Helping Behavior is Non-Zero-Sum

by Michael Ent


In the television show Man vs. Wild, Bear Grylls would venture into inhospitable areas attempting to show viewers how one could survive alone in the wilderness. Few people would be enthusiastic about following in his footsteps. This reluctance is partly because humans generally rely on help from others to fulfill even basic survival needs like food and shelter. Despite extensive training, even Grylls frequently ended up scrounging for insects and drinking his own urine out of desperation.

While studying a group of modern hunter-gatherers, Lawrence Sugiyama found that a majority of adults had suffered an injury or illness that hindered their foraging ability to the point that they would have likely starved if they had not received help from others. In such a group, it often pays to help others in need because you might need to rely those same people in the future if you find yourself in dire straits. In a less relatable example of helping behavior, vampire bats that have just eaten have been found to regurgitate blood to feed hungry bats with whom they have established a reciprocal relationship. When one bat finds food and her friend doesn’t, she may share some of the spoils; when she is starving and her friend finds food, her friend may repay the favor. Importantly, for this type of reciprocal helping behavior to evolve, the benefit to the recipient must outweigh the cost to the helper – it wouldn’t do much good for a satiated bat to regurgitate blood into the mouth of another satiated bat. In other words, for reciprocal exchange relationships to be mutually beneficial, individual helping acts must be non-zero-sum—one party’s gain does not correspond to equal losses incurred by the other party.

In our research, my co-authors and I found that, when people reflected on helping episodes from their past, they reported that the benefits to the recipients vastly outweighed the costs to the helpers. In other words, the help was non-zero-sum. In this research, pairs of friends recalled and reported about occurrences in which they helped each other. This yielded two accounts of each helping episode: one from the perspective of the helper and one from the perspective of the recipient. Both helpers and recipients consistently, and to an equal degree, reported that the benefits of the help outweighed the costs. If people tend to help one another when they can confer large benefits to their relationship partners without incurring much cost, then acts of helping don’t merely transfer value from one person to another, they create gains through exchange.


“If people tend to help one another when they can confer large benefits to their relationship partners without incurring much cost, then acts of helping don’t merely transfer value from one person to another, they create gains through exchange.”


This research relied on subjective reports of costs and benefits, so there could be motivational factors that reduce people’s tendency to report help as non-zero-sum. People tend to report events in ways that cast themselves in an unrealistically favorable light, known as self-enhancement bias. By exaggerating the costs of the help they provided, helpers could cast themselves as self-sacrificing heroes. On the other side of the coin, by downplaying the benefits of the help they received, recipients could highlight their own self-reliance. Both of these distortions could reduce the degree to which people would regard helping acts as non-zero-sum. Nevertheless, we found that both helpers and recipients consistently reported that the benefits of help outweighed the costs.

In our research, helpers and recipients differed on one important dimension: their perceptions of indebtedness. Helpers underestimated the degree to which recipients felt indebted as a result of the help they received. This finding dovetails with previous research that suggests that recipients tend to view the help they receive as more generous than those who provided the help. This type of helper-recipient asymmetry could enable relationships strengthen over time. For example, if I do a favor for my friend, I might view it as trivial and undeserving of reciprocity. However, my friend might view it as a big deal and repay the favor. In this case, I would feel like I received excessive reciprocity and would be motivated to do something nice for my friend in the future. In this way, the helper-recipient asymmetry we found in our research could contribute to self-reinforcing cycles of altruism. Previous research on the victim-perpetrator “magnitude gap” has found a similar pattern at play in escalating cycles of revenge. Victims tend to view transgressions as more heinous than perpetrators. Because of this asymmetry, when victims seek revenge, they tend to do so in a way that seems excessive to the original perpetrators (who may feel that they now have a score to settle)5. Taken together, helper-recipient and victim-perpetrator asymmetries may lead acts of altruism and acts of harm to escalate over repeated interactions of the parties involved. In other words, both altruistic and antagonistic relationships may amplify over time.


“Although helping behavior is not unique to humans, it is a vital part of human nature.”


In a now famous exchange, the anthropologist Margaret Mead was asked what she considered to be the first sign of civilization. Instead of citing tools, religious artifacts, or the like, she cited a healed human femur that was about 15,000 years old. She explained that a broken femur would have been tantamount to a death sentence, and the fact that it had healed indicated that the person must have received help from others. Although helping behavior is not unique to humans, it is a vital part of human nature. The non-zero-sum nature of human helping behavior means that acts of help don’t merely redistribute value, they bring more goodness into the world.



Read the paper: Helping behavior is non-zero-sum: Helper and recipient autobiographical accounts of help