In this blog post, we’ll examine the meaning and limitations of the “Repeated Reciprocity Hypothesis”—a leading theory explaining human altruism—through various examples.
From vampire bats that feed on each other’s blood to humans who help neighbors in distress during disasters, altruistic behavior is observed in many animals. However, human altruism exhibits a truly unique characteristic. The question “Why do we engage in altruistic behavior?” has long been a major research topic in both the social and natural sciences. In ‘The Emergence of the Altruistic Human’ (Choi Jeong-gyu), the author introduces seven hypotheses explaining human altruism based on evolutionary game theory, a field he has studied extensively. Among these, I would like to explain the “Repeated Reciprocity Hypothesis”—the most intuitive and easily understood hypothesis—using a few examples.
The repeated reciprocity (mutuality) hypothesis consists of two core concepts. First, “reciprocity” means “the exchange of specific benefits between parties,” with the key emphasis on the reciprocal relationship. The repeated reciprocity hypothesis explains that altruism arises from this process of exchanging mutual benefits. Simply put, it is the result of acting according to the principles of “an eye for an eye, a tooth for a tooth” and “giving back as much as one has received.” The term “repeated” is added here because the act of giving back in kind presupposes sustained interaction. If the interaction were to end after just one instance, there would be no way to respond or retaliate even if one party simply received the benefit and left; therefore, it would be difficult to explain altruism based on this hypothesis alone.
Let’s look at an example. When I was a senior in high school, a close friend of mine stumbled on the stairs and severely injured his ankle. As it happened, our classroom was on the fourth floor, and since the school didn’t have an elevator, my friend faced significant difficulties commuting to and from school, as well as going to the cafeteria for lunch and dinner. Eventually, another friend and I began helping my injured friend go up and down the stairs, picking up their meals for them, and carrying their bag. Although we were busy preparing for college entrance exams during our senior year of high school, the act of supporting my injured friend can be considered altruistic. This behavior can be explained by the repetition-reciprocity hypothesis. According to this hypothesis, by helping my friend, I come to expect that I will receive some form of help from him in the future. Since there is a possibility that we will continue to keep in touch and interact at least until we graduate from high school—or even beyond—I could respond by ceasing to cooperate with him if he fails to help me later on. In other words, altruism is formed through a process of exchanging benefits based on the premise of repeated interactions.
Consider the following scenario. We often see people giving up their seats on subways or buses to the elderly, pregnant women, or people with physical disabilities. However, in these cases, the likelihood of repeated interaction between the parties is very low, and even if one were to find oneself in a similar situation in the future and not receive a seat, it would be difficult to know whom to retaliate against. The repeated reciprocity hypothesis thus has the limitation of failing to adequately explain cooperative behavior that occurs in situations where repeated interactions are not a given.
So far, we have examined what the “repeated reciprocity hypothesis” is and how the concepts of “repetition” and “reciprocity” are used, using examples. This hypothesis also has the limitation of failing to explain altruism that occurs in situations where repeated interactions are not a given. Nevertheless, the Repeated Reciprocity Hypothesis is a highly compelling theory because it can be easily applied to various real-life examples around us without requiring a deep understanding of complex scientific background knowledge, and it is intuitively easy to grasp.
There is still no single theory that perfectly explains human altruism. Therefore, various hypotheses complement each other’s limitations to explain human altruism. Rather than simply reading this article, it would be helpful to explore what other hypotheses exist besides the repetition-reciprocity hypothesis and to examine the strengths and limitations of each, as this will contribute to a broader understanding of human altruism.
