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. Dan Ariely is the James B. Duke Professor of Psychology and Behavioral Economics. He teaches at Duke University and is the founder of The Center for Advanced Hindsight and also the co-founder of BEworks. Ariely's talks on TED have been watched over 7.8 million times. He is the author of Predictably Irrational and The Upside of Irrationality, both of which became New York Times best sellers, as well as The Honest Truth about Dishonesty.