While in Auburn for Mises University, I got into an argument over the existence of God. The young man arguing with me thought he had a priori proof that God couldn't exist. (We were both at the bar, so it's possible that he didn't present his case well and/or that I am botching my summary of it.) Basically he argued that theism made no sense, because if God created the universe, then that's something out of nothing. (I will pause just to let that sink in.) Naturally my first response was to say that God is not nothing. He asked, "Then what does God consist of?" I responded, "Love, wisdom, omnipotence..." It soon became clear that he was a materialist (or some variant of), and so thought that nothing could exist before the existence of the physical universe. I tried showing the problems with this by asking, "Of what does Austrian economics consist? Of what does geometry consist?" (Note that you can say propositions, but by the same t...