More and more NFL players have been willing their bodies to science so that their brains can be studied even if they die of other causes.

No one ever pretended that shopping for anything is a rational experience. If it were, would there be Fluffernutter? Laceless sneakers? Porkpie hats? Would the Chia Pet even exist?

What people fear most about tragedy is its randomness - a taxi cab jumps the curb and hits a pedestrian, a gun misfires and kills a bystander. Better to have some rational cause and effect between incident and injury. And if cause and effect aren't possible, better that there at least be some reward for all the suffering.

Science has yet to isolate the Godiva Chocolate or Prada gene, but that doesn't mean your weakness for pricey swag isn't woven into your DNA. According to a new study of identical twins, it's less TV ads or Labor Day sales that make you buy the things you do than the tastes and temperaments that are already part of you at birth.

Humans are crude linguists from the moment of birth - and perhaps even in the womb - to the extent at least that we can hear spoken sounds and begin to recognize different combinations of language sounds.

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.

Identical twins are ideal lab specimens for studying the difference between learned and inherited traits since they come from the womb preloaded with matching genetic operating systems. Any meaningful differences in their behaviors or personalities are thus likely to have been acquired, not innate.

Psychopaths know the technical difference between right and wrong - which is one of the reasons their insanity pleas in criminal cases so rarely succeed; they just fail to act on that knowledge.

The golden child may be the oldest one, unless it's the youngest. It may be the toughest one, unless it's the most sensitive. It's not even necessary that Mom and Dad have the same favorite - and typically they don't.

Older siblings get more total-immersion mentoring with their parents before younger siblings come along. As a result, they get an IQ and linguistic advantage because they are the exclusive focus of their parents' attention.

Introverts listen better, they assess risks more carefully, they can be wiser managers. It's not for nothing that the Silicon Valley billionaires are so often the retiring types.

The best you can sometimes do is learn to take a breath, count to ten and simply accept that try as you might, no, your husband will never, ever learn not to drop a wet towel on the bed. That acceptance too counts as resolving a fight.

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 jellyfish is little more than a pulsating bell, a tassel of trailing tentacles and a single digestive opening through which it both eats and excretes - as regrettable an example of economy of design as ever was.

A cockroach likely has no less brainpower than a butterfly, but we're quicker to deny it consciousness because it's a species we dislike.

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.

A mere ape in our world may be a scholar in its own, and the low life of any beast may be a source of deep satisfaction for the beast itself.

As MBA professors endlessly tell their students, companies do best when they stick to what they do well. There's a reason Apple doesn't make blenders. There's a reason Haagen-Dazs doesn't sell meat. And there's a reason drug companies should focus on saving and improving lives - not jeopardizing them.

Well, I think of the folks who are the climate deniers as the flat Earthers and the people who say the moon landings never happened.

Certainly, people can get along without siblings. Single children do, and there are people who have irreparably estranged relationships with their siblings who live full and satisfying lives, but to have siblings and not make the most of that resource is squandering one of the greatest interpersonal resources you'll ever have.

Overspending is as certain a part of the holiday season as overeating. But pushing away from both the table and the cash register at least a little bit sooner can make the post-holiday hangover hurt a little bit less.

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.

Everybody loves to spend money at least some of the time - because everybody loves the stuff you can buy with it. The key to the pleasure level of any transaction is the balance between the pain of the payment and the reward of the purchased object.

Spare a thought for the poor introverts among us. In a world of party animals and glad-handers, they're the ones who stand by the punch bowl. In a world of mixers and pub crawls, they prefer to stay home with a book. Everywhere around them, cell phones ring and e-mails chime and they just want a little quiet.