Knowledge is by likeness of the mental impression to the thing known. As the likeness, so the knowledge. For a knowledge at once particular and all-embracing, there must be in the mind a likeness of all and each of the things known. But God has such a particular knowledge of all and each of His creatures, as well actual as possible (Chap. L). There must then be in God a mental likeness of each and every such creature. But whatever is in God is God's own essence, which is one and simple. How then can the one, simple essence of God be a particular likeness of each of the whole multitude of actual and possible creatures? That is the question.
Of God and His Creatures: 1.54