Gigerenzer"s theories about the usefulness of mental shortcuts were a small but crucial element of Malcolm Gladwell"s bestseller Blink, and that attention has provided the psychologist, who is the director of the Max Planck Institute for Human Development in Berlin, the opportunity to recast his academic research for a general audience. The key concept - rules of thumb serve us as effectively as complex analytic processes, if not more so - is simple to grasp. Gigerenzer draws on his own research as well as that of other psychologists to show how even experts rely on intuition to shape their judgment, going so far as to ignore available data in order to make snap decisions. Sometimes, the solution to a complex problem can be boiled down to one easily recognized factor, he says, and the author uses case studies to show that the Take the Best approach often works. Gladwell has in turn influenced Gigerenzer"s approach, including the use of catchy phrases like the zero-choice dinner and...