As humans, we have an innate desire for things to be fair.
If you think back in history, humans have been making things fairer since the dawn of time. Freedom of religion, abolishment of slavery, women’s right to vote, the civil rights movement, and same-sex marriage have all been social movements where humans have fought to make things fairer.
I’m not the only one asking why we need fair, there was a study conducted by Sarah Brosnan with Capuchin Monkeys looking at if human’s aversion to unfair treatment was a result of cultural influences like religion, government, education institutions. The study paired several female monkeys next to each other in cages and trained them to exchange a small granite rock with their human handlers within 60 seconds receiving a reward, in most cases, a piece of cucumber.
Partners of capuchins who made the swap either received the same reward (a cucumber slice), or a better reward (a grape, a more desirable food), for the same amount of work or, in some cases, for performing no work at all.
The response to the unequal treatment was astonishing: Capuchins who witnessed unfair treatment and failed to benefit from it often refused to conduct future exchanges with human researchers, would not eat the cucumbers they received for their labors, and in some cases, hurled food rewards back at the human researchers.
These findings were significant because they confirmed that not only did capuchins expect fair treatment, but that the human desire for equity has an evolutionary basis.