In 2003, the Princeton psychologist Alexander Todorov began to suspect that, except for those people who have hard-core political beliefs, the reasons we vote for particular candidates could have less to do with politics and more to do with basic cognitive processes—in particular, perception. When people are asked about their ideal leader, one of the single most important characteristics that they say they look for is competence—how qualified and capable a candidate is. Todorov wondered whether that judgment was made on the basis of intuitive responses to basic facial features rather than on any deep, rational calculus. It would make sense: in the past, extensive research has shown just how quickly we form impressions of people’s character traits, even before we’ve had a conversation with them. That impression then colors whatever else we learn about them, from their hobbies to, presumably, their political abilities. In other words, when we think that we are making rational political judgments, we could be, in fact, judging someone at least partly based on a fleeting impression of his or her face.