In this blog post, I will revise and edit an article that examines the justification for altruistic behavior from the perspectives of the free-rider problem and human self-interest, organizing it into a natural and easy-to-read format.

The Free-Rider Problem and the Need for Cooperation

Group projects are a source of stress for most students. This is because they must collaborate with classmates they’ve just met in class to complete a large volume of work. It would be ideal if all group members participated diligently, but in reality, this is rarely the case. It’s easy to find complaints online about students who act as free-riders—those who do nothing until the assignment is finished or cut off contact entirely. Professors are undoubtedly aware that this free-riding problem exists. So why do they assign group projects anyway?
As we move forward in life, we will constantly face tasks that must be solved collaboratively with others, just like group projects. Collaboration is required on various scales—from dividing household responsibilities at home to corporate projects on a larger scale. The purpose of group projects can also be seen as teaching students how to work with others to get things done. However, when free-riders emerge, an excessive burden is concentrated on certain individuals, making it difficult to achieve these educational goals. So, how can we prevent free-riding? Furthermore, why should we help others—even at the cost of sacrificing some of our own interests—rather than free-riding? What is the reason we should live righteously? In this article, I intend to examine this issue not from the perspective of moral coercion, but from the standpoint of what is “desirable and appropriate.”
I believe that to prevent free-riding, members of a community must be able to impose appropriate sanctions on free-riders. First, to prevent free-riding, we must understand its root causes. Only by eliminating these causes can we reduce free-riding itself.
Let’s consider the logic of a free-rider. For example, think of someone who doesn’t pay their apartment maintenance fees. Their mindset is: “Security guards are absolutely necessary. Even if I don’t pay my maintenance fees, others will cover the costs and hire security guards. So I can use the security service without paying.” In other words, they want to use the security service but expect others to bear the cost. To put it another way, free-riding is the act of enjoying public benefits without incurring any personal cost.
So, how can we eliminate this profit structure? The answer can be found in reality: by imposing sanctions. If fines or penalties are imposed on free-riders, free-riding is no longer free—because sanctions create a cost associated with free-riding. Consequently, the individual benefit gained through free-riding is reduced. If the level of sanctions is raised so that the expected benefit of free-riding becomes zero, free-riding will become unlikely to occur. In other words, if members of a group can impose sanctions whenever an individual acts in a way that harms the group’s welfare, that individual will behave in a manner consistent with social welfare to avoid negative consequences.
In a simple group project, there are almost no means to sanction free-riders. Since everyone receives the same grade based on the final group project, it is difficult to impose any real penalty on free-riders unless they voluntarily forfeit their own grade. Furthermore, even if group members attempt to impose sanctions on their own, there is little they can do if the free-rider cuts off communication. The most they can do is vent to close friends or spread rumors, but this has virtually no deterrent effect.
To resolve this, group members must be given appropriate means of enforcement. That is why we propose a peer evaluation system. The group peer evaluation system is a method in which group members evaluate one another, and the results are reflected in their individual grades. Through this, group members can directly influence the grades of free-riders.
However, the group peer evaluation system also has its drawbacks. First, the group evaluation itself may not be fair. Second, it is difficult to protect victims from extreme free-riders who have completely given up on their grades.

Limitations of the Peer Evaluation System and Proposed Improvements

First, let’s examine the fairness of peer evaluation. The peer evaluation system awards bonus or penalty points to individual scores based on the average evaluation of group members. For such sanctions to be legitimate, the evaluation itself must be fair.
However, reality may not always reflect this. First, individuals participating in peer evaluation become evaluators simply because they are members of the same group. Evaluators are not subject to objective verification, nor are they bound by any obligation to evaluate fairly. This is similar to selecting jurors without any vetting. Consequently, if some group members provide unfair evaluations, a significant discrepancy may arise between actual contributions and the evaluation results. Since group assignments typically consist of small teams of 3 to 6 people, the impact of a single person’s evaluation on the overall result is very significant.
Second, a majority opinion is not always legitimate. For example, suppose in a group of four, only one person completed the assignment while the other three did not participate. Under normal circumstances, the one who worked should receive a high evaluation, and the other three should receive low evaluations. However, if the three collude to give each other high scores and give the person who actually did the work a low score, the results are completely reversed. When collusion occurs in this way, the few who participated diligently may end up being the ones who suffer.

The Free-Rider Problem and the Justification for Altruistic Behavior

Now, let’s examine the problem of how difficult it is to remedy the situation when an extreme free-rider emerges. The group peer-evaluation system is a method in which group members evaluate one another after the assignment is completed, and the results are reflected in their grades. In other words, the target of the sanction is the group members’ grades. However, if a group member has no interest whatsoever in their grade, peer evaluation loses its effectiveness as a sanction. Ultimately, since there are no sanctions, free-riders can continue to emerge, and victims cannot receive practical assistance until the group assignment is completed. For this reason, the group peer evaluation system has limitations in that it is difficult to guarantee the fairness of evaluation and to protect victims from extreme free-riders. Therefore, I believe the following elements should be added to the group peer evaluation system to ensure fairness in evaluation and to provide relief for victims.
The first is a self-evaluation form. After group activities conclude, each member should document the role they assumed and the work they performed, and provide brief comments. The professor then reviews both the group evaluation and the self-evaluation forms together to verify that the group evaluation was conducted fairly. Through this process, the professor can determine whether a group member who received a low evaluation is a victim of collusion or was actually a free-rider, and provide appropriate redress. Even if the professor does not directly factor the self-evaluation forms into the final grade, the mere existence of a verification process will provide group members with a psychological incentive to evaluate more fairly.
Second is the group member expulsion system. Since the peer evaluation system uses grades as a disciplinary tool, it is ineffective against free-riders who have given up on their grades. Therefore, alternative disciplinary measures are necessary in such cases. A reporting period is established, allowing group members to report free-riders up to one week before the assignment deadline. The reporting deadline is set early to prevent free-riders from merely pretending to be diligent until the reporting period ends and then disappearing afterward. The one-week period is based on the assessment that this is the minimum time required to complete an individual assignment, though it can be adjusted as needed in actual implementation.
If a free-rider is identified, group members must submit evidence that the student did not participate in group activities and request the professor to expel them from the group. The professor contacts the student to confirm whether they intend to continue participating in group activities. If they express a willingness to participate, the group activities continue as usual. However, if the student refuses to participate or cannot be contacted, they are removed from the group and assigned an individual assignment. The group assignment is then evaluated based on the number of remaining group members. If the remaining members are too few to complete the group assignment, they are also instructed to switch to individual assignments. At this point, it is advisable to set the workload for the individual assignment higher than the portion the student would have handled in the group activity, to discourage students from intentionally opting for individual assignments.
Therefore, introducing a self-evaluation form into the peer evaluation system can encourage group members to evaluate each other fairly and provide relief to students harmed by unfair evaluations. Furthermore, in cases of extreme free-riding, the group expulsion system can be used to protect the victims. I believe this is the most effective method for group activities that reduces free-riding while ensuring no victims are created.
As such, various efforts and systems are needed to sanction free-riding and provide relief to victims. In the process, questions may arise such as, “Rather than becoming a victim, wouldn’t it be better to actively engage in free-riding? Is there really a reason to live righteously?” However, to put it simply, the answer is no. This is because altruistic behavior does not only result in losses but also brings benefits to the individual.
Before discussing this, we first need to clearly define what the question “Is there a reason to live righteously?” actually means. In this article, I will define “living righteously” as engaging in altruistic behavior. Furthermore, I define altruistic behavior as an act of helping others while accepting personal loss. Furthermore, I intend to explain the reason for engaging in altruistic behavior not from the traditional moral perspective of a “must”—that is, an obligation—but from the perspective of a “should”—that is, that it is desirable to do so because it also benefits oneself. For this discussion, it is first necessary to clearly define altruistic behavior from the perspective of benefit.
Altruistic behavior is an action that involves helping others while accepting personal loss. However, the concept of “loss” referred to here is highly abstract. Therefore, I will define it more specifically. I define the direct, short-term, and material harm—that is, quantifiable loss—that one inevitably incurs by performing a certain action as “certain loss.” Furthermore, I will define altruistic behavior as an action that benefits others while accepting such certain loss. Later, I will argue that altruistic behavior should be practiced because it brings various benefits to the individual in addition to the certain loss. This is consistent with the earlier logic that, to prevent free-riding, the benefits of free-riding must be eliminated through sanctions.
This raises two potential questions. First, if an action results in certain losses but ultimately benefits the individual when uncertain benefits are also taken into account, can it still be considered altruistic behavior? However, if altruistic behavior is defined to include psychological satisfaction and indirect benefits, people will evaluate its value differently, which could lead to significant variations in the criteria for altruistic behavior. Conversely, if altruistic behavior is defined solely as actions that result in a loss, it becomes difficult to justify such behavior from the perspective of benefit. Therefore, this paper will not expand on this discussion further and will instead use the definition presented earlier.
Second, the question may arise as to whether the benefits gained in this way can always be considered greater than the definite loss. However, indirect or psychological benefits are inherently difficult to quantify. Therefore, it cannot be argued that such benefits are always greater than the definite loss. However, if altruistic behavior brings about indirect or psychological benefits, and an individual judges those benefits to be of greater value than the loss, that can serve as a sufficient reason to engage in altruistic behavior. This paper does not argue that altruistic behavior is always the best course of action, but rather seeks to explain, at the very least, the “reasons why it is desirable to act in this way.”
Let us now return to the original discussion. Earlier, I argued that altruistic behavior brings benefits to the individual. How, then, are these benefits generated? The answer lies in the fact that altruistic behavior creates various forms of benefits through interactions with others, groups, and one’s own conscience. Let’s examine each case separately.
First, altruistic behavior brings long-term benefits through interactions with others and increases the likelihood of belonging to a group from which one can derive greater benefits in the future. A representative theory explaining the former is the reciprocity hypothesis. The reciprocity hypothesis states that, following the principle of reciprocity, people tend to respond with kindness to those who have shown them kindness and with retaliation to those who have caused them harm, and that these interactions occur repeatedly.
For example, consider a situation where you pay a friend’s bus fare. On the surface, it appears that I paid the fare on my friend’s behalf and the situation is over. At first glance, it may seem as though I have only suffered a loss. However, I will continue to meet this friend in the future, and similar situations could easily recur. At that time, the friend is likely to remember the help received earlier and return the favor. Therefore, from a long-term perspective, I can expect to benefit. In other words, altruistic behavior can be viewed as an investment that, while incurring an immediate cost, enables one to anticipate goodwill from others within recurring interpersonal relationships.
The “birds of a feather flock together” hypothesis and the “costly signaling” theory provide evidence for the latter. First, let’s examine the “birds of a feather flock together” hypothesis. People tend to form relationships with those who share similar values or dispositions. In other words, altruistic people are more likely to associate with other altruistic people, while selfish people are more likely to associate with other selfish people. Therefore, people who act altruistically are also more likely to belong to a group composed of altruistic individuals in the long run.
Next, let’s examine the theory of costly signaling. Gazelles living on the savanna live in herds. However, when they encounter a predator like a lion, some gazelles, instead of fleeing, perform a high leap in place. On the surface, this appears to be an inefficient behavior that merely wastes energy. Yet, lions often attack other individuals rather than those gazelles. This is because the ability to leap high signals strong leg muscles and the capacity to run away quickly. In other words, the gazelle is conveying the message through its behavior: “I am healthy and fast, so it will be difficult for you to catch me.”
Altruistic behavior works in a similar way. Helping others even at one’s own expense sends a signal to those around you that “I am a trustworthy person and someone worth cooperating with.” These signals enhance an individual’s reputation and, as a result, increase opportunities to associate with better people. Belonging to a good group also opens the door to various benefits that can be derived from that group. In this way, altruistic behavior creates future benefits through interactions with others. In other words, altruistic behavior can be viewed as a kind of investment in the future.
Now, let’s examine the relationship between altruistic behavior and the group. Altruistic behavior contributes to the prosperity of the group to which an individual belongs, and the individual, in turn, reaps various benefits from the group’s development. In fact, altruistic groups are more likely to thrive—both internally and externally—than selfish groups. Taking the nation—the largest group—as an example, internal factors include the production of public goods, while external factors include cohesion during times of crisis.
Public goods refer to goods or services that everyone can use collectively. Typical examples include national defense, public safety, fire protection, and roads. In selfish groups, members tend to avoid participating in the production of public goods while seeking only to enjoy their benefits. As a result, public goods are not supplied in sufficient quantities to meet societal needs, ultimately hindering the development of the group as a whole.
Furthermore, in crisis situations, sacrifices by members are often necessary for the group’s survival. However, self-interested groups tend to avoid such sacrifices. This difference in cohesion can ultimately lead to a difference in the group’s competitiveness. Even if two groups appear to have similar capabilities on the surface, the group that avoids cooperation and sacrifice is likely to be at a competitive disadvantage in the long run. Ultimately, self-interested groups reduce the group’s overall chances of survival. Therefore, if an individual wishes to benefit from the group’s prosperity, it is more advantageous to act altruistically.
One might counter, “I don’t want to gain any special benefits from the group. In that case, isn’t it okay not to act altruistically?” However, as long as an individual belongs to a group in any capacity, it is difficult to act purely selfishly. This is because the group imposes sanctions.
As we’ve seen earlier, the cooperation of members is necessary for the group’s survival and development. However, if an individual acts selfishly and harms the group’s interests, other members will impose sanctions on that behavior. This phenomenon can be easily observed in everyday life. For example, it is common to see people around a line stop someone from cutting in line. Even those who have not been directly harmed criticize such behavior, because if the order of the entire group breaks down, it will ultimately harm them as well.
Such sanctions are not limited to individuals. Society imposes sanctions on selfish behavior through norms and laws, and in some cases, may even exclude individuals from the group. Through these sanctions, an individual may suffer disadvantages greater than the benefits gained from selfish behavior. Ultimately, even from the perspective of self-interest, acting altruistically becomes more advantageous than acting selfishly. Therefore, individuals are naturally more likely to act altruistically.
Finally, altruistic behavior interacts with an individual’s conscience, providing psychological benefits. Whether conscience or morality is innate or learned through society has long been a subject of debate. However, what is clear is that most people today possess a conscience and a sense of morality. And this conscience brings a sense of satisfaction and fulfillment to individuals when they engage in altruistic behavior.
In fact, you’ve likely experienced a sense of pride after helping someone in need. In this way, altruistic behavior provides the benefit of psychological satisfaction. Conversely, conscience evokes feelings of guilt in response to selfish behavior. The experience of feeling uneasy deep down when turning away from someone in need is also an example of this mechanism at work. In other words, conscience makes us feel a psychological loss from selfish behavior and allows us to reduce that loss through altruistic behavior. Ultimately, altruistic behavior, through its interaction with conscience, brings about psychological satisfaction and reduces feelings of guilt.
To summarize, altruistic behavior may appear to bring only loss to the individual when viewed from a material, short-term, and direct perspective. However, by interacting with others, the group, and one’s own conscience, altruistic behavior generates long-term, indirect, and psychological benefits. Of course, it cannot be definitively stated that these benefits always outweigh the certain losses. Nevertheless, altruistic behavior can be adequately explained not as a moral “must”—an obligation that one is compelled to fulfill—but rather from the perspective of a “should”—a principle that it is desirable to act altruistically because it can also benefit oneself. As discussed earlier, this does not mean that one must act altruistically in every situation. Nevertheless, the fact that the justification for altruistic behavior can be explained in terms of benefit—going beyond a simple moral obligation—is a very interesting perspective.