Today’s Aquinas: What Does God Understand?

We’re blogging through St. Thomas Aquinas’ Compendium Theologiae, sometimes called his Shorter Summa. Find the previous posts here.

Thomas has established that God has intelligence, intellect, the ability to understand abstract concepts.  The next question is, just what is it that God understands?  What does He eternally contemplate? In Chapter 30, Thomas says,

The foregoing exposition makes it clear that God understands through no other species than through His essence.

A bit of review:  first, don’t get hung up on the word species.  In Thomas’ terminology, a species is simply a well-defined kind of thing; it doesn’t imply biological taxonomy.  In his terms, basalt is a species of igneous rock and “Craftsman-style” is a species of architecture.  Second, species is closely related to essence:  each species has an essence, which is simply what it means to be a member of that species.   You might say that the species is the lens by which we understand the object clearly.

Now, God doesn’t perceive as we do; being immaterial spirit, He has no bodily senses.  Rather, He contemplates directly; and what Thomas is saying is that the species, the lens through which God understands all that is, is simply His own essence:

The reason is, that any intellect which understands through a species other than itself, is related to that intelligible species as potency to act. For an intelligible species is a perfection of the intellect, causing it to understand in act. Therefore, if nothing in God is in potency, but He is pure act, He must understand through His own essence, and not through any other kind of species.

When I see a dog, for example, I perceive the dog’s shape and color and behavior; and I abstract from the dog I see its species, “dog”.  My intellect has the ability, the potency, to be affected by the species of the things I perceive; and it is by taking in that species that I am able to reflect on what the dog is and how it is likely to behave.  What I understand, though in a limited way, is precisely the essence of that species: what it means to be a dog, what makes dogs different from other animals.

But I am not always reflecting on dogs.  The rest of the time my intellect is in potency with respect to the species dog.  But God, being pure act, is not affected by external species in this way.  And the only “species” (though it is only a species by analogy) that is directly available to Him, as it were, is His own essence.

In consequence of this, He directly and principally understands Himself. For the essence of a thing does not properly and directly lead to the knowledge of anything else than of that being whose essence it is. Thus man is properly known through the definition of man, and horse is known through the definition of horse. Therefore, if God understands through His essence, that which is directly and principally understood by Him must be God Himself. And, since God is His own essence, it follows that, in Him, understanding and that whereby He understands and that which is understood are absolutely identical.

So God contemplates Himself and understands Himself perfectly.

Two observations.  First, this doesn’t mean that God cannot understand the things of creation; for all created things are an expression of the perfections of God as He understands them.  They all flow from God in His infinite perfection.  Second, if you ponder the relationship between a thing understood and the same thing spoken, you’ll begin to see why the Second Person of the Trinity is referred to as the Word of God.

photo credit: Public Domain; source Wikimedia Commons