In this blog post, we explore how altruism is formed in human society based on the theory of group selection and why groups can be more altruistic than individuals.
Why do we behave altruistically? How does human altruism differ from animal altruism? In biology, altruistic behavior refers to an individual helping another individual at the expense of their own resources (energy, food, etc.). It is easy to think that behaviors that waste one’s own resources for the sake of others would disappear due to natural selection, but in fact, altruistic behavior is common in both animals and humans. There are many hypotheses to explain this unusual behavior, and among them, the group selection hypothesis is particularly applicable to humans. In this article, we will examine the influence of altruism in human society.
Looking at human history and culture, we can see that altruistic behavior has been the foundation of society. Early humans formed communities through cooperation and division of labor in order to survive, and this cooperative behavior naturally promoted altruistic behavior. For example, sharing resources obtained through hunting and gathering increased the chances of survival for the entire group. Altruistic behavior strengthened social bonds and promoted trust and cooperation within the group. Therefore, altruistic behavior became an essential element for the survival and prosperity of the group, rather than simply a personal good will.
First, group selection is the process by which a trait spreads throughout society when a group with that trait has an advantage over a group without that trait. Conversely, individual selection refers to the process by which a trait spreads when individuals with that trait have an advantage over individuals without it. In the natural environment, this process usually occurs through genetic means, whereby individuals with advantageous traits reproduce more often, but in human society, it also occurs through cultural means, whereby individuals without advantageous traits imitate the successful strategies of individuals with advantageous traits.
Before we get into a full explanation, let’s think about “raids” in RPG games. Raids are large monster hunts that require dozens of people to work together to defeat monsters that drop much better items than normal monsters. If you were one of the people participating in a raid to defeat a very powerful monster, what would be the simplest strategy to survive the hunt? It would be to participate passively in the hunt without being noticed by others. If you focus on running away while others are busy attacking the monster and getting attacked, your chances of dying will be lower, and you will receive an equal share of the spoils for participating in the raid. From an individual perspective, selfish people have an advantage, so individual choices tend to be selfish. However, from the guild’s perspective, the more people who actively participate in raids, the higher the probability of success. In other words, group selection tends to favor altruistic traits.
As shown above, individual choice and group choice work in opposite directions when it comes to altruism. The reason why it is difficult to use group choice to explain altruism in animals is that individual choice generally has a stronger influence than group choice. However, in human society, there are regulations that slow down individual choice and strengthen group choice, so group choice can be applied.
One of the systems that slows down individual selection is the equal income distribution system. Let’s consider the raid example again. You are participating in a raid with dedication, but you notice that one person is doing nothing but running away. At first, you feel angry, but then you think that maybe you should act selfishly like that person. When you calculate the actual gains of that person, it seems that the effort required to run around and avoid attacks is similar to the effort required to participate actively, and at best, they will only save the cost of one or two health potions. Therefore, you will not try to follow their selfish strategy and will continue to participate actively for the success of the group’s hunt.
In this way, the smaller the gain from selfish behavior, the smaller the power of individual choice. When the gap between individuals is reduced through equal income distribution, the likelihood of adopting selfish strategies with small differences in rewards decreases, and the pressure of individual choice decreases. Various hunter-gatherer tribes still existing in remote areas around the world maintain a strong egalitarian income distribution system based on the communal ownership of resources. Therefore, we can speculate that until about 10,000 years ago, when most of humanity depended on hunting and gathering, communal ownership of resources was the norm, and group selection was stronger than individual selection.
Another reason why group selection is strong in human society is “conformist cultural transmission.” Simply put, conformist cultural transmission is a process in which the higher the proportion of altruistic people, the slower the spread of selfish strategies, and the higher the proportion of selfish people, the faster the spread of selfish strategies. For example, if 60% of people are altruistic, it is easy to think that when choosing people to learn altruism or selfishness at random, the probability of choosing selfish people is 40%, but in reality, the probability of choosing selfish people is much smaller than 40%. The reason for this phenomenon is that when altruistic people are in the majority, they try to spread altruism through the media and school education, and the influence of altruistic people on society becomes greater. To use the raid analogy again, in the process of encouraging and persuading each other to participate before the hunt, most members will be influenced. However, even if there is only one selfish person, most members will not even be aware of their existence, so they will have little influence on the group.
The effects of conformist cultural transmission on group selection are as follows. If conformist cultural transmission works, selfish groups will make individual choices faster, and altruistic members will disappear very quickly, leaving most members with selfish tendencies. On the other hand, altruistic groups will slow down the speed of individual selection, slowing down the disappearance of altruistic members. Eventually, the gap in the proportion of altruistic members between the two groups will widen, and the influence of group selection will also increase.
So far, we have looked at the influence of group selection and individual selection on the spread of altruism and the two underlying factors that amplify the effect of group selection in human society. Let us return to the question we asked at the beginning. How do altruistic behaviors in animals differ from those in humans? Humans have always lived in groups, such as tribes and villages, and due to the characteristics of these groups, they exhibit a tendency toward group selection that is rarely seen in animals, and have evolved in an altruistic direction that benefits the group as a whole.
