Leonard Mlodinow, writing in the New York Times Sunday Review:
We’re all worldly enough to understand that looks matter. You probably know about the famous 1960 presidential debate between an unshaven and tired Richard Nixon and a tanned and rested John F. Kennedy: those who watched on television generally thought Kennedy won the debate, while those who listened over the radio overwhelmingly favored Nixon. Still, even the most jaded politico assumes that appearance is a relatively small factor — and one that we are basically aware of. Everyone knew that part of Kennedy’s appeal was how he looked.
But recent research suggests that we may need to adopt a more cynical attitude.