Thomas Aquinas and The Existence of God Thomas Aquinas tried to come up with a theory to prove the existence of God. Aquinas tried to prove that God exists in his first cosmological argument by using seven steps. In order to understand Aquinas’s argument you have to understand what it means to me moved. To be moved does not mean to be set in motion or physically moved from one location to another by pushing, shifting etc. To be moved means that you are changed from a state of actuality to a state of potentiality or from a state of potentiality to a state of actuality. In step number one Aquinas said “Nothing can be moved except it is in potentiality to th