Some Discussion of the Question how there is in the Divine Understanding a Multitude of Objects

THIS Multitude cannot be taken to mean that many objects of understanding have a distinct being in God. For these objects of understanding would be either the same with the divine essence, and at that rate multitude would be posited in the essence of God, a doctrine above rejected on many grounds (Chap. XXXI); or they would be additions made to the divine essence, and at that rate there would be in God some accident, which we have above shown to be an impossibility (Chap. XXXIII). Nor again can there be posited any separate existence of these intelligible forms, which seems to have been the position of Plato, who, by way of avoiding the above inconveniences, introduced the doctrine of Ideas. For the forms of physical things cannot exist without matter, as neither can they be understood without matter. And even supposing them so to exist, even this would not suffice to explain God understanding a multitude of objects. For, assuming the aforesaid forms to exist outside the essence of God, and that God could not understand the multitude of things without them, such understanding being requisite to the perfection of His intellect, it would follow that God's perfection in understanding depended on another being than Himself, and consequently His perfection in being, seeing that His being is His understanding: the contrary of all which has been shown (Chap. XL). Moreover, assuming what shall be proved hereafter (Bk II, Chap. XV), that whatever is beyond the essence of God is caused by God, the above forms, if they are outside of God, must necessarily be caused by Him. But He is cause of things by His understanding, as shall be shown (Bk II, Chap. XXIII, XXIV). Therefore God's understanding of these intelligible forms is a natural prerequisite for the existence of such forms. God's understanding then of the multitude of creatures is not to be explained by the existence of many intelligible abstract forms outside of God.

1.50 : That God has a Particular Knowledge of all things
1.52 : Reasons to show how the Multitude of Intelligible Ideal Forms has no Existence except in the Divine Understanding