Behavioral economist Dan Ariely studies the bugs in our moral code: the hidden reasons we think it's OK to cheat or steal (sometimes). Clever studies help make his point that we're predictably irrational -- and can be influenced in ways we can't grasp. It's become increasingly obvious that the dismal science of economics is not as firmly grounded in actual behavior as was once supposed. In "Predictably Irrational," Dan Ariely tells us why.