-People who wear practical shoes tend to be relatively agreeable.

-Calm, collected folks seem to get a kick out of wearing shoes that look uncomfortable (maybe to express the roaring ball of mayhem and agony they're constantly hiding within?).

-Aggressive people tend to wear ankle boots, which seems to have no inherent logic at all ... until you realize that they're clearly subconsciously selecting their footwear for better kicking-stuff-angrily ergonomics.

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"Oh yeah, that's a pair of Class 5 Coccyx Breakers."

If you're reading this and thinking, "Well, my shoes don't say anything deep about my personality, I just picked them because they were comfortable and cheap!" keep in mind that it's a certain personality type who thinks that way. That's the point -- no matter what logic you think you're following in your own head when you step into your local mall's Shoes 'N' Shit store, you're still following logic that makes sense to your personality type. Making that purchase reveals that type to the world.

How It Works

To be clear, we're not talking about how giving somebody a candy bar will put them in a better mood and thus make them more willing to do nice things (although one experiment did find that, it's also kind of obvious). No, they actually did five different studies (the abstract of which hilariously points out that nice people indeed rarely taste sweeter than others, thus gently alluding to another, far darker research project behind this one) and found that a general preference for candy means the person is also more likely to be agreeable and do good deeds, just because. They were just nicer people than the ones who, say, prefer potato chips instead of chocolate at snack time.

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"These chips would go great with burning several men to death in an elevator."

And it gets weirder: Test subjects already knew that this would be the result. The subjects they surveyed anticipated that the candy-loving subjects would be more selfless and agreeable than people who liked savory or salty snacks. The experiment was just confirming what people had already observed in their everyday lives, even though it makes no sense. So maybe the innate goodness that lies in the heart of mankind is actually diabetes.

So if you have a friend or family member with a newborn and you wonder how they're doing, you can either ask them or just see which hand they use to hold the baby. No, really.

How It Works

Dig up some of your baby pictures. Which arm did your mom use to cradle you? Hell, just imagine holding a baby right now -- which arm would you employ? Chances are you'd use the left one. The vast majority of people do, regardless of their dominant hand. It's just one of those weird little bodily hiccups nearly all humans share.

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"Every day, you teach me so many new things ..."

In fact, it's so widespread that when scientists realized that not everyone was doing this, they started digging in ... up until they actually identified it as a potential way to tell if the mother was suffering from depression. Stressed out and depressed mothers actually cradle their babies in their right arm a lot more often than healthy, happy moms. More than twice as often, in fact -- the ratio is 14 percent right-hand bias of the healthy mothers, compared to 32 percent of the depressed ones.

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"... mostly, how to hate."

As for why, the scientists couldn't offer a guess. We're going to speculate that gestures made by stressed or annoyed people, such as the finger or that sarcastic "jerking off" motion, are more easily made with the left hand, so they instinctively need to keep it free. Prove us wrong, science.

Last time, we pointed out that people with wide cheekbones tend to be less trustworthy. That sounds like some unfair stereotype, but it's just a matter of body chemistry -- more testosterone equals a bigger face. And how much testosterone you have goes a long way toward determining your personality type.

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"I'd trade these sick guns for free will any day of the week."

Likewise, the classic image of a beer-guzzling, wedgie-giving jock is pretty much carved in stone: a big, wide-faced dude with a toothy grin and rugged features. Faces like that are familiar from a thousand movies and a million school grounds. They are the guys with the varsity jackets, beer bongs, and stupid bro lingo, banging every chick in school while making you feel like the loser you'd have to wait for years to realize you never actually were. But in certain circumstances, that bully-faced guy is actually guaranteed to be nicer than everyone else ... as long as he perceives he's on your team.

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"I WOULD DIE FOR YOU!"

How It Works

Those guys don't do what they do because they're mindlessly cruel; they do it because they're competitive.

To study this, researchers made male volunteers play a game in groups. Some of the groups were told that their scores would be compared to a rival school, while other groups were just playing for the hell of it. Surprisingly enough, men with classic bully faces were a lot more likely to risk their personal assets for the benefit of their group's overall results ... but only when they were told they were up against a rival school. They were willing to be altruistic as long as they thought it would help them win.

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"I think I can stab two of 'em. They'll arrest me, but we'll still wind up ahead."

Other studies seem to support this. As long as there's a competitive situation of any kind going on, Jock Face Guy has a tendency to be more productive, driven, co-operative, and -- above all -- willing to sacrifice his own well-being for the benefit of the group he views as his own. This applies in even the highest walks of life, by the way -- from CEOs to presidential candidates, that stupid, rugged, wide jock face gives away these men's drive for achievement, and the time and dedication they pour into their close groups of friends and colleagues. All because of how much testosterone they were exposed to in the womb.

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"I take estrogen pills, because I refuse to sit through any Little League games."

If it depresses you to think that so much of people's personal destinies are written before their birth, well, we have more bad news ...