Toxins love to get you while you're young. Lead, mercury, secondhand smoke and sundry other environmental nasties do a lot more damage when tissue is immature, vulnerable and growing than when it's mature and comparatively fixed.

A close family member once offered his opinion that I exhibit the phone manners of a goat, then promptly withdrew the charge - out of fairness to goats.

What makes spinal-cord injuries as devastating as they are is that everything about them plays out in absolutes: they are instantaneous, utterly disabling and horribly permanent.

Members of royal families are born into a world of indulgence and entitlement, and the princelings who grow up that way may never have to develop the emotional musculature that will allow them to show self-restraint.

There are a lot of ways to make people not like you, but one of the most powerful - if least fair - is to be really, really successful. Nobody resents the guy who just lost his job. But the guy whose Internet start-up made him a billionaire at 25? That's a whole different kettle of envy.

Indeed, the best way to think of willpower is not as some shapeless behavioral trait but as a sort of psychic muscle, one that can atrophy or grow stronger depending on how it's used.

The mind of the polyglot is a very particular thing, and scientists are only beginning to look closely at how acquiring a second language influences learning, behavior and the very structure of the brain itself.