In Why War?, Richard Overy draws upon his lifetime as a war historian to summarise what research across multiple disciplines can tell us about the causes and motives for war. The result is an absorbing exploration of human biological, psychological and cultural propensities for collective violence, as well as the main motives that have animated warfare throughout history.
The likelihood that humans have adapted biologically to engage in collective violence, when necessary to ensure survival, seems to be the first building block in explaining war. It seems plausible that during our evolution, coalitional violence would have increased the likelihood that particular groups survived under conditions where survival was a struggle. During our long prehistory, humans experienced repeated periods of glaciation and other severe environmental challenges where populations were significantly reduced. Violence in this context may have had adaptive value by increasing access to resources such as food and territory, as well as fending off threats from other humans. During our long evolution, traits for violence, when necessary, as well as traits for sociality and co-operation, were therefore likely selected for at both individual and group levels. In this view, violence and co-operation are not opposites, but two elements of an evolutionary package we developed over hundreds of thousands of years. As a consequence, human nature is both potentially aggressive and destructive, and potentially co-operative and empathetic.
Importantly, Overy dismisses two dangerous ideas, mistakenly derived from Darwin’s theory of natural selection. These are that we are genetically programmed for violence and war, and that war is a natural biological phenomenon, a means of evolutionary competition to sort the strong from the weak. These were Hitler’s views, for example, and they underpinned his programmes of extermination of the old and infirm, the Holocaust and his wars to the death between “races”. There is no scientific evidence for either idea.
Within the last few thousand years, our separate instincts for religiosity and morality have not always been linked. In fact, the link between them is culturally created and has changed dramatically during recorded history
The human biological imperative to fight when necessary has been reinforced by our evolved psychology which enables such violence. Among the features of our psychological make-up are a disposition to accept collective violence, particularly by males, alongside a capacity for dehumanising others, particularly those we deem to be a threat. As is the case with our biology, our psychology has developed in response to selection pressures related to both collaborative living and competition for survival, and therefore allows us to be both co-operative and confrontational. An important insight from evolutionary psychology is that our behaviour is a conditional response to the context we find ourselves in. Some contexts can stimulate violent responses, other contexts can stimulate sociality and co-operativeness.
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In our species’ more recent history, culture rather than natural selection has come to be the key influence on our collective behaviour. Strikingly, the archaeological and anthropological evidence strongly suggests that the co-evolution of culture with our biological and cultural dispositions towards violence resulted, early in our species’ historical record, in the emergence everywhere of hierarchical societies headed by warrior elites, with men acting overwhelmingly as the perpetrators of violence.
One key feature of this hierarchical culture has been the persistence throughout history of what Overy calls hubristic warfare – war led by men in pursuit of individual power and glory. Alexander the Great, Napoleon and Hitler are just three examples he cites of hubristic individuals who led violent conquests for empire, fuelled by unbridled narcissism and an insatiable appetite for glory. One could add Vladimir Putin to a very much longer list.
The French philosopher Alain Badiou has called this highly unequal, hierarchical social structure that humans have been living in since the dawn of recorded history “the Neolithic”. It comprises a small, violent elite in whose hands power and wealth are concentrated, a sizeable middle class who benefit from the system, and a majority of poor and dispossessed who spend their lives supporting the lifestyles of those above them. This unjust and unequal social order, Badiou argues, is responsible for humanity’s unending wars and environmental destruction, and has now brought us to the brink of catastrophe.
Why such a system emerged, why it has persisted until the present day, and whether or not we can escape it, are the central questions in Harvey Whitehouse’s fascinating book Inheritance: The Evolutionary Origins of the Modern World. Whitehouse agrees with Overy that a combination of our biologically evolved instincts and culturally evolved traditions constitutes our collective inheritance as a species. Inheritance focuses on three of these instincts, namely conformism – the fact that we avidly follow others; religiosity – that we are naturally inclined towards religious ways of thinking; and tribalism – our passionate loyalty to groups.
Whitehouse’s argument is not one of determinism – that these propensities necessarily result in a single outcome. As an anthropologist, he is deeply aware of the myriad varieties of cultural systems that human societies have constructed across history and around the world. But he does argue that our natural biases – to conform, to believe and to belong – have deeply shaped the trajectory of human cultural evolution, including the emergence and persistence of Badiou’s Neolithic social order. Could the very same features of human nature that have brought us to the brink, Whitehouse also asks, be harnessed to fundamentally reshape our civilisation to one more conducive to human flourishing?
Whitehouse explores these topics from various angles, addressing the role of ritual, the role of intense emotional experiences in forging violent groups, and the possibility of fundamentally reimagining the materialistic basis of society. But the most fascinating part of Inheritance explores the connection between violence and religion.
His argument is nuanced and runs as follows. We humans have innate predispositions for both religiosity and morality. Our predispositions for religiosity include our tendency to believe in the supernatural, to regard certain people, places and objects as sacred, to believe in life after death and to ascribe supernatural design to nature, that is, to see the hand of a creator everywhere.
Separately, we have an innate morality. Whitehouse summarises research on 60 societies that have been extensively studied by anthropologists which suggests that our innate morality is based on seven core principles, all rooted in the necessity for co-operation: help your kin, be loyal to your group, reciprocate favours, be courageous, defer to superiors, share things fairly and respect other people’s property.
Both our religiosity and our moral intuitions are the products of our biological, psychological and social evolution. They both evolved over hundreds of thousands of years because of their benefits for our survival and reproduction.
However, during our more recent journey of cultural evolution, within the last few thousand years, our separate instincts for religiosity and morality have not always been linked. In fact, the link between them is culturally created and has changed dramatically during recorded history. This history shows us that organised religion can either promote or undermine our innate morality.
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In Whitehouse’s telling, from the beginning, ruling elites capitalised on our innate religiosity to claim that their power was sanctioned by the gods. Few ancient cultures did not have a god or gods of war and warrior cults where violence was divinely sanctioned. The ancient gods that violent elites called upon typically had little interest in us as individuals, nor did they care about our behaviour. They were more akin to insecure, unstable narcissists demanding our worship and submission.
Among the features of our psychological make-up are a disposition to accept collective violence, particularly by males, alongside a capacity for dehumanising others, particularly those we deem to be a threat
A fascinating turn in our species’ cultural evolution occurred, however, with the emergence of what Whitehouse calls moralising religions. During the so-called Axial Age, a new set of religious and philosophical values began to appear and spread among the world’s largest empires, challenging the hegemony of rulers and articulating a vision of greater social justice. The Axial Age was the time when what are now the world’s big religions – Christianity, Buddhism, Islam and Confucianism – emerged in opposition to the rule of violent leaders, injustice and inequality. These moralising religions aligned much more strongly with our innate morality and provided a platform upon which humanity’s long struggle to escape the tyranny of violent hubristic leaders and the structural violence of the “Neolithic” social order began.
Unfortunately, as we know, the story did not follow a simple, linear narrative. Since their emergence, moralising religions have also been co-opted by empires and states to justify violence in the name of tyranny and injustice. This Janus-faced aspect of religion, in which it both upholds and opposes violence and inequality, continues to the present day.
At the beginning of Why War?, Overy cautions the reader that he is stepping outside his area of specialist expertise to surmise on the broad sweep of history. Whitehouse too ranges widely across disciplines and timescales to formulate his exhilarating narrative of human history. It is to our immense benefit that they have done so. Not only have both authors produced works that are enthralling and mind-expanding, Why War? and Inheritance are also books of profound value.
Ian Hughes is author of Disordered Minds: How Dangerous Personalities Are Destroying Democracy
Further reading
A New Dawn for Politics by Alain Badiou (Polity, 2022) argues that modern democracies are simply the latest iteration of the “Neolithic” social structure that upholds both the blatantly unjust nature of the global system and the immense concentration of wealth in the hands of a few. Challenging this fundamental structure would truly herald a new dawn for politics.
The Dawn of Everything: A New History of Humanity by David Graeber and David Wengrow (Penguin, 2022) is an immensely ambitious and captivating narrative of human cultural history. It tells how our ancestors throughout prehistory were acutely aware of the dangers of authoritarianism, and were able to maintain, for thousands of years, social structures to guard against it.
The Great Transformation: The World in the Time of Buddha, Socrates. Confucius and Jeremiah by historian of religion Karen Armstrong (Atlantic Books, 2007) explores the Axial Age, which saw the explosion of new religious and moral concepts that began to challenge social injustice and the power of violent rulers.
Out of Our Minds: What We Think and How We Came to Think It by Felipe Fernández-Armesto (Oneworld, 2020) brings us on a journey through the history of ideas from prehistory to the present. Ranging across the themes of spirituality, organisation of society, human nature, science and morality, it shows that history has been shaped by ideas so powerful that they have impelled us to reshape our world.
