Did St. Anselm prove God exists? | Fr. Bonaventure Chapman & Fr. Joseph-Anthony Kress

February 26, 2026

Understanding the Ontological Argument

This Godsplaining podcast episode hosted by Fr. Bonaventure Chapman and Fr. Joseph-Anthony Kress explores St. Anselm of Canterbury’s famous Ontological Argument — a philosophical argument aiming to show that God’s existence can be deduced logically from the very concept of God. The argument begins with the idea that God is “that than which nothing greater can be conceived.” If this greatest conceivable being exists only as an idea in the mind, then a greater being — one that exists in reality — could be conceived. Therefore, by definition, the greatest conceivable being must exist in reality.

More on St. Anselm

What exactly did St. Anselm argue in his proof for God’s existence?

Anselm of Canterbury argued that God is “that than which nothing greater can be conceived.” If such a being existed only in the mind, a greater being—one that exists in reality—could be conceived. Therefore, the greatest conceivable being must exist in reality.

Frequently Asked Questions

What is the Ontological Argument in simple terms?

The Ontological Argument claims that God’s existence can be demonstrated purely through reason and definition—without appealing to physical evidence or observation.

Is Anselm’s argument based on faith or reason?

Anselm presents it as a rational argument, but he famously wrote within a framework of “faith seeking understanding.” His goal was not to convert atheists primarily, but to deepen intellectual understanding of God.

How is Anselm’s argument different from the Cosmological Argument?

Unlike the Cosmological Argument, which reasons from cause and effect in the universe, the ontological argument works entirely from the concept of God itself.