This blog post explores the reasons why humans choose altruistic actions despite being inherently self-interested beings, and examines the evolutionary causes hidden behind this behavior.
What exactly is an “altruistic act”? Simply put, if my sacrifice or effort allows another person to benefit, it can be considered an altruistic action. For instance, volunteering in disaster zones to aid those in need, donating to someone begging on the street, donating blood to strangers, or donating hair grown over a long period—all these can be considered “altruistic acts.” Such examples are easily found around us with just a little thought. Charitable activities, donation campaigns, blood donations, and similar actions we frequently encounter in daily life are all part of altruistic behavior. They hold significant value precisely because they are undertaken for the public good of society, transcending individual interests.
Altruistic acts function as one of the crucial foundational elements of human society, extending beyond mere actions. Since human society cannot properly function without consideration and cooperation towards others, altruistic behavior plays an essential role in building trust among members and, further, in promoting the stability and development of the community. So, what significance do these altruistic acts hold from the perspective of human instinct and evolutionary theory?
Humans are born with an instinctive tendency to minimize losses and maximize gains. While this instinct provides natural motivation for survival and prosperity, altruistic behavior can be seen as acting against this instinct. For instance, actions that sacrifice one’s own resources to help others may appear, on the surface, to be disadvantageous. So why, then, do altruistic behaviors persistently emerge in human societies? Several hypotheses have been proposed to explain this question, the most prominent being the “Repetition-Reciprocity Hypothesis.” This hypothesis posits that humans are not purely selfish beings, but rather pursue their long-term interests through cooperation and consideration within reciprocal, repeated relationships.
To understand this hypothesis more concretely, consider the story of a village inhabited by people whose arms cannot bend. Because all residents in this village have arms that won’t bend, eating alone is impossible. If each person tried to satisfy only their own hunger, they would never be able to eat without mutual assistance. However, by feeding each other, they can finally fill their stomachs. In this situation, it’s easy to see that cooperation is the only solution. In such circumstances, where helping others ultimately leads to receiving help in return, altruistic behavior naturally occurs. The crucial point here is that altruistic actions are not mere sacrifice but rather an investment in one’s own long-term benefit.
Applying the Reciprocity Hypothesis, the reason altruistic behavior persists in society is to increase the likelihood of receiving rewards later within long-term relationships. For example, with people we frequently meet and interact with, we build mutual trust and form relationships where we help each other when needed. Such social contracts can yield greater long-term benefits even if they involve temporary losses. In other words, altruistic behavior helps maintain relationships with others, thereby creating an environment where one can receive ongoing support.
Then, wouldn’t an increase in altruistic behavior lead to more selfish people also benefiting and proliferating? This is a valid concern. However, according to the Reciprocity Hypothesis, altruistic behavior is not unconditional sacrifice but based on conditional cooperation. That is, altruistic individuals help others because they consider the possibility of receiving similar help in the future. Therefore, a situation where only selfish individuals benefit is actually unsustainable. This is because, within a mutually reciprocal relationship, giving and receiving help yields the greatest long-term benefit.
However, the Reciprocity Hypothesis cannot explain all altruistic behavior. Consider, for example, the story of an elderly man who donated money he had collected through begging his entire life to help struggling students. This man gave away his resources to help others even in a situation where he could expect no reward from that donation. This is an example difficult to explain through the Tit-for-Tat Hypothesis. The grandfather did not form a repeated relationship with the students he helped and could not expect any benefit from it. Such cases represent a pure form of altruistic behavior we cannot explain, revealing the limitations of the Tit-for-Tat Hypothesis.
In conclusion, the Reciprocity Hypothesis is a highly effective theory for explaining social cooperation and altruistic behavior in many cases. This hypothesis demonstrates that humans are not merely profit-seeking beings but can pursue long-term benefits through cooperation and consideration. However, this hypothesis cannot explain every situation and still has limitations when it comes to truly altruistic actions involving pure sacrifice.
