A 2010 study in the journal Social Psychological and Personality Science found that the percentage of college students exhibiting narcissistic personality traits, based on their scores on the Narcissistic Personality Inventory, a widely used diagnostic test, has increased by more than half since the early 1980s, to 30 percent. In their book “Narcissism Epidemic,” the psychology professors Jean M. Twenge and W. Keith Campbell show that narcissism has increased as quickly as obesity has since the 1980s. Even our egos are getting fat.
It has even infected our political debate. Donald Trump? “Remarkably narcissistic,” the developmental psychologist Howard Gardner told Vanity Fair magazine. I can’t say whether Mr. Trump is or isn’t a narcissist. But I do dispute the assertion that if he is, it is somehow remarkable.
This is a costly problem. While full-blown narcissists often report high levels of personal satisfaction, they create havoc and misery around them. There is overwhelming evidence linking narcissism with lower honesty and raised aggression. It’s notable for Valentine’s Day that narcissists struggle to stay committed to romantic partners, in no small part because they consider themselves superior.