Letter #3 to an Agnostic Friend: Philosophy and Science

Dear friend,

We’re going to get a little philosophical in this letter.

When I was an agnostic, I distrusted philosophy and lent it no credence. This was due to simply not having learned what philosophy was but also because in practice I heard about many different, contradictory philosophies, so I concluded that one could make “philosophy” into whatever one wanted.

But just because something can be abused and twisted doesn’t mean that it’s bad, just that it is misused.

One of the greatest thinkers to ever live was St. Thomas Aquinas. He lived during the 1200s and was a priest of the Dominican Order. He made a brilliant synthesis of how reason supports beliefs of the Catholic Faith, especially in his Summa Theologica.

He has a set of famous proofs of God’s existence from reason that are called “Aquinas’s Five Ways.” He incorporated the ancient philosophy of Aristotle and corrected and perfected it.

Here’s his first way, his argument from motion (actuality and potentiality):

1. All bodies are either potentially in motion or actually in motion.
2. "But nothing can be reduced from potentiality to actuality, except by something in a state of actuality" (419).
3. Nothing can be at once in both actuality and potentiality in the same respect.
4. Therefore nothing can be at once in both actuality and potentiality with respect to motion
5. Therefore nothing can move itself; it must be put into motion by something else.
6. If there were no "first mover, moved by no other" there would be no motion.
7. But there is motion.
8. Therefore there is a first mover, God.

This above bulleted list is from here: https://home.csulb.edu/~cwallis/100/aquinas.html

This proof then demonstrates that there is a Being, whom we call God, who is the Unmoved Mover.

To explain this more fully, God is “pure act,” and not a being that can change or become something else.

God is always already what God is. God’s existence is not dependent on anything else, and God’s perfection is not limited by potentiality or imperfection.

God is the Being whose essence is existence itself.

God’s existence is not a potentiality, but rather an actuality.

This is the preemptive answer then to the question: “Who created God?”

No one did.

The Bible in Acts 17:28 says, “In Him we live, and move, and have our being.”

There was a time when neither you nor I existed. We came into being when our parents conceived us. We are creatures, but God is the Creator.

For me, the existence of God solved many questions I never could figure out as an agnostic. For instance, where did all the energy and matter in the universe come from?

Science of course could tell us that matter/energy cannot be created nor destroyed, but it had no answer to where the energy came from or why there was energy at all.

For that matter, science is about figuring out how the universe works, like the laws of physics. We are not making up the laws of physics; rather we all recognize that they preexist us and are an objective reality that we simply, like a detective, have to try to figure out.

And as we get deeper and deeper into them, they get more wondrous rather than less: think quantum mechanics, atomic laws, and black holes.

Aquinas has four other arguments, which you can read and ponder. For me, discovering these arguments for God’s existence based on reason alone was not a compelling factor in my conversion to belief in Jesus Christ, but it is a motive of credibility in my faith now.

But for you, this may be a key realization that helps you overcome obstacles to belief in God.

Notice that believing in God as proved by reason alone does not entail that God is the Holy Trinity that Christians say God is. The Holy Trinity, that God is a unity of three Divine Persons (Father, Son, Holy Spirit) had to be revealed to us by God and must be believed through faith.

Fortunately, God is not an impersonal, cold Being, but a loving Father, and so He does love us and revealed Himself to us throughout human history, culminating in His ultimate revelation of Himself by sending His Son to be incarnate and become a man like me and you.

Alright, that’s it for today! Keep saying that one prayer per day for the grace to believe, and keep reading St. Matthew’s Gospel.

Read on for the next letter in this series, an Interlude on Baptism.