CONTROVERSY ON THE ETERNITY OF MATTER
However, even though finished products were not in existence from eternity, we might be inclined to think that matter had to exist from eternity. For everything that has being subsequent to non-being, is changed from non-being to being. Therefore if created things, such as heaven and earth and the like, did not exist from eternity, but began to be after they had not been, we must admit that they were changed from non-being to being. But all change and motion have some sort of subject; for motion is the act of a thing existing in potency. However, the subject of the change whereby a thing is brought into existence, is not the thing itself that is produced, because this thing is the terminus of the motion, and the terminus and subject of motion are not the same. Rather, the subject of the change is that from which the thing is produced, and this is called matter. Accordingly, if things are brought into being after a state of non-being, it seems that matter had to exist prior to them. And if this matter is, in turn, produced subsequent to a period of non-existence, it had to come from some other, pre-existing matter. But infinite procession along these lines is impossible. Therefore we must eventually come to eternal matter, which was not produced subsequent to a period of non-existence.
Again, if the world began to exist after it had first not existed, then, before the world actually existed, it was either possible for the world to be or become, or it was not possible. If it was not possible for the world to be or to become, then, by equipollence, it was impossible for the world to be or to become. But if it is impossible for a thing to become, it is necessary for that thing not to become. In that case we must conclude that the world was not made. Since this conclusion is patently false, we are forced to admit that if the world began to be after it had first not been, it was possible for it to be or to become before it actually existed. Accordingly there was something in potency with regard to the becoming and being of the world. But what is thus in potency to the becoming and existence of something, is the matter of that something, as we see exemplified in the case of wood relative to a bench. Apparently, therefore, matter must have existed always, even if the world did not exist always.
As against this line of reasoning, we showed above that the very matter of the world has no existence except from God. Catholic faith does not admit that matter is eternal any more than it admits that the world is eternal. We have no other way of expressing the divine causality in things themselves than by saying that things produced by God began to exist after they had previously not existed. This way of speaking evidently and clearly brings out the truth that they have existence not of themselves, but from the eternal Author.
The arguments just reviewed do not compel us to postulate the eternity of matter, for the production of things in their totality cannot properly be called change. In no change is the subject of the change produced by the change, for the reason rightly alleged by the objector, namely, that the subject of change and the terminus of the change are not identical. Consequently, since the total production of things by God, which is known as creation, extends to all the reality that is found in a thing, production of this kind cannot properly verify the idea of change, even though the things created are brought into existence subsequently to non-existence. Being that succeeds to non-being does not suffice to constitute real change, unless we suppose that a subject is first in a state of privation, and later under its proper form. Hence "this" is found coming after "that" in certain things in which motion or change do not really occur, as when we say that day turns into night. Accordingly, even though the world began to exist after having not existed, this is not necessarily the result of some change. In fact, it is the result of creation, which is not a true change, but is rather a certain relation of the created thing, as a being that is dependent on the Creator for its existence and that connotes succession to previous non-existence. In every change there must be something that remains the same although it undergoes alteration in its manner of being, in the sense that at first it is under one extreme and subsequently under another. In creation this does not take place in objective reality, but only in our imagination. That is, we imagine that one and the same thing previously did not exist, and later existed. And so creation can be called change, because it has some resemblance to change.
The second objection, too, lacks cogency. Although we can truly say that before the world was, it was possible for the world to be or to become, this possibility need not be taken to mean potentiality. In propositions, that which signifies a certain modality of truth, or in other words, that which is neither necessary nor impossible, is said to be possible. What is possible in this sense does not involve any potentiality, as the Philosopher teaches in Book V of his Metaphysics. However, if anyone insists on saying that it was possible for the world to exist according to some potency, we reply that this need not mean a passive potency, but can mean active potency; and so if we say that it was possible for the world to be before it actually was, we should understand this to mean that God could have brought the world into existence before He actually produced it. Hence we are not forced to postulate that matter existed before the world. Thus Catholic faith acknowledges nothing to be coeternal with God, and for this reason professes that He is the "Creator and Maker of all things visible and invisible."