Reply Obj. 1: This name HE WHO IS is the name of God more properly than this name "God," as regards its source, namely, existence; and as regards the mode of signification and consignification, as said above. But as regards the object intended by the name, this name "God" is more proper, as it is imposed to signify the divine nature; and still more proper is the Tetragrammaton, imposed to signify the substance of God itself, incommunicable and, if one may so speak, singular.
Reply Obj. 2: This name "good" is the principal name of God in so far as He is a cause, but not absolutely; for existence considered absolutely comes before the idea of cause.
Reply Obj. 3: It is not necessary that all the divine names should import relation to creatures, but it suffices that they be imposed from some perfections flowing from God to creatures. Among these the first is existence, from which comes this name, HE WHO IS. _______________________
TWELFTH ARTICLE [I, Q. 13, Art. 12]
Whether Affirmative Propositions Can Be Formed About God?
Objection 1: It seems that affirmative propositions cannot be formed about God. For Dionysius says (Coel. Hier. ii) that "negations about God are true; but affirmations are vague."
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.