Commentaria in Primam Partem Summae Theologiae

A clear title. – In the body, a single conclusion, answering the question affirmatively: The knowledge of God is not variable. – It is proved. The substance of God is altogether immutable; therefore the knowledge of God is altogether unchangeable. – The consequence is proved: because knowledge is the very substance of God.

II. In response to the third, concerning that statement, namely, this is not true—whatever God knew, He knows—if it is referred to enuntiabilia, a doubt arises from a threefold source. First thus. Just as enuntiabilia are sometimes true and sometimes not, and therefore what was previously known is not known, so too some thing, say Socrates, is sometimes a being (ens) and sometimes not: therefore corruptible things previously known are also not known: therefore there is no difference between enuntiabilia and things in this respect—the opposite of which is had from the text. – The consequence is evident. And the proportionality is proved: because the knowable does not found truth any more than being (ens); for each thing is cognizable insofar as it is a being (ens). – And it is confirmed. Because just as God from eternity beholds the birth of Christ for such a time, so too this enuntiabile, Christ is born, for the same time; and just as He beholds the non-being of Christ's birth for other times, so too the falsity of the aforementioned enuntiabile: therefore, just as He is not said not to know the birth of Christ which He knew, so too it should not be conceded that He does not know that enuntiabile which He knew.

Second, thus. It follows most excellently: God does not know something of those things that He knew; therefore He knows fewer things than He knew. The consequent is said not to be conceded, in response to the second argument, because it involves the composed sense. The consequence, however, is proved: because the number of things known has in fact been diminished.

Third, thus. God knew some enunciable that He does not know; therefore His knowing has passed into not-knowing; therefore there is variation in the knowledge of God. Nor does the response given in the text seem sufficient, because that a judgment concerning an enunciable and one concerning a thing are not the same is what the text maintains.

III. To make this matter evident, two things must be noted. First that, for our present purpose, this is the difference between an enunciable and a thing: an enunciation, while remaining and persisting the same, changes from true to false, and consequently from knowable to unknowable, and conversely, as is clear; but a thing, if it changes from being into non-being, or conversely, does not persist. And therefore one and the same thing cannot be demonstrated, while persisting, to be now knowable and now unknowable, in the way a single enunciation can.

Second, it must be noted that the variation of God's knowledge can be spoken of in two ways. First, on the side of the act of knowing. And thus it is altogether immutable, both in act and in potency, as is said in the response to the second objection; although, speaking absolutely, the knowledge of vision could have been determined from eternity to more or fewer things. But once determined, it is altogether unchangeable on God's side. In another way, on the side of the things known. And thus, not with respect to things, but with respect to enunciables, nothing prevents it itself from changing: because this change posits no change in God, but in the enunciable known; namely, because it is changed from knowable to unknowable, and conversely.

IV. From these points, however, the answer to the objections is evident ¹. To the first, indeed, the difference between the thing and its enunciation has already been assigned; therefore it is not the same account, etc. – And in response to the confirmation, it must nevertheless be added that the thing, namely Christ's birth, determines for itself a certain time of its being (esse); but the enunciation, namely Christ is born, consignifies no determinate time, but the present in general, or indeterminately, according to the time at which it is formed or uttered. And so it is now true, and now false: because it is adequate to some present time, and not to another, while remaining entirely the same. This cannot be said of the thing, which has a certain present time of its being (esse).

To the second, however, it is conceded, with reference to the enuntiabilia, on their side. Nor did the text teach the opposite in its reply to the second: for there the discussion concerns the increase and diminution of divine knowledge on the part of God; and an increase is judged to be unfitting not only in fact but even as possible. And therefore, as far as God's side is concerned, it must be denied that He could know more than He knows. That this is the meaning of the text is clear: because it treats of God's power with respect to determining the science of vision, inferring that one ought not concede that God could know more than He knows, because of the composite sense that infers mutability on the part of God; since it infers that God's knowledge, already determined, could be changed by God.

To the third, the inference is denied, as is clear from what was said ²: because this is not due to a variation in knowledge, but in the thing known. And although the judgment about the thing and about the enunciation is not the same in respect of this, that the same thing, itself remaining intact, changes from knowable to unknowable, as was said ³; nevertheless, in respect of this, that the variation of both does not redound to a variation in the divine knowledge, the judgment is the same. And in this respect the declaration by way of similitude, drawn from the variation of things, is adduced in the text: not in respect of the first point.