Part 1 of a pair. Tim lays out a classic argument for the existence of God, called 'The Cosmological Argument' -- roughly, the idea that something has to explain why the world is the way it is, and that something is God. He distinguishes two versions: the Beginnings Argument, and the Modal Argument. He covers the Beginnings Argument.
Cosmological Argument Part 1
University of Mississippi
SEP: Cosmological Argument
Philosophy of Religion: The Cosmological Argument