St. Anselm's Ontological Argument

The Greater is St. Anselm’s Ontological Argument. St. Anselm was a Christian philosopher around the year 1100 A.D. His argument is based on reason alone. Rene Descartes had a similar Ontological Argument.

An interpretation of this argument goes as follows:

1. God is a being in which none greater is possible.
2. The concept of God exists in one’s mind.
3. It is possible that God may also exist in reality.
4. It is greater for a thing to exist in both the mind and in reality than in the mind alone.
5. If God exists in the mind only, then a greater than God could be thought, because one could think of God in reality, in addition to being in the mind alone.
6. It cannot be that God exists in the mind only, because God is a being in which a greater is not possible.
7. Therefore, God exists in the mind and in reality.