Israel Scheffler once told me that every time he wrote a book, he would swear it would be his last. Any author knows the feeling – books take too long to write, the arguments and the prose never seem good enough, and when one is all done, the enormity of all that is still wrong with the final product hits home. Still, authors are ever hopeful that their contributions will be of some use, and I am no exception. I have aimed to write a book that does not so much attempt to persuade, as to dissuade – I wish to shake readers loose from the grip of a conception of the world that threatens our ability to act both rationally and reasonably.

In the process of constructing a work that attempts to rattle those who read it, I have been the recipient of much help, often from people who are quite opposed to this project. I am very grateful for their generous support and probing criticisms. In particular, I would like to thank Julia Annas, John Broome, Tom Christiano, David Copp, Ron Milo, Ken O'Day, John Pollock, Joseph Raz, John Roemer, Robert Sugden, and Bruno Verbeek. I also owe much to the graduate students attending my seminars at the University of California at Davis and the University of Arizona, in which portions of this book were presented.