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Social scientists have proposed many different definitions of war over the years. But those definitions put forward by anthropologists usually envision war as a particular type of political relationship between groups, in which the groups use, or threaten to use, lethal force against each other in pursuit of their aims. Warfare is therefore distinct from other kinds of hostile or violent behaviour because war is made by organized collectivities rather than by individuals, and for collective ends rather than merely personal ones. To define war in this way has the very fundamental implication that the causes of war must lie in the nature of these collectivities and not in the individual.
Anthropologists have accordingly tended to reject theories based on notions of a death drive, killer instinct, or some other innate destructive or aggressive predisposition. Such theories are useless for answering the sorts of questions that anthropologists have considered central: why the frequency and intensity of war vary across time and space; why war does not occur at all in some societies; and why, where it does occur, it assumes many different forms and meanings. It is true that drive theories of aggression, implying as they do that activities such as sport, games or rituals could function as non-violent outlets for aggression, might thereby explain the absence or low incidence of war in some societies. But the evidence seems against it: there are, for instance, clear cases of societies that practise neither warfare nor any other activity inter-pretable as a mechanism of catharsis (e.g. Howell 1989).
Another approach to war is in terms of social structure, and seeks explanations in the patterning of social relations. A common theme of this tradition is that cross-cutting ties — of marriage alliance, co-residence, trade, gift-exchange or other forms of sociability — play a crucial role in limiting the frequency and intensity of warfare (e.g. Gluckman 1955). Conversely, patterns such as the ‘fraternal interest groups’ of some tribal societies — tightly knit groups of male kin, with relatively few and tenuous ties between these groups (see Ferguson 1990: 36) – seem often associated with high levels of warfare. Again, there are functionalist versions of this tradition, envisioning war as contributing to social stability by, for instance, maintaining in-group solidarity vis-a-vis the enemy.
A weakness of the social-structural tradition is that its basic intention has been to construct not theories of war at all but theories of social order or social control. That is to say, it has tended to treat peace as the central problem requiring explanation, and war as a residual phenomenon, merely the absence or failure of order. From the point of view of the theoretical understanding of war, this has been unfortunate.
The phenomenological tradition in anthropology, concerned with interpreting and translating systems of meaning, has also contributed to the study of war. This approach implies that variations in the nature and incidence of war are to be explained by cultural differences in values and beliefs. But it has failed so far to deliver a general, comparative theory. Rather, it has mostly produced sensitive ethnographic accounts of the indigenous meanings of warfare in particular societies. An example is Rosaldo’s (1980) attempt to explain headhunting among the Ilongot of the Philippines by reference to Ilongot concepts of the person and social action.
An anthropologist asked to explain war is likely to hedge their bets, and reply that it is a complex phenomenon having multiple causes rather than one. Ferguson (1990) constructed a synthetic explanation of this sort; it is essentially a resource-scarcity theory incorporating some social-structural and ideological factors.
A problem besetting attempts to construct a theory of war is that virtually every factor that has ever been posited as a cause of war can also be interpreted as an effect of it. For instance, certain kinds of expansionist warfare have been variously suggested as a cause, and as an effect,of the emergence of the state. These sorts of circularities seem to arise from trying to understand war without first having grounded it in its proper context: namely, in the deeper and more general phenomenon of violence, of which war is an aspect. An adequate theory of war must await the solution of the larger problem of the theoretical understanding of violence, which is poorly developed in anthropology.
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