning of the principle, causae sunt ad invicem oausae -- p. 321
ii. Particular considerations on the interdependency of material and formal causality -- p. 321
iii. The notion of " equivocal generation "-- p. 324
D. Resolution of the Outstanding Issues -- p. 325
E. Solution of the Problem of the Implications which the Scientific Notion of Species has for the Philosophical Notion of Essential Kinds --p. 327
page 342
F. Summary --p. 329
1. The two legitimate senses of the term "species" -- p. 329
2. The two notions of natural hierarchy paralleling the two senses of the term species -- p. 329
3. The true pattern of " higher " and " lower " forms -- p. 330
IX. CONCLUSION
A. The Problem of Evolution in the Context of the Historical Conflict between Modern Science and Traditional Philosophy -- p. 331
1. The allegations of contemporary thinkers -- p. 331
2. Justified vs. dogmatic allegations -- p. 332
3. An alternative assessment -- p. 333
B. The " Evolution of Species " as a Non-Illustration of a Conflict de jure between Modern Science and Traditional Philosophy -- p. 334
