Chapter 55 — That God understands all things at the same instant

From the foregoing it is also made evident that God understands all things at the same instant.

For our intellect is unable actually to understand several things simultaneously because, since the intellect in act is the thing understood in act, (Aristotle, On the Soul 3.4, 429a20–23; 3.5, 430a19–21.) if it were to understand actually several things at the same time, it would follow that the intellect is simultaneously several things according to one genus, which is impossible. And I say “according to one genus” because nothing hinders the same subject receiving different forms of different genera, even as the one body receives shape and color.

Now, the intelligible species by which the intellect is informed (with the result that the things themselves are actually understood) are all of one genus. For they have one essential nature, although the things of which they are the species do not agree in one essential nature; hence neither are they contrary to one another as are the things outside the mind. Thus it is that, when we consider a certain number of things in any way united together, we understand them at the same time: for we understand a continuous whole simultaneously, and not part by part. In like manner, we understand a proposition, and not the subject first and the predicate afterwards, because we know all the parts by one species of the whole.

From this we may gather that whatever number of things are known by one species, they can be understood simultaneously. Now all that God knows, he knows by one species which is his essence. (Ch. 46.) Therefore, he can understand all things simultaneously.

Again. The cognitive power does not know a thing unless the intention be there: thus at times we do not actually imagine the phantasms preserved in the organ, because the intention is not directed to them, for in voluntary agents, the appetite moves the other powers to act. Hence we do not consider simultaneously a number of things if the intention be not directed to them simultaneously, and those things that must come under one intention must be understood simultaneously, since he who considers the comparison between two things directs his intention simultaneously to both, and considers both at the same time.

Now all those things that are in the divine knowledge must come under one intention. For God intends to see his essence perfectly, and this is to see it according to its whole power under which all things are comprised. Therefore, God, in seeing his essence, sees all things simultaneously.

Moreover. The intellect of one who considers many things in succession cannot possibly have only one operation: for, since operations differ according to their objects, the operation by which the intellect considers the first thing must be distinct from that by which it considers the second. But the divine intellect has only one operation, which is its essence, as proved above. (Ch. 45.) Therefore, it considers all that it knows not successively, but simultaneously.

Further. Succession is inconceivable apart from time, and time apart from movement, since time is the measure of movement according to before or after. (Aristotle, Physics 4.11, 220a24.) Now no movement is possible in God, as may be gathered from what has been said above. (Ch. 13.) Therefore, in God’s thought there is no succession: consequently, whatever he knows, he considers simultaneously.

Again. God’s act of understanding is his very being, as shown above. (Ch. 45.) Now there is no before and after in the divine being, but it is all simultaneously, as proved above. (Ch. 15.) Therefore, neither is there before and after in God’s thought, but he understands all things simultaneously.

Moreover. Every intellect that understands one thing after another is at one time understanding potentially, and at another time actually: for while it understands the first thing actually, it understands the second potentially. But the divine intellect is never in potency, but is always actually understanding. (Ch. 16.) Therefore, it understands things, not successively, but altogether simultaneously.

Sacred Scripture bears witness to this truth: for it is said that with God there is no variation or shadow due to change (Jas 1:17).