To avert the slight chance that climate change will cause the collapse of human civilization? Is this potential catastrophe so fearsome that it precludes a normal cost/benefit analysis? Two Ivy league economists are dueling over this question, which Ronald Baily examines at Reason Magazine. It's not hard to see which side Baily comes down on, but in the end, he raises perhaps a much more pertinent question: why has no one ever done an analysis on the larger "probability that bad government policy will cause a civilization wrecking catastrophe."