IV - The Trinity Implies Creation
Man might, through reason, posit the existence of a creator god. I respond that it should be said that this is not the question whether God can be seen immediately in His essence, for this belongs to another discourse. The question is whether (God) can be known in any way at all. And so we say that God is knowable; not however that He is so knowable that His essence can be comprehended. [Aquinas, Commentary on the First Book of the Sentences of Peter Lombard, Distinction III,