According to Dan Ariely, an expert on human motivation and behaviour, rationalisation makes it very easy to be dishonest without feeling like you’re doing anything terrible. Moreover, good people doing good work who cheat a little bit do more harm than big cheaters. But, it turns out, reminders about moral codes, even when they’re not your own, result in less cheating, as does the chance to open a new page, such as through confessing or asking forgiveness.