Mark Greenberg

John Leslie comes to tell us that the end of the world is closer than we think. His book is no ordinary millennial manifesto, however. Leslie is a sophisticated philosopher of science, and the source of his message is not divine revelation, apocalyptic fantasy or anxiety about the year-2000 computer problem, but ‘the Doomsday Argument’ – an a priori argument that seeks support in probability theory. In fact, the most interesting questions The End of the World raises are not, despite its subtitle, about our eventual demise. Rather, they concern our susceptibility, when thinking about risk, uncertainty and probability, to a kind of cognitive illusion. The Doomsday Argument is a case-study in ‘probabilistic illusion’, for it rests on a web of insidious intuitions, hidden assumptions and seductive but imprecise analogies.’‘