This is just a quick note to say that if you do not regularly read the blog The Deeps of Time, go over and read Michael's excellent post on self-existence. He compares the rational reasons behind the Thomistic belief that God is self-existing to the idea that the physical universe may also somehow be self-existing. Michael effectively shoots down the claims of some scientists (like Neil deGrasse Tyson, of whom I am a fan, as a loyal Nova viewer) that these two claims are equally reasonable.