Thomas Aquinas - Summa Theologica, Part I (Prima Pars)

Obj. 2: Further, Boethius says (De Trin. ii) that "a simple form cannot be a subject." But God is the most absolutely simple form, as shown (Q. 3): therefore He cannot be a subject. But everything about which an affirmative proposition is made is taken as a subject. Therefore an affirmative proposition cannot be formed about God.

Obj. 3: Further, every intellect is false which understands a thing otherwise than as it is. But God has existence without any composition as shown above (Q. 3, A. 7). Therefore since every affirmative intellect understands something as compound, it follows that a true affirmative proposition about God cannot be made.

On the contrary, What is of faith cannot be false. But some affirmative propositions are of faith; as that God is Three and One; and that He is omnipotent. Therefore true affirmative propositions can be formed about God.

I answer that, True affirmative propositions can be formed about God. To prove this we must know that in every true affirmative proposition the predicate and the subject signify in some way the same thing in reality, and different things in idea. And this appears to be the case both in propositions which have an accidental predicate, and in those which have an essential predicate. For it is manifest that "man" and "white" are the same in subject, and different in idea; for the idea of man is one thing, and that of whiteness is another. The same applies when I say, "man is an animal"; since the same thing which is man is truly animal; for in the same suppositum there is sensible nature by reason of which he is called animal, and the rational nature by reason of which he is called man; hence here again predicate and subject are the same as to suppositum, but different as to idea. But in propositions where one same thing is predicated of itself, the same rule in some way applies, inasmuch as the intellect draws to the suppositum what it places in the subject; and what it places in the predicate it draws to the nature of the form existing in the suppositum ; according to the saying that "predicates are to be taken formally, and subjects materially." To this diversity in idea corresponds the plurality of predicate and subject, while the intellect signifies the identity of the thing by the composition itself.

God, however, as considered in Himself, is altogether one and simple, yet our intellect knows Him by different conceptions because it cannot see Him as He is in Himself. Nevertheless, although it understands Him under different conceptions, it knows that one and the same simple object corresponds to its conceptions. Therefore the plurality of predicate and subject represents the plurality of idea; and the intellect represents the unity by composition.

Reply Obj. 1: Dionysius says that the affirmations about God are vague or, according to another translation, "incongruous," inasmuch as no name can be applied to God according to its mode of signification.

Reply Obj. 2: Our intellect cannot comprehend simple subsisting forms, as they really are in themselves; but it apprehends them as compound things in which there is something taken as subject and something that is inherent. Therefore it apprehends the simple form as a subject, and attributes something else to it.

Reply Obj. 3: This proposition, "The intellect understanding anything otherwise than it is, is false," can be taken in two senses, accordingly as this adverb "otherwise" determines the word "understanding" on the part of the thing understood, or on the part of the one who understands. Taken as referring to the thing understood, the proposition is true, and the meaning is: Any intellect which understands that the thing is otherwise than it is, is false. But this does not hold in the present case; because our intellect, when forming a proposition about God, does not affirm that He is composite, but that He is simple. But taken as referring to the one who understands, the proposition is false. For the mode of the intellect in understanding is different from the mode of the thing in its essence. Since it is clear that our intellect understands material things below itself in an immaterial manner; not that it understands them to be immaterial things; but its manner of understanding is immaterial. Likewise, when it understands simple things above itself, it understands them according to its own mode, which is in a composite manner; yet not so as to understand them to be composite things. And thus our intellect is not false in forming composition in its ideas concerning God.

Having considered what belongs to the divine substance, we have now to treat of God's operation. And since one kind of operation is immanent, and another kind of operation proceeds to the exterior effect, we treat first of knowledge and of will (for understanding abides in the intelligent agent, and will is in the one who wills); and afterwards of the power of God, the principle of the divine operation as proceeding to the exterior effect. Now because to understand is a kind of life, after treating of the divine knowledge, we consider the divine life. And as knowledge concerns truth, we consider truth and falsehood. Further, as everything known is in the knower, and the types of things as existing in the knowledge of God are called ideas, to the consideration of knowledge will be added the treatment of ideas.

Concerning knowledge, there are sixteen points for inquiry:

(1) Whether there is knowledge in God?

(2) Whether God understands Himself?

(3) Whether He comprehends Himself?

(4) Whether His understanding is His substance?

(5) Whether He understands other things besides Himself?

(6) Whether He has a proper knowledge of them?

(7) Whether the knowledge of God is discursive?

(8) Whether the knowledge of God is the cause of things?

(9) Whether God has knowledge of non-existing things?

(10) Whether He has knowledge of evil?

(11) Whether He has knowledge of individual things?

(12) Whether He knows the infinite?

(13) Whether He knows future contingent things?

(14) Whether He knows enunciable things?

(15) Whether the knowledge of God is variable?

(16) Whether God has speculative or practical knowledge of things? _______________________

FIRST ARTICLE [I, Q. 14, Art. 1]

Whether There Is Knowledge [*Scientia] in God?

Objection 1: It seems that in God there is not knowledge. For knowledge is a habit; and habit does not belong to God, since it is the mean between potentiality and act. Therefore knowledge is not in God.

Obj. 2: Further, since science is about conclusions, it is a kind of knowledge caused by something else which is the knowledge of principles. But nothing is caused in God; therefore science is not in God.

Obj. 3: Further, all knowledge is universal, or particular. But in God there is no universal or particular (Q. 3, A. 5). Therefore in God there is not knowledge.

On the contrary, The Apostle says, "O the depth of the riches of the wisdom and of the knowledge of God" (Rom. 11:33).

I answer that, In God there exists the most perfect knowledge. To prove this, we must note that intelligent beings are distinguished from non-intelligent beings in that the latter possess only their own form; whereas the intelligent being is naturally adapted to have also the form of some other thing; for the idea of the thing known is in the knower. Hence it is manifest that the nature of a non-intelligent being is more contracted and limited; whereas the nature of intelligent beings has a greater amplitude and extension; therefore the Philosopher says (De Anima iii) that "the soul is in a sense all things." Now the contraction of the form comes from the matter. Hence, as we have said above (Q. 7, A. 1) forms according as they are the more immaterial, approach more nearly to a kind of infinity. Therefore it is clear that the immateriality of a thing is the reason why it is cognitive; and according to the mode of immateriality is the mode of knowledge. Hence it is said in De Anima ii that plants do not know, because they are wholly material. But sense is cognitive because it can receive images free from matter, and the intellect is still further cognitive, because it is more separated from matter and unmixed, as said in De Anima iii. Since therefore God is in the highest degree of immateriality as stated above (Q. 7, A. 1), it follows that He occupies the highest place in knowledge.