Because my voice recorder malfunctioned 15 minutes into my Lecture on Copernicus on 2007 October 9, I've added this recording of my Copernicus lecture from Autumn Quarter 2006. It is the same basic material, but since I generally improvise on a basic outline, there will be some differences. Personally, I liked this year's lecture better, but this will at least cover most of the same material. Oh well.