The real is the rational, and the rational is the real. In philosophical discussion, no statement is, perhaps, more important or more controversial. Yet, this is the very position that I advocate within this paper. The equation of the rational with the real is at the heart of the argument I here consider, that being the ontological argument for the existence of God.There are several versions of the ontological argument for the existence of God, which is to say that several versions exist. The reason I add the redundancy about the existence of the versions of the arguments is to call attention to the fact that it is a great debate in philosophy what one means by existence and what one can and cannot say of something regarding its existence. Typically, the particular arguments called ontological arguments for the existence of God have been attacked because the argument is said to claim more about existence than can be proved about existence.An ontological argument for the existence of God typically attempts to prove the existence of God a priori, that is independent of experience via reason. Unlike the cosmological and teleological arguments which all make some first appeal to what one can observe in nature, the ontological argument begins with a definition of God and deduces conclusions which follow from the definition.In one version of the ontological argument, St. Anselm of Canterbury attempted to prove the existence of a necessarily existing being, and since Anselm others have wrestled with his famous ontological argument for the existence of God. The version of the argument I wish to consider is this:It [God] can be conceived to be something such that we cannot conceive of it as not existing. This is greater than something than which we can conceive of as not existing. Therefore, if that which than which a greater cannot be conceived [God] could be conceived not to be, we would have an impossible contradiction: that than which a gr...