Paul McCartney had a baby when he was 61; Rod Stewart was 66; Rupert Murdoch was a stunning 72. Not only does that mean they'll have less stamina than the average dad, that means they'll, well, check out a lot sooner too.

Operating-room errors hold a special terror for patients, if only because they seem like the most avoidable kind of complications. The occasional horror stories of patients who have the wrong leg removed or the wrong knee replaced generate the most headlines, as do tales of patients whose identities are mixed up entirely.

The vexing thing about human behavior is that when we say we know we should do something, we really and truly do know it. It's hard to be 50 lbs. overweight or smoke a pack a day or feel miserable every moment you spend at work and not understand in a deep and primal way that change is in order - and that in some cases it could even save your life.

Kids whose puberty begins too soon face not just psychological risks, but physical ones too, with an increased likelihood of cancer, as well as skeletal changes that could prevent them from attaining their full adult height.

If you're an older sibling and you have a younger sibling who needs mentoring or is afraid of the dark, you develop nurturing and empathic skills that you wouldn't otherwise have.

Narcissism falls along the axis of what psychologists call personality disorders, one of a group that includes antisocial, dependent, histrionic, avoidant and borderline personalities. But by most measures, narcissism is one of the worst, if only because the narcissists themselves are so clueless.

I grew up in a suburb of Baltimore with an extremely high concentration of Jewish families - where the Levys and Cohens in the high school yearbook went on for pages, where I could count far more temples than I ever could churches. Anti-Semitism, in our cultural biodome, was mostly an abstract concept.