Is the Existence of God Self-Evident?

The speaker discusses the ontological argument for the existence of God. According to this argument, God is defined as the being that nothing greater can be conceived. If one can conceive of something greater than God, then God is not God. The speaker explains that if God does not exist, one can conceive of a God that has all the attributes of God but lacks real existence. The speaker concludes that atheism is self-contradictory because it denies the existence of a being that lacks no perfection. However, the speaker acknowledges that this argument is not valid and agrees with Aquinas in rejecting it.