Summa summae S. Thomae sive compendium theologiae

The question proceeds concerning creatures as such, abstracting from the state of past, present, or future existence; but concerning future things there are graver difficulties, about which we speak specially below. Moreover, the resolution of the present difficulty is a prelude to the establishing or the overthrow of middle knowledge; for if God does not know things other than himself except in himself as in a cause, middle knowledge collapses; and on the contrary, if God knows things other than himself immediately in themselves, room is given for middle knowledge.

I say: God knows things other than himself, not immediately in themselves, but mediately in himself as in a cause already known.

Proof 1° from the Fathers. St. Dionysius, or whoever is the ancient author of the book On the Divine Names, cap. 7, says: « For the divine mind does not know the things that are, learning them from the things that are, but from itself and in itself, as cause, it has the cognition, knowledge, and essence of all things anticipated and comprehended beforehand: not that it considers particulars through a species, but that in one embrace of the cause it knows and contains all things.... Therefore God, knowing things, knows them not by a knowledge of the things, but by a knowledge of himself. » St. Aug., lib. LXXXIII Quaest., q. 46, says that it is a sacrilege to assert that God goes outside himself to know something. St. Thomas, weighing these words here, says they are to be understood thus: not as though God beholds nothing that is outside himself, but because that which is outside himself he does not behold except in himself¹. And he concludes the same article thus: « Thus, therefore, it must be said that God sees himself through his own essence; but he sees things other than himself, not in themselves, but in himself, inasmuch as his essence contains the likeness of things other than himself. » Understand likeness, not according to agreement in nature, but according to the representation of effects in a cause²; for the likeness of the effect pre-exists in its cause, since every agent produces something like itself.

It is proved 2° by reason. To know a thing immediately in itself is to know it through its own proper species, which represents it immediately³; but to know a thing mediately in another is to know it through the species of the other, that is, through a species that represents the other in which that thing is contained, as, for example, to know the number three in six, or an effect in its cause; for things are known in the mode and order in which they are represented through a species. But God does not know things other than himself through species proper to them, but through a species proper to himself immediately representing himself, and things other than himself mediately, insofar as they are in him as in a cause. Therefore. — The minor is proved. There is no species in God other than his own essence, as is established from what has been said above. But the essence of God, as a species, does not immediately represent creatures, but himself, and in himself the creatures, as effects contained in a cause. Therefore. — The minor is proved 1° The essence of God is, in intelligible being, per se and first, God. This is evident from the terms. But if it immediately represented creatures, God and creature would be equally in intelligible being. Therefore. 2° Immediate representation through a species comes about by reason of a likeness in nature, or an identity with the object represented. But the essence of God is neither like in nature, nor the same, with creatures. Therefore. 3° God, under the aspect of object, equals his essence under the aspect of species; for he is not less infinite under the aspect of object than under the aspect of species. Therefore, as species, it can immediately represent nothing other than God himself; the rest of things only insofar as they are contained in God. — The consequence is evident; because otherwise it would exceed, in representing, its own adequate object, which is a contradiction in terms.

Proof 3° by another reason. If God attained creatures immediately in themselves, independently of the essence seen beforehand, creatures would be, together with the divine essence, the formal and specifying object of the divine intellect; which cannot be admitted, since to be specified by something is to receive from it species and perfection. Therefore. — Proof of the inference. That is the formal specifying object which is attained per se, first, by reason of itself, and not by reason of another. Therefore.