My latest column in the New York Times:

AS a historian, I’ve spent much of my career warning people about the dangers of nostalgia. But as a mother, watching my son graduate from medical school on Thursday, I have been awash in nostalgia all week.

In personal life, the warm glow of nostalgia amplifies good memories and minimizes bad ones about experiences and relationships, encouraging us to revisit and renew our ties with friends and family. It always involves a little harmless self-deception, like forgetting the pain of childbirth.

In society at large, however, nostalgia can distort our understanding of the world in dangerous ways, making us needlessly negative about our current situation.

Nineteenth-century Americans were extremely worried, the historian Susan Matt points out, about the incidence of nostalgia, which was the term used to describe homesickness in those days. According to physicians of the era, acute nostalgia led to “mental dejection,” “cerebral derangement” and sometimes even death. The only known cure was for the afflicted individual to go home, and if that wasn’t possible, the sufferer was seriously out of luck....

Read the rest here.