Chapter 088 - How The Human Soul Knows What Is Above Itself

In our present state we cannot know separate immaterial substances as they are, either by the active or the possible intellect; for the natural intellect bears an essential relation to the nature of material things. Consequently it understands nothing except by turning to phantasms, and since separate substances are not the subject either of sense or imagination, but differ entirely in nature from material things, it follows that whatever abstractions our intellect may make from matter it can never, in its present state, arrive at anything like a conception of immaterial substances.

Thus God is not the first known to us; for if immaterial substances are not known, much less is God known; but material things are first known to us, because they are the natural object of our intellect. We arrive, however, at a certain knowledge of God through creatures, as the apostle says to the Romans: "The invisible things of God are known by those which are made."