My wife and I both have grandmothers who have lived past 100. Talking with them and their friends, I detect a trend that seems almost universal in the reminiscences of older people: They recall difficult times with a touch of nostalgia. The elderly swap stories about World War II and the Great Depression; they speak fondly of hardships such as blizzards, the childhood outhouse, and the time in college when they ate canned soup and stale bread 3 weeks in a row.