He sets out to answer the "riddle of war."
Why do people engage in the deadly and destructive activity of fighting? Is it rooted in nature, or is it a late cultural invention? Have people always engaged in fighting, or did they start to do so only with the advent of agriculture, the state, and civilization? How were these, and later, major developments in human history affected by war, and, in turn, how did they affect war? Under what conditions, if at all, can war be eliminated, and is it declining at present? (p. ix)
His massive study (822 pages) of these questions is divided into three parts corresponding to the three great eras of human history: the era of hunter-gatherers, the era of agrarian civilization and pre-modern states, and the era of the modern nation-states. This first post on the book will be on the first part, which covers the history of war over two million years, the period of hunting-gathering, which constitutes over 99 per cent of human history, in which the genetic evolution of the human species was shaped.
This book has helped me to think through the evolution of war as an evolved natural desire. I have included courage in war as one of the twenty natural desires.
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. Ware 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.
Of all the desires on my list, this is the one that has provoked the most criticism from my readers, who don't like my claim that war is natural, and that it provides the conditions for displaying moral virtues like courage. Although Gat insists that his study of war has "no normative implications" (144), his reasoning generally supports my position.
We begin with the question of whether war is grounded in human nature, or whether it is a purely cultural invention of human history that transcends animal nature. To answer that question, we must look to what Gat calls the "human state of nature"--the original state of human beings living as hunter-gatherers, which was the state in which the genetic evolution of the human species was formed.
In their evolutionary natural way of life as hunter-gatherers, did humans fight? The enduring debate over this question has been divided between those on the side of Hobbes and those on the side of Rousseau. Hobbes answers that yes, the state of nature was a war of all against all, from which human beings escaped only by establishing a Leviathan state to keep the peace. Rousseau answers that no, the original condition of humans was peaceful. "Aboriginal humans lived sparsely and generally harmoniously in nature, peacefully exploiting her abundant resources. Only with the coming of agriculture, demographic growth, private property, division of class and state coercion, claimed Rousseau, did war, and all the other ills of civilization, spring up" (5).
Gat shows that Hobbes exaggerated the harshness and solitariness of the hunting-gathering way of life. Human beings are naturally social and political animals who began their evolutionary history living in families and in local and regional groups bound together by ties of kinship, language, and culture. But Gat also shows that Hobbes was right in seeing the propensity to warfare as part of the natural condition of humanity.
Thus, Gat resolves the Hobbes-Rousseau debate by concluding that Hobbes was closer to the truth, and he does this by surveying new knowledge drawn from the study of animal aggression, the study of surviving hunter-gatherers, the archaeological evidence for prehistoric hunter-gatherers, and evolutionary theory as providing a general explanatory perspective. Although he does not recognize it, Gat's depiction of the "evolutionary state of nature" conforms closely to the hunter-gatherer state of nature described by John Locke, David Hume, and Adam Smith. This is a good illustration of how modern evolutionary science can clarify, if not resolve, some of the enduring questions in the history of political philosophy.
In examining the issue of war among hunter-gatherers, Gat moves through through three questions. Did they fight? Why did they fight? How did they fight?
DID THEY FIGHT?
In the twentieth century, the anthropological study of war was dominated by the Rousseauean claim that warfare was a recent cultural invention in human history that was not rooted in human nature. Lawrence Keeley's War and Civilization: The Myth of the Peaceful Savage (1996) challenged this view with overwhelming evidence of warfare in pre-state societies. But Keeley's argument was weakened by the fact that he concentrated on the Neolithic period, when people adopted agriculture and animal husbandry (about 10,000 years ago), but before the establishment of states. The Rousseaueans could argue that it was the transition to agriculture that was crucial to the emergence of war, because this brought valuable stored food and other property that was worth fighting for. Consequently, the evidence of war in pre-state agricultural societies might not apply to hunter-gatherers who lived prior to 10,000 years ago.
Gat's contribution here is to extend the evidence for warfare back into hunter-gatherer history. Hunter-gatherer society consisted of local groups (20-70 members) and regional groups (an average of 500 members), bound together by language, intermarriage, rituals, exchange, alliances, and military activity. They were nomadic, and they had few possessions. Although they were remarkably egalitarian, because there was no formal and fixed status hierarchy, these societies were not totally equal, because some people who were talented and ambitious could exercise leadership, particularly in war (14, 22, 26, 32, 71-72, 74, 88-92, 138).
Gat's claim about hunter-gatherer warfare is qualified. His claim is "not that all hunter-gatherers invariably fight," because he recognizes that in all human societies throughout history, there are long periods of peace. Here is where Gat disagrees with Konrad Lorenz and others who have argued that human beings have an instinct for killing that must invariably be satisfied in some way. But Gat does claim that there has always been warfare from time to time.
The problem, however, is that the knowledge of the hunting-gathering way of life in the Pleistocene era (from two million to 10,000 years ago) is inherently inconclusive. There is some archaeological evidence for war--for example, burial remains of people apparently killed by violence and rock art depictions of war. The studies of historically recorded hunter-gatherers also shows evidence for war. But here we face the "contact paradox": since hunter-gatherers have no written records, documentary evidence depends on contact with literate people, and this contact can "contaminate" what is being observed. Consequently, the Rousseaueans can always argue that what we see of hunter-gatherers after contact is not the true story of what they looked like before contact.
To overcome this problem, Gat looks for a natural "laboratory"--a case where we can see a hunter-gatherer society that has experienced little or no change from contact with literate people. Gat sees two such "laboratory" cases. The first case is of the "simple" hunter-gatherers in Australia. The second is of "complex" hunter-gatherers in the Pacific Northwest of North America. Although much of the anthropological debate over hunter-gatherers has been dominated by the case of the African Bushmen, Gat rightly insists that it's not the best case to study because the Bushmen had been pushed into desolate environments by competition with other groups.
When Europeans began arriving in Australia in 1788, the remote areas of the interior and the north were the locales for hunter-gatherers who had no agriculture or pastoralism. There were as many as 300,000 hunter-gatherers, in 400-700 regional groups, with 500-600 people each. Their lives were simple. They didn't even have bows. Their only long-range weapon was the boomerang. Although nomadic, their movements were within a circumscribed territory, and they enforced the boundaries of their group territories.
Among these Australian aboriginals, there were violent disputes based on women, murder, and territorial trespass. Although each group enforced a rough equality, there were differences in status and influence, as in leadership by the most skillful warriors. There were trading networks extending over long distances.
The high rates of killing in war was first reported by William Buckley, who arrived in Australia in 1803 as a 13-year-old-boy from England on the first convict ship. Buckley escaped and lived with an Aboriginal tribe for 35 years. He learned their language and participated in their daily activities. Later, his reports on his experiences were recorded. And while there is some dispute over the accuracy of his stories, this seems to be the best account of a hunting-gathering society before any extensive contact with literate people. Buckley's testimony supports Gat's claim that even the simplest kind of hunting-gathering society showed warfare.
A more "complex" form of hunting-gathering society arises in rich wildlife areas, such as swamps, lakes, river mouths, and seashores. In such rich ecological niches, human population can be dense, life is more sedentary, food is accumulated, there is extensive division of labor, trade, and property, with rich individuals exercising control over resources.
The Indians of the Pacific Northwest coast of North America show this kind of society, and they show evidence of warfare and slavery through war stretching back for thousands of years.
This evidence shows that for both "simple" and "complex" hunter-gatherers, warfare was part of the "evolutionary natural way of life."
WHY DID THEY FIGHT?
I agree with Gat that--contrary to Freud, Lorenz, Tinbergen, and Storr--there is no "basic aggression instinct" comparable to the instinctive drives for food and sex. The drives for food and sex are unavoidable. But people can live in peace their entire lives without feeling any distress. Aggression is not a biological end, but a biological means to the primary biological ends.
War is "both innate and optional" (40). It is innate, because humans are naturally inclined to go to war whenever the benefits of war seem greater than the costs. Yet war is optional, because it fluctuates in response to changing conditions of life.
The evolution of war required group selection in which groups bound together by kinship relations, marriage, and cultural identity competed with one another. Religion can be understood as an evolutionary adaptation for cooperation in group selection. Gat agrees with the group-selection explanation of religion developed by David Sloan Wilson, although Gat notes that Wilson "overlooks the military aspect" of this.
Over the past thirty or forty years, there has been an intense debate among anthropologists as to the motivations for war in primitive societies. Some materialist anthropologists like Marvin Harris have stressed the importance of competition for food. Some evolutionary anthropologists like Napoleon Chagnon have stressed the importance of competition for women. According to Chagnon, when he asked Yanomamo men about this, they answered: "We like meat, but we like women a whole lot more."
Gat rightly points out that Chagnon was only partially correct about this, because he did not see how evolutionary theory allows us to see how many different factors can influence war. Evolutionary science suggests that the ultimate causes of adaptive human behavior are either somatic (concerned with the resources necessary for survival) or reproductive (concerned with mating and offspring). Thus, food and sex are primary needs or desires.
Yet there are also many secondary motivations for war that are ultimately instrumental (from the evolutionary perspective) to the somatic and reproductive motivations. These secondary motivations include dominance, revenge, fear, suspicion, supernatural elements, cannibalism, playfulness, adventurism, sadism, and ecstasy.
I see these secondary motivations as tied to various natural desires on my list of twenty--such as social status, political rule, justice as reciprocity, property, and the desire for religious understanding. I also agree with Gat that many of these motivations reflect the distinctly male propensities for risky violence and adventure.
Although the evolutionary explanation of war assumes that military violence is generally adaptive, it also recognizes that there is a lot of maladaptive and purposeless violence. So, for example, the sadism that is sometimes manifest in war can be understood as a deviation from an evolutionarily shaped norm.
HOW DID THEY FIGHT?
Human hunter-gatherers show a pattern of warfare similar to that of chimpanzees. Young adult males form raiding parties that attack only when they outnumber their opponents and thus can minimize the risk to themselves. When opposing groups face one another in open lines of battle, they prefer to engage in ritualistic bluffing displays, rather than going to battle.
There is one crucial difference between the humans and the chimps, however, in that among the human hunter-gatherers, there is a higher rate of mortality for adults. Gat identifies this as a pattern of "asymmetrical, first-strike killing." Hunter-gatherer warriors prefer to launch surprise attacks on their enemies--typically, at night when their victims are asleep and thus vulnerable.
The difference between humans and other animals is that human tool-making allows the humans to increase their offensive capability. But this also makes humans more vulnerable to attack, because as humans become more dependent on tools, their bodies become more slender and less robust than is the case for their primate ancestors. Adult male chimps carry their weapons in their bodies--powerful jaws and a physically strong build. Adult male humans lose this, and thus they become vulnerable to surprise attacks.
As a consequence, human hunter-gatherers are caught in what international relations theorists call the "security dilemma": they live in a state of fear and distrust, anticipating that they are vulnerable to surprise attacks, which inclines them to pre-emptive strikes, which only increases the state of mutual distrust. Thus, they are caught in a kind of "prisoner's dilemma" situation, where everyone is worse off than they would be if they could trust one another to cooperatively keep the peace. Hobbes saw this, and this is what led him to his dark view of the state of nature as full of fear and continual dangers.
Gat concludes this first part of his book by insisting that "the evolutionary logic in itself has no normative implications."
We may choose to follow such predispositions or rebel against them. There is nothing sacred or morally compelling about maximizing survival for the fittest. This is merely the blind, algorithmic mechanism of natural 'design.' The human brain--itself a product of evolution and a powerful instrument of conscious, purposeful, and future oriented, rather than blind, design--may come up with more satisfactory arrangements. (144)
Gat doesn't explain exactly what he has in mind here. Obviously, he is doing what evolutionary psychologists often do to avoid questions about the moral implications of their work: invoke the fact-value distinction and declare that, of course, human beings are free to appeal to moral values formulated by human reason as transcending the factual world of empirical science. But this seems to leave us with a radical dualism where the moral realm of human rational artifice floats free of the natural world. If this is so, then what is most distinctly human cannot be explained by science because it belongs to some kind of transcendental realm--perhaps Kant's realm of human freedom.
I agree that human beings do have some freedom of judgment that comes from their capacity for deliberate thought and choice. But I argue that this human freedom of judgment is constrained both by human nature and by human culture. So, in matters of war and peace, we can look for ways to promote peace and minimize war. But given our natural propensities towards war when we face severe conflicts between groups, we cannot realistically expect to achieve a world of perpetual peace.
Some posts on related topics can be found here, here, here, and here.