Every now and then, I hear someone say that game theory doesn’t tell us anything we don’t already know. In a sense, they are right—game theory is a methodology, so it’s not really telling us anything that our assumptions are not. However, I challenge someone to tell me that they would have believed most of the things below if we didn’t have formal modeling.

People often take aggressive postures that lead to mutually bad outcomes even though mutual cooperation is mutually preferable. Source.

Even if everyone agrees that an outcome is everyone’s favorite, they might not get that outcome. Source.

Sometimes having fewer options is better than having more options. Source.

On a penalty kick, soccer players might wish to kick more frequently toward their weaker side as their weaker side becomes increasingly inaccurate. Source.

In a duel, both gunslingers should shoot at the same time, even if one is a worse shot and would seem to benefit by walking closer to his target. Source.

There’s a reason why gas stations are on the same corner and politicians adopt very similar platforms. And it’s the same reason. Source.

Closing roads can improve everyone’s commute time. Source.

Fewer witnesses to a crime might be preferable to more. Source.

You should bid how much you value the good at stake in a second price auction. Source.

If you pay the value you think something is worth, you are going to end up with a negative net profit. Source.

Lighting money on fire is often profitable. Source.

Going to college can be valuable even if college doesn’t teach you anything. Source.

An animal might be better off jumping high in the air repeatedly than running away from a predator. Source.

Knowing just slightly more about the value of your car than a potential buyer can make it impossible to sell it. Source.

Nigerian email scammers should say they are from Nigeria even though just about everyone is familiar with the scam. Source.

Everyone might mimic everyone else just because two people chose to do the same thing. Source.

A biased media may be better than an unbiased media. Source.

Every voting system is manipulable. Source.

You might want to abstain from voting even though you strictly prefer one candidate to another. Source.

Unanimous jury rulings are more likely to convict the innocent than simple majority rule if jurors vote intelligently. Source.

The House of Representatives caters to the median member of the majority party, not the median member of the institution overall. Source.

Plurality, first-past-the-post voting leads to two-party systems. Source.

United Nations Security Council members sometimes do not veto resolutions even though they strongly dislike them. Source.

Without the ability to propose offers, you receive very few benefits from bargaining. Source.

Settlements always exist that are mutually preferable to war. Source.

Fighting wars removes the need for war. Source.

You might want to shoot to miss in war. Source.

Nonproliferation agreements can be credible. Source.

Weapons inspections are useful even if they never find anything. Source.

Economic sanctions are useful even though they often fail in application. Source.

Pitchers shouldn’t change their pitch selection with a runner on third base, even though curveballs are more likely to result in wild pitches. Source.

Sports teams can benefit from a lack of player safety in contract negotiations. Source.

You shouldn’t try to maximize your score in Words with Friends/Scrabble. Source.

In speed sailing, competitors deliberately choose paths they believe will be slower. Source.

The first player wins in Connect Four. Checkers ends in a draw. Source.

Chess has a solution, though we don’t know it yet. Source. (Or maybe not.)

Warren Buffett was never going to pay $1 billion the winner of the March Madness bracket challenge. Source.

Park Place is worthless in McDonald’s Monopoly. Source.

Losing pays. Source.

As drug tests become more accurate, they should be implemented less often. Source.

Am I missing anything?