Over the past decade or so, my colleagues and I have taken a close look at why people cheat, using a variety of experiments and looking at a panoply of unique data sets—from insurance claims to employment histories to the treatment records of doctors and dentists. What we have found, in a nutshell: Everybody has the capacity to be dishonest, and almost everybody cheats—just by a little. Except for a few outliers at the top and bottom, the behavior of almost everyone is driven by two opposing motivations. On the one hand, we want to benefit from cheating and get as much money and glory as possible; on the other hand, we want to view ourselves as honest, honorable people. Sadly, it is this kind of small-scale mass cheating, not the high-profile cases, that is most corrosive to society.
Dan Ariely shares some insights on why we cheat: