"We make choices all the time - about trivial matters as well as important ones that affect our lives and those of others. We also constantly judge the decisions that other people make as rational or irrational. But what kind of criteria are we applying when we say that a choice is rational and what guides our own choices, especially in cases where we do not have complete information about the outcomes? What strategies should be applied in making decisions that affect lots of people, as in the case of government policy?" "This book explores what it means to be rational in all these contexts. It shows how the theory applies to particular situations, such as whether to undergo an operation if you are told that the mortality rate is 25 per cent, the relative advantages of 'first past the post' and proportional representation in elections, and whether a country should develop a nuclear capability when it knows that others face the same choice."--Jacket.