What follows is an object lesson in not letting inspiration escape: "flights of fancy of various kinds: dancing photo vs Turing" I had just read a biography of Turing when I wrote this. I think that by "dancing photo" I meant the sort of magic photo in Harry Potter, but I'm not sure how it's a "flight of fancy". By Turing's sort of flight of fancy, I meant the ideas that lead to his universal machine. I think I was trying to point up different sorts of imagination, but I'm not sure exactly what sorts. I think that I was trying to differentiate certain sorts of formal or scientific imagination, but that rather depends on exactly what I meant about dancing photos. 12th June 2008