"I know I will not make old bones," says Achilles in Christopher Logue's modern Iliad. I personally have seen enough old people staring, drooling, groaning and pissing into their giant diapers to sympathize with a wish to quit while you're still ahead. Today, though, we're all supposed to want to live forever. It's not enough to be sad about Amy Winehouse's death at 27 this week. We're expected to feel something like outrage, because no one is supposed to die that young.

Other eras had a different view. In Book Nine of the Iliad Achilles recounts how his immortal mother had given him a choice. He could have a long, tranquil life at the end of which he would, like most of us, be utterly forgotten—or a life of triumph and glory, which would leave his name shining brightly for thousands of years. But that life would be short. As you're reading about him 3,000 years later, you know what he decided.

Which is hard to get the modern head around. With our technologies for life extension we think it normal to live past 65, 75, or even 85. This is one reason many nations are on the long-term road to insolvency: when the U.S. Social Security program was instituted in 1935, only half of men who lived to 21 could expect to make it to the retirement age of 65. Now nearly everyone makes it, which is threatening to bankrupt future generations.

Why do we think longevity so natural and right? In part, I think, it's because we think of it as the byproduct of living well: We like to think the traits that make life sweet are those that make it long. But this long-term study of longevity over decades suggests that's not so. Over 20 years, Howard S. Friedman, a psychologist at the University of California, Riverside, and his colleagues studied 1,500 "gifted" children identified in 1921 by Louis Terman, a psychologist at Stanford. Friedman's team looked at the lifetime data on these kids, who were about ten when first identified—their relationships, their personalities (as reported by teachers and parents) educations, work history and so on.

Of course, some of the kids in the study were more cheerful and optimistic than others. Some had better sense of humor. On average, they died sooner. Similarly, people who seemed happy-go-lucky and didn't stress about work also died at younger ages. And people who reported they felt loved and cared for? Also less likely to life longer. Friedman et al. believe the sunnier people were too cheerful for the long haul—expecting things to work out, they took too many risks.

Who did that leave to win the longevity sweepstakes? As the Publisher's Weekly review put it, "If there's a secret to old age, the authors find, it's living conscientiously and bringing forethought, planning, and perseverance to one's professional and personal life."