Ontology is a branch of metaphysics that relates to the nature of being. Christian philosopher Saint Anselm of Canterbury is most known for his ontological argument for the existence of God. His argument consists of six premises. Firstly, Anselm describes God as “a being than which no greater can be conceived.” By this, he means that nothing can surpass God because he is infinitely great. However, the word “conceived” applies to the mind, meaning that God exists as an object within the mind, which is the second premise. The third premise is that being which exists in both mind and reality is greater than a being that only exists in the mind. Therefore, if God exists only in the mind, then it means that it is possible for us to conceive a being that is greater than God. This brings us back to the first premise which states that God is “a being than which no greater can be conceived.” Since we cannot imagine a being that is greater than God, it means that he must exist in both mind and reality.