What Is "The Prisoner's Dilemma?" Here's The Science Behind The Game Theory Problem — VIDEO

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If you've ever had to make a really tough decision, it's possible someone has referred to it as the "prisoner's dilemma." If you've ever been curious about where that term comes from, PBS Digital Studios' BrainCraft YouTube channel recently released a video on the science behind the prisoner's dilemma that breaks it down really well. It's basically a huge, fascinating paradox that not only messes with your head in terms of logic and rationality, but makes you question your own morals, too. If you've ever studied anything related to sociology, political science, or psychology, it's likely you've covered it a million times in your classes; however, even if you aren't a theory nerd like myself, the prisoner's dilemma is actually a really interesting concept that can you help you better understand your own decision-making process, as well as the processes of those around you.

Let's face it: We spend a lot of time analyzing one another, from the motives behind what people say, to the choices they make, and heck, to the choices we think they're going to make. I had a professor once compare the prisoner's dilemma to a really high-stakes game of Rock, Paper, Scissors, and he's right: You're making your own choices based on what you think someone else might do, but you don't know until you've acted.

I've broken down the basics of the prisoner's dilemma below, but be sure to scroll down to check out the full video, too — if you're into game theory, it's totally worth it.

The Premise


The premise of the prisoner's dilemma is as follows: You and someone else have been arrested for committing a crime and imprisoned in solitary confinement, with no way to communicate with each other. Each prisoner is offered a deal: You can either betray the other person by testifying against them, or you can remain silent. Depending on who chooses to do what, one of three outcomes might occur: If you betray the other person, and the other person remains silent, you'll be released, while the other person will serve three years in prison; if both people betray each other, both will also serve in prison, but for a shorter amount of time (two years each); and if both remain silent, both will serve only one year in prison. With both prisoners being interrogated separately, it becomes a gamble: Is the other person going to give you all of the blame? Will they also offer to shoulder some of it? Or should you just save yourself? The question is whether you should help yourself, help the other person, or help both of you.

Suddenly, it's much trickier to make a rational decision when we're trying to predict what someone else is thinking. Researchers assumed we'd be most interested in protecting ourselves (aka, getting no jail time) but the actual results beg to differ; while we want to protect ourselves, we humans have a really hard time turning our backs on one another, and are more likely to share the blame equally. Fascinating, right?

The Original Experiment


The prisoner's dilemma experiment first became popular as the result of research done by Merrill Flood and Melvin Dresher in the 1950s. Instead of running this experiment on actual prisoners, they used college students. Essentially, it went down like this: College students were told they were both accused of a crime of which they were innocent. If you confessed, you got three years of jail time, and the other person got zero. If you share the blame and both confess to having a part in the crime, you each get one year of jail time. If the other person takes the blame entirely, you get no jail time, and they serve three years. The "rational" choice is to remember that you are innocent, so in the effort of self-preservation, you want to do whatever possible to get zero years of jail time.

The Results

The most common result is that both people agree to share the blame and serve one year in prison. That's right: The majority of people would rather spend a year in prison for a crime they did not commit, than know they were essentially sentencing someone else to three years of prison for a crime they also did not commit. To the original researchers, this is decidedly irrational: It's human nature to want to protect ourselves. Why shoulder any part of the blame to help someone else, when you could help yourself entirely?

The Explanation


Like so much to do with human behavior, this one comes down to the brain. In an updated version of the experiment, participants made decisions while connected to a FMRI machine to monitor brain movement. When people cooperated with one another during the study, scientists saw activation in the areas in the brain linked to reward processing. Researchers theorize that this "reward" process is what ultimately stops people from acting with "self-preservation" in mind (aka saving themselves only) and what makes us more likely to cooperate with one another. So, our brains basically reward us for caring about one another. Pretty cool, right?

You can check out the full video here, thanks to BrainCraft.

BrainCraft on YouTube

Images: Jordan Lye/Moment/Getty Images; BrainCraft/YouTube (3)