Intelligence is a powerful tool. But it’s also a trap. Sometimes the bad decisions that sink great companies or end good marriages come from thinking very hard—in the wrong direction, with total conviction, and nobody around willing to interrupt. People get good at justifying irrational choices. The bad news is that the smarter you are, the better you become at making a convincing argument for what you already wanted to believe. Theoretical physicist Richard Feynman, who knew a thing or two abou