This explains how God knows types, but not His knowledge of existing individuals, as John, this tree, my violin.

Incidentally, to take a favourite thought of Newman's, as all possible creation exists typically in the divine essence, so the Catholic faith contains all the truths, speculative and practical, of all religions and all moralities, minus their negations, in which, so far as they are false, their falsehood lies.

Of God and His Creatures: 1.54