“According to an apocryphal exchange between F. Scott Fitzgerald and Ernest Hemingway, the only difference between the rich and the rest of us is that they have more money. But is that the only difference? We didn’t used to think so. We used to think that having vast sums of money was bad and in particular bad for you — that it harmed your character, warping your behavior and corrupting your soul. We thought the rich were different, and different for the worse. Today, however, we seem less confident of this.”