The Desire for War

Of the desires on my list of 20 natural desires, none is more controversial than the desire for war. On page 31 of Darwinian Conservatism, I write: "Human beings generally desire war when they think it will advance their group in conflicts with other groups. Human beings divide themselves into ethnic and territorial groups, and they tend to cooperate more with those people who belong to their own group than with those outside their group. So when the competition between communities becomes severe, violent conflict is likely. Human beings desire war when fear, interest, or honor move them to fight for their community against opposing communities. War shows the best and the worst of human nature. War manifests the brutal cruelty of human beings in fighting those they regard as enemies. Yet war also manifests the moral sociality of human beings in fighting courageously for their group. One of the prime causes for the emergence of large, bureaucratic states is the need for increasing military power. War is an instrument of politics, and like political rule generally, warfare is a predominantly male activity."

In Chapter 5 of The Descent of Man, Darwin saw warfare as a crucial factor in the evolution of "the social and moral faculties" through "natural selection, aided by inherited habit." "When two tribes of primeval man, living in the same country, came into competition, if the one tribe included (other circumstances being equal) a greater number of courageous, sympathetic, and faithful members, who were always ready to warn each other of danager, to aid and defend each other, this tribe would without doubt succeed best and conquer the other."

In recent years, a small but growing number of political scientists have applied this Darwinian view to explain war and international relations. This can be seen in three recent books: Bradley Thayer's Darwin and International Relations (2004), Stephen Rosen's War and Human Nature (2005), and Dominic Johnson's Overconfidence and War (2004).

War poses special puzzles for political scientists who employ "rational choice theory," which views human beings as rational maximizers of their self-interest. If human beings are rational egoists, it is hard to see why they would fight wars, because it would seem that rational egoists would negotiate a peaceful resolution of conflicts based on a rational assessment of comparative power, so that the weaker side would yield to the stronger. But instead, nations often show an irrational confidence in going to war and suffering losses that could have been avoided by a rational calculation of interests. It is also hard to see why rational egoists would risk their lives in warfare. Dying in war would seem to be the ultimate sacrifice of one's self-interest to others.

War might also be a puzzle for the Darwinian. After all, why would natural selection favor courage in war if this means that the dead soldier gives up his reproductive fitness?

The writing of some Darwinian political scientists explores these puzzles in ways that confirm Darwin's view of war as a factor in the social and moral evolution of the human species.

In a recent article, Dominic Johnson reports that some wargame experiments show that males show an overconfidence that inclines them to launch unprovoked attacks. Some Darwinian theorists have argued that a disposition to "positive illusions" might have been favored by the evolutionary history of human beings, particularly males. In any case, as Stephen Rosen has argued, a Darwinian view of human nature suggests that human beings are moved not just by a rational calculation of interests but also by emotional impulses inclining them to risky behavior.

In an unpublished paper, Johnson has shown that computer simulations of human evolution suggest that the disposition to heroic sacrifices in war would have been favored by group selection working through genetic evolution, cultural evolution, or gene-culture coevolution. Under certain conditions of competition for scarce resources, groups with courageous members would prevail over other groups with less courageous members. This seems to be exactly what Darwin suggested in his account of the evolution of war "through natural selection, aided by inherited habit."

This also indicates how our moral dispositions--courage, sympathy, cooperation for the good of society--might have been shaped by competition in war. We evolved to cooperate with people in our group in order to compete with others outside our group.

This evolutionary origin of morality in war is confirmed by the Bible, because Mosaic morality was shaped by the need to cooperate in war (see Deuteronomy 20:10-20, 30:15-20).