We Are Programmed for Fairness

Even monkeys know when they aren't treated fairly.

Posted Apr 07, 2017

In a TED talk, primatologist Franz de Waal jokes that a philosopher wrote to him that it isn’t possible for monkeys to have a sense of fairness since fairness wasn’t invented until the French Revolution. Why de Waal pokes fun at the philosopher is that de Waal’s work at the Yerkes Center in Atlanta demonstrates beyond a reasonable doubt that a sense of fairness exists in chimps.

In the classic study, available for viewing on Youtube, two monkeys are placed side-by-side in separate plexiglass cages, so they can see one another. The first monkey hands the trainer a rock and receives a cucumber. De Waal points out that monkeys would be happy to perform this task for a long time, content with the cucumber. Now the second monkey hands the trainer a rock and receives a grape. The first monkey gives the trainer a rock and receives a cucumber again. After nibbling it, it throws the cucumber back at the trainer and shakes the cage. Each time scene is repeated, the monkey receiving the cucumber throws it back at the trainer.

De Waal says that what you are watching is the Wall Street protest. It is also some of the recent presidential election results.

No one taught the second monkey that getting a cucumber instead of a grape for performing the same task was unfair. It knew it because fairness is a concept that is hardwired into primates (and probably some other animals as well), as it is with humans.

Fairness comes out of the need for social animals to cooperate. Without cooperation, we would fail. After all, humans don’t run as fast as bears, have hearing as keen as dogs, have night-vision like cats, nor echolocation like bats. We don’t have fangs or claws. We are really pretty pathetic—except for the high degree of sociality, which allows us to work together even with strangers or people we will never know or meet.  

What elevated us to the alpha position amongst animals is our cooperative natures. Because we work together we succeed like no other species. Cooperation is possible because by sharing we come out ahead. What undermines cooperation is cheating—that is, when someone gets what they don’t deserve. Again, a look at primates makes clear the importance of cooperation and the penalty for not. Observations of monkeys in Puerto Rico show that when a troop of monkeys are foraging for food, when one monkey finds a stand of bananas, it alerts the others. Then everyone is fed. Occasionally, there is a monkey that finds bananas and keeps them for himself. If the others discover this, they pummel the cheater.

Cheaters aren’t playing fair. And cheaters are punished, when caught, because they are a threat to the welfare of the community by undermining cooperation.

So when children whine, “It isn’t fair,” it isn’t because someone has taught them about fairness. It is because fairness needs to be paid attention to. The child may be wrong in a particular case about which they are complaining. Knowing what is fair can get complex and difficult. But when one gets a cucumber and the other the grape, even though both performed the same task, that is unfair. Even a monkey knows that.