Commentaria in Primam Partem Summae Theologiae

A clear title. - In the body, a single conclusion answering the question affirmatively: God is altogether immutable. It is proved by a threefold argument, and by authority. First thus. God is the first being (ens): therefore pure act: therefore altogether immutable. The antecedent was proved in question II. The first consequence is proved: because act is naturally prior to potency. The second, however: because in everything mutable there must be potency. - Second thus. God is altogether simple: therefore he cannot be changed. The inference is proved: because whatever is changed is in some way composite; since it remains in one respect, namely as subject, and not in another. - Third thus. God is infinite: therefore he cannot extend or reach to something anew: therefore he cannot be moved. The first consequence is proved: because the infinite comprehends within itself the whole perfection of esse. The second, however: because whatever is changed reaches to something to which it previously did not reach. - The authority is that of the ancient philosophers who, as if compelled by truth, posited an immovable first principle.

In the title, "proper" is taken as it is distinguished against what is common; "immutable" is taken negatively, as denying every kind of mutability.

II. In the body of the article there is a single conclusion, responsive to the question in the affirmative: God alone is altogether immutable. — This conclusion, since it is exclusive, has an affirmative exponent, God is altogether immutable, proved in the preceding article; and a negative one, nothing other than God is altogether immutable; to which there is equivalent the universal affirmative with a finite predicate, or its opposite, namely, everything other than God is in some way mutable. And therefore in the text this universal affirmative is first proved; then, by way of epilogue, the proof of the whole exclusive conclusion responsive to the question is gathered together.

III. The proof of that universal affirmative, however, is made in two ways: first, with respect to the one common species of change; second, with respect to each of the parts of the universe, according to their various changes. It is proved, therefore, first, that every creature is mutable by potency in another, thus: Every creature is mutable from nothing into something, and again from something into nothing: therefore. — The antecedent is evident. The consequence is proved: because creation and conservation depend on the simple will of God.

Second, that every creature is mutable by a power within itself, either with respect to substantial and accidental being; or with respect to accidental being, such as place; or with respect to evil and good, and application to diverse things. It is proved. In every creature there is something able to persist together with the privation of substantial being, or local being, or of good, and of contact with this power: therefore. — The antecedent is evident by distinguishing the three parts of the universe: the sphere of the elements together with mixtures, the celestial bodies, and spiritual substances. The consequence is proved: because every change according to a power within itself is from being possible to be with each of two opposites successively.

IV. Concerning what is said here, note first that, when the text distinguishes passive potency into a potency for esse and a potency for the attainment of an end, the attainment of an end is not distinguished against esse in common, as if it posited no esse at all; but rather against esse in the absolute sense, which is substantial esse, as is said in Book VII of the Metaphysics¹; or against esse as it is the proper effect of the first act; for the attainment of an end consists in second act. – Note secondly that in the text, for the perfection of the doctrine, there are set down not only those things that pertain directly to the conclusion, namely those that reveal the mutability of every creature; but also those things that pertain to some immutability on their part. And since there will be a discussion of these below² by design, in their proper places, when the angels and heavenly bodies are treated, they must now be passed over. But those other things concerning immutability must be treated presently.

V. On the first part of the distinction, in the text applied to change from nothing and into nothing, etc.³, there arises a great crowd of objectors, out of ignorance of the Peripatetic philosophy. For they cannot, or will not, perceive that something created may be in itself substantially immutable, and yet mutable by potency in another: mutable, I say, in the manner explained above. And although their arguments and words are multiplied and expanded, their root is nevertheless twofold: one of reason, the other of authorities. The reason is that, taking an angel, it is asked: Either it is a possible being, or a necessary one. If possible, our point is established: for to be possibly being and non-being is not an accidental or extraneous predicate, as is said in X Metaphysics⁴; but it belongs to substance, or is in substance. If necessary, therefore it is impossible for it not to be: therefore by no power can it not be; for no power can do what is impossible. – The authority is that of Averroes, I De Caelo, commentary CXXIV, and XII Metaphysics, commentary XLI. Algazel also says⁵ that it is possible that something which exists should not be when another does not exist. It also contradicts faith to posit that anything besides God is necessary. Therefore.

VI. For the clarification of these matters, three points must be noted, from which everything pertaining to this subject, whatever objections may be raised against it, is resolved. The first is that there is a great difference between the necessary and the possible as they are differences of real being and as they are differences of true being. Insofar as they are differences of true being, they are taken logically and consist solely in the relation of terms, as is evident. But insofar as they are differences of being per se—which signifies substance, quantity, etc., as is said in V ⁶ and VI Metaphys.⁷—they are thus substantial conditions of things intrinsic to the things themselves; as is said of the corruptible and incorruptible in X Metaphys., in the last text⁸. It is one thing, therefore, to speak of the necessary and the possible as they are real differences, and another as they are differences in the relation of terms. For in this latter way they abstract from potency in itself or in another—indeed, from every potency properly so called, since they are found in mathematical entities according to no true potency, as is said in V Metaphys., in the chapter on Potency⁹, and in IX of the same work, at the beginning¹⁰. In the former way, however, it is considered according to what is intrinsic to things. Hence both the necessary and the possible must be distinguished into the real and the logical, and no confusion should be made.

Second is that the potency existing in a thing with respect to non-being, from which a thing is said to be possible, cannot—even if license to feign be granted—be posited otherwise than secondarily, namely because it exists in the thing as a potency toward another being incompossible with this being: since no potency, and no appetite, looks first to non-being, as is said in I Ethics¹¹ Hence it must be that a thing lacking a potency toward another being incompossible with this one also lacks a potency toward non-being. And since it is established that a real potency toward another being remains and is perfected in that being's advent, it follows necessarily that everything in which there is a potency toward non-being has, or is, something able to remain together with the privation of that being which it actually has. And therefore in the text it is very well said that what is possible through a potency in itself must be of such a kind, he intending the really possible. And conversely, the real necessary, which is equivalent to the immutable, is that which lacks such a potency. And hence it follows that something can be logically possible while nevertheless really necessary. Logically possible indeed: because neither part of a contradiction regarding an inherent predicate implies a contradiction; for instance, neither this proposition, the heaven is, nor this one, the heaven is not. Really necessary, however: because in it there is no potency toward another being, and consequently none toward the privation of the being it has. And we suppose here that whatever does not imply a contradiction is possible, not only logically, but by the real potency of almighty God; therefore the logically possible can also be called really possible—yet extrinsically, because through a potency in another. And for this reason in the text, where God and things are under discussion, "possible through a potency in another" was said.

Third is that what is common to every thing distinct from God is to have not this affirmative condition, properly speaking, namely not to be of itself, but rather this negative one, namely to be not of itself, because it depends on another not only in coming into being but also in being preserved; just as air is not illuminated of itself. And on account of this condition it is said that creatures are nothing of themselves, that by the nature of their origin they are defectible, and that they can not be, and many other things: all of which must be reduced to the aforesaid sense, since they posit only dependence on another in coming into being and in being preserved, and not a power in the creature for the opposite.

VII. These things having been briefly set forth, the answer to everything is now clear¹². For St. Thomas here, and in Book II of the Contra Gentiles, chapters XXX and LV, and in Question On the Power of God, question V, article 3, and everywhere else, holds that angels and heavenly bodies are real necessary beings, yet logically possible and possible through the power of another; and that God alone is necessary in every respect. — Nor does this conflict with philosophy or with faith. Not with philosophy indeed, as is now clear. Nor even with the philosophers: for they equivocate concerning the possible and the necessary, as is easily shown by induction. But to say that it conflicts with faith is the height of ignorance: such as seems to reign in our own time among certain Parisians, who regard the aforesaid chapter of St. Thomas with suspicion. But let us leave these men to their ignorance: for they are not worthy that words be spent on them in so arduous a matter.