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October 18, 2005

Cooperation and Self-Interest as Evolutionary Issues

More evidence that cooperative behavior enhances a group's chance of survival in evolution.

In economics, arguments about the power of self-interest vs. cooperation are often based on moral grounds. Polemicists cite the role of each in contributing to the common good, or to a person’s moral character, and so forth. But from an evolutionary perspective, the question is quite different: Does a given attribute represent an “evolutionary stable strategy” – i.e., does it contribute to a species’ evolutionary “fitness” in a stable, persistent way over time? Does it enhance a group’s survivability?

By this measure, science is showing that cooperative behaviors have been important features of our evolutionary success. Recent behavioral studies, evolutionary game theory simulations, and cross cultural studies have shown that when there are “free riders” – people who act in their own self interest at the expense of the group – the overall outcomes or fitness benefits for the group are reduced because its members are less willing to reciprocate acts of cooperation. However, when free riders are punished or ostracized, then the cooperative behaviors are returned and sustained.

Hence, free riders are not punished or purged as a result of arbitrary moral arguments or beliefs, but out of very sensible and rational considerations for preserving the overall welfare of all members of the group. The ability of a small group to appropriate for themselves the benefits created by the cooperative efforts of all the members, ultimately jeopardizes those benefits for the entire group.

Given the importance of “fairness” and the dangers of free riders to a group’s survival, it is not surprising that a specific region of the brain has evolved that is dedicated to detecting cheaters. Innate personality traits have also evolved to detect and punish cheaters in social networks. The evolutionary justification for reciprocal behaviors is that they distribute risk. It is in one’s own self interest to attend to the interests of others – even those who are not kinsmen. In the case of some hunting and gathering cultures, the likelihood of a hunter bringing back a large bounty of protein is no more than 4 percent. This gives hunters a keen interest in reciprocating acts of sharing. It diversifies their risks – and increases their ability to survive.

This conclusion of a growing number of evolutionary scientists is anathema to the Chicago School of classical economics, however. It is also rejected by a band of traditional evolutionary biologists who contend that individual self-interest is the primary motivator of human activity. For them, it is a “Central Dogma” that everything revolves around self-interest – the “selfish gene” and the individual, and it is individual selection – not group selection – that is the principal agent of Natural Selection.

Both these points of view, however, are becoming progressively less tenable. As Dan Kahan, a professor at Yale Law School, argues:

The main – indeed only – selling point for the neo-classical theory of collective action is its assertion of behavioral realism. Individuals, it tells us, are inherently self-seeking. Accordingly, we can’t count on them voluntarily to subordinate material interests to the good of society; rather we must alternatively bribe and threaten them through a costly regulatory process….
It turns out, however, the conventional theory isn’t right. Individuals in collective action setting might not act like saints, but they don’t behave like fiends either. They can be counted on to contribute to collective good, the emerging literature on strong reciprocity shows, so long as they perceive that others are inclined to do the same. Bribes and threats are not nearly so necessary as the conventional theory would have us believe; the law can instead enlist our cooperation by furnishing us with ground to trust one another to contribute our fair share to society’s needs.

By assuming that the only tenable means of promoting cooperation is through coercion and the lure of self interest, many of today’s political and economic “realists” are subverting the very conditions for social stabilization that they say they are trying to encourage.

Consider the highly charged example of suicide terrorists. In the vast majority of cases, terrorists have no “self-interested” rationale in becoming international outlaws. They tend to be well-educated and financially well off, and yet are willing to sacrifice their lives for people they don’t know. In terms of evolutionary science, the best explanation for their actions is not the social emotions of self-interest – but of “strong reciprocity.” They are aggressively defending their group. Under evolutionary logic, it is the Americans, the Westerners, who are the self-interested de-stabilizers, the free riders; the terrorists are “martyrs” trying to create fair, cooperative conditions, as their culture understands them.

It is important to bear in mind that there are strong neurotransmitter rewards – chemical inducements – for altruistic and cooperative behaviors, which in a strict neurological sense are equivalent in power to the addictions of sex and drugs. From the vantage point of theories of self-interest, it may seem far-fetched to assert that certain social emotions – affinity, identity, esteem, and cultural standing – can be bound to acts of faceless violence and self destruction. But from the model of reciprocity and punishment, the need to purge free riders – or in this case, infidels – may be a plausible evolutionary explanation.

In cultures of honor – which many Arab cultures are – there is a moral imperative to correct a slight. To right an insult or wrong is morally absolute and binding. It is arguably something that young men are wired by evolution to do. In neurological terms, such acts of sacrifice may be a way the uncertainty of youth is resolved by the certitude of a heroic, socially sanctioned recognition.

It is not surprising that the United States Government is blind to the motivations of suicide terrorists and labels them as “evil.” The Government is itself so committed to perpetuating its own theology of self-interest and materialism that it cannot gauge its alienating impact upon others. The uncanny paradox is that the U.S. Government has adopted the very policies that exacerbate the conditions it is trying to eradicate.