My three-year-old was angry when her friend picked the red cup and she was stuck with the blue cup. Of course I told her that we let our guest choose. But then I wimped out and made sure to have identical cups and identical cupcakes whenever I served children. I appeased my daughter's anger instead of teaching her to manage it.
To children, fairness means getting what another person has. This view doesn't necessarily go away as we mature. It often gets covered up with more sophisticated ways of saying “No fair!” You can claim you are a victim of injustice instead of noticing that you want the red cup when you see someone else enjoying it. If you surround yourself with like-minded people, you can spend your whole life convinced that the world has deprived you instead of learning how your brain works. My children did not benefit from the cocoon of aritifical equality I created for them.
We mammals have a strong urge for the one-up position and an intense fear of the one-down position. You don’t think this consciously, but your brain releases serotonin when you're one up, and cortisol when you're one down. You might blame this on "our society," but monkeys did the same thing 50 million years ago. Seizing the advantage promotes survival in the state of nature, and natural selection built a brain that rewards you with the good feeling of serotonin when you seize the advantage. Watching another get the advantage feels like a survival threat because in the state of nature, it is.
You may insist that you don’t think this way, but you easily see this in others. We don't see it in ourselves because the mammal brain never tells you in words why it is releasing neurochemicals. It just propels you toward behavior that stimulate serotonin and avoids behaviors that stimulate cortisol. And each time these chemicals flow, they pave neural pathways that tell you how to feel good in the future.
But when you get the red cup you desired, the serotonin will be metabolized in a short time. Your brain will look around for ways to get more. You can end up with a lot of cortisol in your quest for serotonin. Maybe you don't see this in yourself. Maybe you hate people who are always questing after something and feel ethically superior to them. See! You did it! Your brain keeps finding a way to put you in the one-up position.
You work hard to manage these mammalian urges, so you get irritated when others seem to indulge them. The problem is that we are not objective judges. Each brain, it feels somehow wrong when others seize the one-up position, but when you do it, it just seems....fair.
Here’s a grown-up example: Imagine you’re at a four-way stop sign and you see another guy rolls through it. “That’s outrageous!" you think. "He could have killed someone. Where are the police? What is wrong with this world!?!” But the next day, you roll through a stop sign. The police happen to be there and you get ticketed. You may think: “Everyone does it! Why should I get punished? What’s wrong with this world?!?!?””
Very few people tell themselves, "Law enforcement protects us. The police can't be there 100% of the time. I volunteered for a ticket when I rolled past the stop sign." People tend to feel wronged when they're in the one-down position, and righteous when they’re in the one-up position.
You have probably been told that monkeys share everything, and inequality is an evil of “our society.” Researchers who conform to the “altruistic monkey” meme get grants and headlines. They are promoting their self-interest in the name of altruism. But they are obviously competing, like other mammals. Even plants compete! You are competing too. Instead of being mad all the time about other people’s competitiveness, you can find peace by accepting the fact that you are a mammal among mammals.
You can learn to enjoy the blue cup when you have it and the red cup when you have it instead of being constantly frustrated about what others have.
For more information on our mammalian impulses:
It's Not Easy Being Mammal is my slide deck full of beautiful animal photos. (You can also download it from my Psychology Today bio page under "Research Papers" in the bottom right corner.)
Many free downloads at my website, Inner Mammal Institute.org.