Blood Rites: Origins and History of the Passions of War, by Barbara Ehrenreich, Virago 292pp, £18.99 in UK
Why are men attracted to war, violence, sexual variety and rape rather more than women? Is it in our genes or in our heads? Sociobiologists, and evolutionary psychologists such as Steven Pinker in his recent celebrity lecture in Dublin, seem to think it is both. Primitive pressures have not just selected our physical capacities, but fashioned our perceptions, attitudes, values as well, impelled by the same elemental logic of self-reproduction which made us walk tall and see straight.
Like Pinker, Barbara Ehrenreich views her topic in the light of Darwin and Dawkins, of genes and their impact on how we think and order the world. That topic is war and the passion which has replicated itself irremediably through the generations of humans who have slaughtered and been killed to appease it.
She has written an extraordinary book, original and witty, stuffed with stories of ancestral weirdos and their behavioural links with modern descendants.
The book divides into a first section which examines the evidence for a formative experience in prehistory, conditioning humans in their gender-related attitudes to war, and a second part which relates modern attitudes and institutions of belligerence to ancient myths and terrors. Blood is the key. Its colour and smell, the thrill and the fear of its spilling and shedding, are brought to life in vivid descriptions which Ehrenreich brings to her story.
It all started with hunting. Unlike Pinker and most sociobiologists, however, Ehrenreich believes that the thrill of the hunt and the appetites of the gods for carnal sacrifice came late in the evolutionary chain. For much longer before that, the human mind was imprinted with the terror of being hunted, of being the prey rather than the predator. Panic and solidarity against the enemy are the two psychological legacies of this ancient past.
The great shift to specialised hunting did indeed bring with it the gender roles which allocated women to the primitive hearth and men to the bellicose arts, but not, as we believe, out of the dual necessity of nurture and hunger. As far back as the Palaeolithic age, men had an identity problem, which they solved by investing blood and its letting with sacral meaning, which gave to males a priestly role in the sphere of public order and reinterpreted the diffuse domestic skills of women.
The spear, the sling, and later the horse, did it for women. Violence and the lust for blood are as natural to them as to men, according to Ehrenreich, but it was the institution of war which made them a male prerogative. Even women's menstrual bleeding, once revered, now had to be hidden. The blood of males became a sacrament, that of females a dangerous pollutant.
Is war, then, a determinate outcome of biology? Cormac McCarthy has written: "War endures. As well ask men what they think of stone. War was always here. Before man was, war waited for him." Ehrenreich seems to disagree. Whatever about violence, war has no genetic determinant. It is all in the jeans.
There is something at once shocking and intellectually exciting about sociobiology, which makes the mind - and not just the brain - an effect of selfish genes. The thrill lies in its promise of shaking the foundations of everyday certainties. The shock in our awareness of its moral consequences. And Ehrenreich's is a shocking and gripping narrative. But there must be some question about the plausibility of the argument and the selective sources adduced to support it. As with Dawkins and Pinker, it is not easy here to pin down exactly the claims being made.
Ehrenreich wants to have it both ways. She wants to shock without being silly. The biologist in her wants to show that our capacity for evil is written in our genes - "a self-replicating pattern of behaviour, possessed of a dynamism not unlike that of living things". ("Not unlike" gives the game away, surely?) The weakness of the evidence makes her back off from determinism in favour of common sense. We can redirect or transform the self-replicating character of culture, she concedes.
Indeed we can. And we can explain it also without drawing on unwarranted extrapolations from genetics to social theory which conflate the superficial similarities between the purposeless reproduction of cells and the purposeful reproduction of ideas, values, and institutions.
Bill McSweeney is head of the MPhil (Peace Studies) programme of the Irish School of Ecumenics; his edited volume Moral Issues in International Affairs will be published shortly