What if I told you that Batman is not the true hero in the Dark Knight saga? What if I told you instead that if The Joker did not exist, Gotham would be overrun by organized crime families and the corrupt politicians that live in their pockets? And what if I told you that there is mathematical proof of this argument's validity? Curious? Read on.
In a recent article in the Journal of Theoretical Biology, two mathematicians and a physicist use a mathematical model show how the "destructive agents" (which they aptly call "Jokers") can help people avoid the tragedy of the commons. What's the tragedy of the the commons? It's when people try to make the world a better place, but doing so is costly. Free-riders can enjoy the benefits of a better world without paying the costs of helping to create it. So free-riders out-compete everyone else, and all are the worse for it.