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St Thomas and generation of water

Started by tacf, December 19, 2021, 09:00:39 AM

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That things have natures and thus act for natural ends is the basis for natural theology, because then an act that goes contrary to the end of man is definable as a sin. But this is difficult to argue to a non-catholic as they will say natures have no final cause, or that it is unknowable, or that efficient causes are not necessary to exist for motion, or that an effect can be greater than its cause (evolution), or that substantial forms do not exist, etc.
In light of this, I sought for explanations of natural events in Thomistic terms. The texts I found gave some basic examples using artificial forms (typically St Thomas' classic examples of a house and a statue), but this means I'm trying to reach a college level understanding of physics/chemistry/biology in Thomistic terms even though all explanations are given in modern terms.
So I thought I would work out what I consider a high school level/college level of explanation for the generation of water from oxygen and hydrogen in Thomistic terms. Below is that.
What I would like is corrections or references which you may think do give college level explanations (hopefully without engaging in Phd level debates).
As background, a high school/early college explanation of water generation I found:
Helmenstine, Anne Marie, Ph.D. "How to Make Water From Hydrogen and Oxygen." ThoughtCo, Aug. 26, 2020,
QuoteWater is the common name for dihydrogen monoxide or H2O. The molecule is produced from numerous chemical reactions, including the synthesis reaction from its elements, hydrogen, and oxygen. The balanced chemical equation for the reaction is: 2 H2 + O2 → 2 H2O. In theory, it's easy to make water from hydrogen gas and oxygen gas. Mix the two gases together, add a spark or sufficient heat to provide the activation energy to start the reaction, and presto—instant water. Merely mixing the two gases at room temperature, however, won't do anything, like hydrogen and oxygen molecules in the air don't spontaneously form water. Energy must be supplied to break the covalent bonds that hold H2 and O2 molecules together. The hydrogen cations and oxygen anions are then free to react with each other, which they do because of their electronegativity differences. When the chemical bonds re-form to make water, additional energy is released, which propagates the reaction. The net reaction is highly exothermic, meaning a reaction that is accompanied by the release of heat.
First, let us define terms, using the Thomistic manner of enumerating the four causes (efficient, material, formal, and final):
Hydrogen is a corporeal being, made of protons and electrons, constituted by the form given by its quantum wave function, intended for the glory of God which among other things includes serving as a part in water.
Oxygen is a corporeal being, made of protons, neutrons and electrons, constituted by the form given by its quantum wave function, intended for the glory of God, which among other things includes serving as a part in water.
Water is a corporeal being, made of hydrogen and oxygen, constituted by the form of a molecule consisting of covalent bonds between an oxygen and two hydrogen atoms, which is intended for the glory of God which among other things includes serving as nourishment for man.
The generation of water is absolute generation, as it is a substantial change, i.e., a change of the entire substance:
Aquinas, Commentary on Aristotle's Generation and Corruption, Lecture 11, 83:
Quote...the change which is "from this into this," i.e., from substance that is being in potency into substance which is being in act, is generation; while change with respect to magnitude is growth (through which something is changed from small into large) and diminution (through which something is changed from large into small); while change with respect to "passions," i.e., passible qualities, is alteration.
Aquinas, Generation and Corruption, Lecture 10, 75:
Quotewhen a change affects not only the passions but the entire substance of a thing, in so far, namely, as the matter acquires another substantial form so that nothing perceptible remains as though the being in act were the same subject as to number — for example, when from the whole seed, there is generated what is wholly blood, or when from what is wholly air there is generated what is wholly water, without any gathering or separating playing a part as Democritus posited — such a change is the generation of one thing and the corruption of another.
Since generation is a species of change, the principles of change apply.
The necessary principles of natural change are given by Summary of Scholastic Principles, Principle 104.
Quote(1) an agent, (2) adequate power in the agent, (3) contact between the agent and patient, (4) real formal dissimilarity at the start of the change, (5) passive potency in the patient for the perfection, and (6) God's concurrence.
A conceptual principle that may be useful is how a motion is considered the act of the mover and of the mobile.
Aquinas, Commentary on Aristotle's Physics 3, Lecture 5, 325:
QuoteBecause there was a doubt whether motion is an act of the mover or of the mobile and we showed that it is an act of the active as from it and of the passive as in it, then to remove any further doubts we can say somewhat more explicitly that motion is an act of the potency of that which is active and of that which is passive. In this way we could say that building is an act of the "builder" and of the "buildable as buildable"; the same is true of healing and of other motions.
We can now examine further what it means to generate water from two contacting pairs of hydrogen and oxygen. One pair, the agent, must have a substantial form, at least virtually, to generate the form of water, and the other, the patient, must have a form receptive for such a substantial change.
Examining the agent, we may ask what it means to have adequate power. In modern terms, it is kinetic energy sufficient to overcome the binding energy of the covalent bonds. The value of kinetic energy of a thing is a measure of its motion with respect to the other object, in this case the patient. Now power is synonymous with active capacity, which is a species of quality. And St Thomas says that local motion, or motion with respect to the other body, is the efficient cause of the other motions:
Aquinas, Physics 8, Lecture 14, 1088:
Quote[Aristotle] says that since there are three species of motion: one with respect to quantity and called "growth and decrease," another with respect to passible quality and called "alteration," and a third with respect to place and called "local motion,". The last one must be the first of all.
Aquinas, Physics 8 Lecture 14, 1088:
Quote... before every alteration there is a previous local motion, for if something is altered, it is necessary that there be something causing alteration, that makes the potentially hot come to be actually hot. But if this cause of alteration were always in the same way near at an equal distance to the thing altered, then it would not make it any hotter now than previously. Therefore, it is plain that the mover in alteration does not remain the same distance from what is altered, but is at one time closer and at another time farther away—and this cannot happen without a change of place.
Aquinas, Physics 8, Lecture 14, 1093:
Quote... If we consider some one body that is newly generated, local motion seems to be the last change to affect it. For first it is generated, then it is altered and increased, and finally it undergoes local motion, when it is now perfect, as is clear in man and in many animals. But this does not disprove the statement that, absolutely speaking, local motion is first in point of time, because before all those motions which are found in this generated thing, a local motion had to exist in some prior mobile, which is the cause of the generation for those that are generated, as the generator is the cause of what comes to be in such a way as not to be itself generated. That the motion which precedes generation is a local motion and that, absolutely speaking, it is the first of motions, he proves on the ground that generation is seen to be the first of motions in things that are generated, because a thing must first be made before it is moved—and this is true in everything generated. But there must be something moved prior to what is generated and which is itself not generated, or if it is generated, then there was something prior to it. In this way we must go on ad infinitum, which is impossible, as was proved above, or come to some first. But that first cannot be generation, for then it would follow that all changeable things are perishable, because everything that can be generated is able to perish. [And if all things are perishable...] Therefore, if the first mobile is something generated, it follows that it is perishable and as a consequence, all the subsequent mobiles. But if generation is not absolutely first, it is clear that none of the motions that follow it is absolutely first. And I say motions that follow, meaning growth, alteration, decrease and ceasing-to-be, all of which follow generation in time. If, therefore, generation is not prior to local change, it follows that none of the other changes can be absolutely prior to local change, And so, since some change must be absolutely first, it follows that local change is first. 1094. Then at (860) he proves that local motion is first in the order of perfection, And this he proves in two ways. First, in this way: Everything that is coming to be is, while it is coming to beg imperfect and tending to its principle, i.e., to a likeness to the principle that made it, and which is naturally first. From this it is clear that what is subsequent in the order of generation is prior in the order of nature. But in the process of generation, in all things generable, local change is found to be last, not only in one and the same thing, but also in the total progress of the nature of things that can be generated. Among these some living things are completely immobile with respect to place on account of a lack of organ, as are plants, which do not have the organs required for progressive motion, and also many types of animals. But in the perfect animals local motion is found. If, therefore, local motion is present in things which comprehend nature in a higher degree, i.e., which attain to a greater perfection of nature, it follows that local motion is among all motions the first with respect to the perfection of substance.
From this, we see "First kinetic energy must be supplied to break the covalent bonds" is a difference of words, not of concept from "first local motion results in a change in quality".
We note that the conclusion that the agent must have the substantial form of water at least virtually follows from: (A) every agent produces its like, (B) generation produces a substantial change, and (C) the substantial form is the genus for any mover in generation:
That the agent produces its like in motion is a known scholastic principle.
QuoteScholastic Principles 153: The end of generation is the form of the generated in as far as it is like the form of the generator; i.e., every agent intends some likeness of itself.
That generation is the coming-to-be of a new substantial form was explained previously.
That only a substance can be the mover for absolute generation is given by St Thomas:
QuoteAquinas, Physics 3, Lecture 4, 302: [In motion] some form is always seen to be the mover—as the form which is in the genus of substance is the mover in substantial change, and a form in the genus of quality is the mover in alteration, and a form in the genus of quantity in growth and decrease. Forms of this type are the causes and principles of motions, since every agent moves according to its form. For every agent acts inasmuch it is actual—as an actual man makes an actual man of man in potency. Hence, since it is through its form that a thing is actual it follows that form is the moving principle. Thus "to move" belongs to a thing inasmuch as it has a form through which it is actual.
One might say that if agent produces its like and neither oxygen or hydrogen is water, then there can be no generation of water. But the answer to this is that the agent must have the perfection of the final form, in this case the substantial form of water, at least virtually.
Dictionary of Schol Philos, by Wuellner:
QuoteVirtual possession of a perfection is defined as "by way of active potency or efficacy, after the manner of a cause"
And this perfection virtually present may be secondary from relations, not just the substantial form:
QuoteScholastic Principles, 256: There is only one substantial form in each natural body. But other perfections or forms of the compound may in some instances be virtually present.
That some perfections exist only virtually is not controversial; determining what is present only virtually can at times be. For example, a blind man begetting a child with sight possesses the capacity of sight virtually. Also, the eggs and sperm released from fish in the ocean possess sensitive souls virtually. St Thomas explains that human souls cannot be present virtually as they are immaterial, but animal and plant souls can as they are purely material. This is why he and others thought generation of animal souls to be possible from the purely material causes of the sun and decomposing corpses:
QuoteSumma Theologica, FP, Q70, A3, Obj 3: On the contrary, Damascene says (De Fide Orth. ii), "Let no one esteem the heavens or the heavenly bodies to be living things, for they have neither life nor sense."... Since the heavenly body is a mover moved, it is of the nature of an instrument, which acts in virtue of the agent: and therefore since this agent is a living substance the heavenly body can impart life in virtue of that agent.
Even if one disagrees with the some of this explanation, it is clear that St Thomas held to "every agent produces its like" but did not conclude that therefore the agent could not be changed with the motion. In fact, he said the agent had to if it were a corporeal agent which caused the motion by means of contact and shared the same elements (using St Thomas' definition of element):
QuoteAquinas, Physics 3, Lecture 4, 299: [In two ways it must be said that the] mover is moved. This is so first of all because anything that is previously in potency and then in act is somehow being moved. But movers are found that are previously movers in potency and afterwards movers in act; therefore they are moved. He states, therefore, that every mover, since it is such that it is in potency to being a mover, is likewise moved. This is clear from what has been already said, for it was said that motion is an act of a thing existing in potency and this occurs in every natural mover; that is why it was said above that every physical mover is moved. Secondly he brings out the same point in another way: Whatsoever's immobility is its rest is capable of motion; for rest and motion, since they are opposites, happen to the same. But the immobility of a mover, i.e., its ceasing from moving, is called rest; for there are things which said to rest when they cease to act. Therefore every such mover, i.e., one whose immobility is rest, is moved.
Then [Aristotle] shows why it happens that a mover is moved. For it does not happen precisely because it is a mover but because it is such by touching; because to move is to act in order to cause something to be moved and what is so acted upon by the mover is moved. But whatever acts does so by touching, for bodies act by touching; hence it follows that what acts is at the same time acted upon, because that which touches is acted upon. However, this must be understood of those cases where there is mutual touching; namely, when the thing touching is also touched, as happens in things which are material, where both of the things are acted upon when they touch one another. But heavenly bodies, because they do not have material like the lower bodies, so act on them that they are not acted upon in return and they touch without being touched as is stated in De Generatione I (l.18).
Examining the patient/receiver, St Thomas outlines what a passive potency for the final perfection means:
QuoteAquinas, Physics 7, lecture 5, 917: To make this clear it must be considered that a receiver can be related in three ways to a form that is to be received.
For sometimes the receiver is in the final disposition for the reception of the form and no impediments exist either in it or in anything else. Under these conditions, as soon as the active principle is present, the receiver accepts the form without any further alteration, as is evident when air is illumined, the sun being present. But sometimes the receiver is not in the final disposition required for receiving the form. In that case a per se alteration is required to put into the matter a disposition for this particular form, as, for example, when fire comes to be from air. Sometimes the receiver is in the final disposition for the form but an obstacle is present, as when air is prevented from receiving light either by closing a shutter, or by the presence of clouds. In these cases, an alteration or changed is required per accidens, i.e., the removal of the obstacle.
In this case, it would be the binding energy of the covalent bonds that has already formed the pairs of oxygen atoms and the pairs of hydrogen atoms. The value of the binding energy would be a measure of the patient's passive potency/intrinsic disposition. And this intrinsic disposition admits of degrees, as is expected for qualities (as disposition is a species of quality). No external obstacle is present. Once the binding energy has been overcome, the patient can receive the new form and water is generated. Successive changes in the qualities in the patient result in increasing aptitude for substantial to change to water. In this instance, since generation is occurring as opposed to alteration, these changes in quality are the observed changes which reflect the ongoing changes in substantial forms. This implies that there are many intermediate forms before the complete form of the species of water:
QuoteAquinas, Generation and Corruption, Lecture 6, 60: Form, however, is of two kinds: one is perfect and completes the species of a natural thing, as in the case of the form of fire or water or man or plant; the other is an incomplete form which neither perfects any natural species nor is the end of the intention of nature,  but is something on the road to generation and corruption. For it is plain in the generation of composites, for example, of an animal, that between the principle of generation, which is the seed, and the ultimate form of the complete animal, there are many intermediate generations which have to be terminated to certain forms, none of which makes the being complete in species, but rather an incomplete being which is the road to a certain species. Likewise, on the side of corruption there are many intermediate forms that are incomplete: for the body of an animal is not, as soon as the soul is separated, immediately resolved into the elements; rather this takes place by means of many intermediate corruptions in which many imperfect forms succeed one another in the matter, such as the form of a dead body, then the form of a putrefied body, and so on. When, therefore, through corruption a privation is reached that is joined to such a form in matter, there is absolute corruption in the strict sense; when, from the privation to which is attached an imperfect form which was the road to generation, there is arrival at the complete form, there is absolute generation.
Quodlibetal statements:
An active quality is that which causes a change in another. The species of quality are habit/disposition, capacity/incapacity, perceptible qualities (such as hot/cold, whiteness/blackness, sweetness), shape and those stemming from relations (i.e., rarity/density, roughness/smoothness).
QuoteSumma Theologica, FP of SP, Q49, A2: For quality, properly speaking, implies a certain mode of substance. Now mode, as Augustine says (Gen. ad lit. iv, 3), "is that which a measure determines": wherefore it implies a certain determination according to a certain measure. Therefore, just as that in accordance with which the material potentiality [potentia materiae] is determined to its substantial being, is called quality, which is a difference affecting the substance, so that, in accordance with the potentiality of the subject is determined to its accidental being, is called an accidental quality, which is also a kind of difference, as is clear from the Philosopher (Metaph. v, text. 19). Now the mode of determination of the subject to accidental being may be taken in regard to the very nature of the subject, or in regard to action, and passion resulting from its natural principles, which are matter and form; or again in regard to quantity. If we take the mode or determination of the subject in regard to quantity, we shall then have the fourth species of quality. And because quantity, considered in itself, is devoid of movement, and does not imply the notion of good or evil, so it does not concern the fourth species of quality whether a thing be well or ill disposed, nor quickly or slowly transitory. But the mode of determination of the subject, in regard to action or passion, is considered in the second and third species of quality. And therefore in both, we take into account whether a thing be done with ease or difficulty; whether it be transitory or lasting. But in them, we do not consider anything pertaining to the notion of good or evil: because movements and passions have not the aspect of an end, whereas good and evil are said in respect of an end. On the other hand, the mode or determination of the subject, in regard to the nature of the thing, belongs to the first species of quality, which is habit and disposition: for the Philosopher says (Phys. vii, text. 17), when speaking of habits of the soul and of the body, that they are "dispositions of the perfect to the best; and by perfect I mean that which is disposed in accordance with its nature." And since the form itself and the nature of a thing is the end and the cause why a thing is made (Phys. ii, text. 25), therefore in the first species we consider both evil and good, and also changeableness, whether easy or difficult; inasmuch as a certain nature is the end of generation and movement. And so the Philosopher (Metaph. v, text. 25) defines habit, a "disposition whereby someone is disposed, well or ill"; and in Ethic. ii, 4, he says that by "habits we are directed well or ill in reference to the passions." For when the mode is suitable to the thing's nature, it has the aspect of good: and when it is unsuitable, it has the aspect of evil. And since nature is the first object of consideration in anything, for this reason habit is reckoned as the first species of quality.
Energy is the capacity to cause or undergo a physical change. Capacity here being a species of quality.