Interestingly, when smart people feel less alienated, they seem to buy different sorts of books. Instead of condemning American society for not honoring the author’s personality or tastes, the new bestsellers explore the mysteries of human behavior. Think of Malcolm Gladwell’s various books or Daniel Kahneman’s “Thinking, Fast and Slow.” Perhaps once you accept that people really are different — that nobody’s normal and, at least when it comes to food or entertainment or vacations, there’s no one best way to live — you can, paradoxically enough, start to think about the commonalities known as human nature.