Hunger to know
St. Thomas Aquinas teaches that we have a natural desire for God. This desire has its origin in our intellects, so it is not like the bodily desire for food or drink or the desire to flee from harm or lash out at someone who angers us. It is more like the hunger to know things. In fact, it arises out of our desire to know everything.
How we know
St. Thomas’ explanation for how we know things might seem odd to us, but it is worth considering. The way we know things is a consequence of the fact that we are rational animals. We are animals with rational intellects.
First, let’s look at the animal side of “rational animal.” We are like other animals in that we have senses in which we take in the world around us. We see, hear, smell, taste, and touch. Like the higher animals, we have memory, and an imagination, and can form intentions. As already mentioned, we also have bodily passions that direct us. Like other animals, when faced with danger we will fight, flee, or freeze. Like them, we play. Like them, we delight in or are disgusted by sights, sounds, smells, tastes, and touches. This is why lots of people can’t tell the difference between rational animals and non-rational animals, also why some consider their pets full members of their families.
How are we different? It is in the rational side of “rational animal.” We see the forms of things. We don’t just see a bunch of hairy four-legged creatures running around. We see cats, dogs, deer, coyotes, wolves and so on. We can abstract from the things we see what is essential to that animal, what makes it the kind of thing it is. We form the abstract concept of “catness” and “dogness” and can identify which actual things can be properly named a cat or a dog. We have an idea, which is immaterial, that lets us understand something which is material. We can also classify everything according to their forms. Really smart people can form ideas about ideas or even ideas about ideas about ideas.
St. Thomas saw—I think we must say correctly—that everything in our intellects was first in our senses. That is, we take in our experiences through our senses—but then are able to conceptualize them. So what does this have to do with desire for God?
One of the things that our rational intellects make possible is the search for the cause of any effect. Think about how many times a young child will ask “why?” about anything and everything. In our desire to know, we want to know the reason for things. The pagan philosophers could see that there had to be a First Cause, that is, something that was uncaused that had the ability to bring about all the causes and effects we experience. St. Thomas says this First Cause is what everyone calls God. With our rational intellects that can correctly perceive the essences of created things, and from them conclude there must be this uncreated thing. We can also reason out other truths about this First Cause or God, that he must be simple, his essence and existence must be identical, he must be timeless, all powerful, and good, to name a few of these truths.
So, to summarize our desire for God so far, due to the power of our intellects we can and want to know the causes of things, and our minds do not rest until we reach these causes, until we reach the cause of all causes.
But here is the problem with our natural desire to know God.
We can know that God exists and we can know things about him due to his effects in creation, but we can never know him as he is, in his essence, using reason. We can know that God or the First Cause exists, but we cannot see him. The pagan philosopher Aristotle thought, and Thomas agrees, and the Catholic Church officially teaches, that our desire for God will never rest until we can actually see God directly as he is.
The natural desire for God, then, in itself, is frustrated, because of the impossibility of the creature—however intelligent—to see God.
This is why Divine Revelation is necessary in this life. It tells us things about God that we would either not know because they are impossible to know (like God is a loving Trinity of persons), or very difficult to know (for many of us, that God actually exists). It is also why grace is necessary to help us make an act of faith in what God reveals. It is also why in heaven we will need grace—what Thomas calls the light of glory—to elevate our intellects so that we can directly (although never fully) see God.
I’d like to end with the idea of gift. Our human nature is God’s gift to us. In the gift of an intellect is the implicit desire for God. Divine Revelation and grace are gifts, too. Finally, God will offer us the light of glory so that we can see him face to face in the Beatific Vision, thus completely fulfilling the desire for God that he planted within us.
This brings us to St. Augustine’s famous saying that pertains both to the natural desire for God and Beatific vision which fulfills that desire:
You have formed us for Yourself,
and our hearts are restless
till they find rest in You. (Confessions 1:1)