Level 2: Prisoner's Dilemma - Why We Sometimes Betray the People We Should Trust
Imagine this: you and a friend are caught doing something you probably shouldn’t have been doing (we’ll assume it’s mildly illegal, for story purposes). The police separate you in different rooms. They make each of you the same offer:
If you both stay silent, you each get a light fine.
If you betray your friend and they stay silent, you go free and they get a big penalty.
If they betray you and you stay silent, they go free and you get the big penalty.
If you both betray each other, you both get a medium penalty.
You can’t talk to each other. You have to decide whether to trust them and keep quiet or to blame them.
This is the classic Prisoner’s Dilemma, one of the most famous games in game theory.
We can lay out this situation in a table called a payoff matrix. It shows each player’s choices and what they’d get depending on the combination of decisions. Here’s a simplified version for the Prisoner’s Dilemma:
The numbers here are “costs”. The less negative they are, the better. The first number in each cell is your outcome and the second number is your friend’s. For example, in the top-left cell, you both stay quiet, and each get -1 (a small fine). Whereas in the bottom-right cell, you both confess and each get -5 (moderate penalty).
This setup shows how two completely rational people might still choose to betray each other even though cooperating would make them both better off.
Why? Because in the moment, betrayal is safer. No matter what the other person does, confessing guarantees you won’t get the worst possible outcome (-10). But in protecting yourself, you also make sure that both of you land on something worse than the best possible scenario.
The Prisoner’s Dilemma doesn’t just happen in crime dramas. In business, two companies might cut prices to steal customers from each other, even though they’d both make more profit if they kept prices stable. In relationships, people might hold back emotionally if they’re worried the other person won’t reciprocate. In politics, parties may refuse to compromise because they fear the other side will use cooperation as a weapon.
So, how do smart players escape the trap? One way is to play the game more than once. In repeated interactions (whether that’s with a business partner, a friend, or a neighbor), you have a chance to build a reputation. If you cooperate and they do too, trust grows. If someone betrays you, you can respond in kind next time. Over time, this “tit for tat” approach often leads to cooperation because both sides learn that betrayal hurts in the long run.
Next time you feel the urge to take the “safe” option, whether it’s jumping ahead in line or dodging a shared responsibility, pause for a moment. Ask yourself will this choice help me win just this round, or will it help me win the game in the long run? Because in the real world, the game doesn’t end after one round and your reputation is part of the scoreboard.
