Skip to main content

Verified by Psychology Today

Evolutionary Psychology

When inclusion costs and ostracism pays, ostracism still hurts

When inclusion costs and ostracism pays, ostracism still hurts.


The Savanna Principle

, a fundamental observation of evolutionary psychology, states that the human brain has difficulty comprehending and dealing with entities and situations that did not exist in the ancestral environment. An incredibly ingenious experiment brilliantly illustrates this point.

The Savanna Principle

Humans are a highly social species, and they rely and depend on each other for survival. For this reason, humans have always lived in social groups. Because humans are highly dependent on others in their groups, ostracism – being excluded from their social groups and the benefits they provide – has always been costly throughout human evolutionary history, and their very survival has often depended on being included in their groups.

It is therefore not surprising at all that humans have evolved psychological mechanisms that incline them to seek group affiliation and avoid ostracism. fMRI studies have shown that being ostracized activates the same region of the brain that lights up when individuals experience physical pain. In other words, humans are designed to feel pain when they are ostracized. Given how dangerous being excluded is for human survival and how very costly ostracism is, this makes perfect evolutionary sense.

But what if ostracism was not costly at all? What if, instead, being included is costly and being excluded is beneficial? Would people then come to enjoy being excluded and fear being included? That is the question that motivates Ilja van Beest and Kipling D. Williams to conduct their ingenious experiment in their 2006 paper “When inclusion costs and ostracism pays, ostracism still hurts” published in the Journal of Personality and Social Psychology.

In their experiment, they use a variant of a multi-player computer game called Cyberball. In Cyberball, three players interact virtually and toss a ball back and forth between them on their computer screens. The players never meet each other in person. (The other two players on the screen are in fact simulated actors programmed to behave in certain ways, not other human subjects. But, of course, the human subjects don’t know this during the experiment.) Their experiment has a 2 (gain vs. loss) x 2 (inclusion vs. exclusion) design.

In the gain condition, the subjects earn 50 cents every time a ball is tossed to them and they toss it back to one of the other two players. In the loss condition, the subjects lose 50 cents every time a ball is tossed to them. In the inclusion condition, the subjects are fully included in the three-person group, and receive one-third of the tosses. In the exclusion condition, after the first two tosses, the subjects never receive another toss and simply watch the other two players toss the ball back and forth between each other. van Beest and Williams’s experimental design makes these two factors completely independent of each other. Some subjects gain money while being included, some subjects gain money while being excluded. Other subjects lose money while being included, still others lose money while being excluded. Then, after the Cyberball game is over, the researchers measure the subjects’ satisfaction and mood.

Their statistical analysis shows that the subjects are much more satisfied and happier when they are included than when they are excluded, regardless of whether they are in the gain or loss condition. Even in the loss condition of the experiment, the subjects report being much happier if they are included in the group than if they are excluded. They are happy and satisfied to be included in the group even when being included costs them money!

Throughout the course of human evolution, exclusion was always costly and inclusion was always beneficial. These two things always went together, because there were no experimental psychologists in the ancestral environment to manipulate these variables independently. There were no such things as beneficial exclusion and costly inclusion. The human brain therefore cannot comprehend them. The human brain implicitly and unconsciously assumes that all ostracism is costly, just as it assumes that all sex potentially leads to reproduction (and that’s why we still experience sex with contraception as pleasurable).

Microeconomic theory, or any other theory of human behavior which assumes that human behavior is rational and based on carefully calculated cost-benefit analysis, cannot explain van Beest and Williams’ remarkable findings that humans are happy to lose money and sad to make money. Without the Savanna Principle, it would be difficult to explain why ostracism makes people sad when it pays. This is one of the many reasons why evolutionary psychology is superior to microeconomics as a theory of human behavior (even when we are not talking about sex differences) and why we must kill all the economists.

advertisement
About the Author
Satoshi Kanazawa

Satoshi Kanazawa is an evolutionary psychologist at LSE and the coauthor (with the late Alan S. Miller) of Why Beautiful People Have More Daughters.

More from Satoshi Kanazawa
More from Psychology Today
More from Satoshi Kanazawa
More from Psychology Today