darwinian fallacies

prospect, december 1998

'Boys are made to squirt and girls are made to lay eggs. And if the truth be known, boys don't very much care what they squirt into.' Crude and inelegant it may be, but Gore Vidal's pithy quote neatly sums up the argument of evolutionary psychology.

The human mind is built from genes, the argument goes, the sole purpose of which is to reproduce themselves. The genes, which have been selected for through the process of evolution, programme the mind with a set of behaviours best designed to carry out their selfish aims. The reproductive strategies of men and women are different, so they have been programmed to exhibit different behaviours. The whole edifice of human society and culture is built on the need for genes to reproduce themselves, and on the different needs of men and women.

It is an argument that might strike some people as being at least as crude and inelegant as Vidal's summary, but it is one that has become increasingly acceptable, fashionable even. Darwinian thinkers like Richard Dawkins and Steven Pinker have become science superstars. A multitude of non-scientists, including Booker Prize winner Ian McEwan and broadcaster Melvyn Bragg have become proselytisers for the new vision of Man. From Cosmo to Time the media has been increasingly seduced by the charms of the new science. Leading evolutionary psychologists regularly pitch in with the Darwinian view on contemporary political debates, from Richard Wilkinson discussing the evolutionary basis of health inequalities to Steven Pinker ruminating in New Yorker magazine on the evolutionary significance of Bill sharing a cigar with Monica.

Fashionable, perhaps, but is it credible? That's the question I want to address in this essay by looking at three basic premises of evolutionary psychology. First, that human beings are not born as blank slates, but are preprogrammed with specific knowledge about the world into which they are about to enter. Second, that most human behaviours, as well as social structures, have been selected for through the course of evolution, and that the ultimate (if not proximate) cause of such behaviour is the need to spread genes. And third, that many of the social problems which beset humanity arise from the mismatch between our genetic heritage (which is adapted for a Stone Age environment) and the world in which we live today. In effect we are Stone Age men living in a space age world. The first argument, I want to show, is largely correct, the second largely wrong, and third is specious nonsense.

For most of the past half-century, the orthodox view within psychology, anthropology and social science has been that human beings are born as blank slates. The human infant learns entirely through experience, and its behaviours, attitudes and personality are moulded wholly by the culture into which it is born. Most scientists acknowledged that humans had a number of basic instincts and an innate propensity to learn, but felt that these did not amount to much given the almost infinitely plastic and impressionable nature of the mind. Finally, according to this orthodox view, the human brain works like a general purpose computer, using much the same method of reasoning to tackle every problem, whether reading a book or making a marriage proposal. Few went as far as Jean-Paul Sartre who claimed that 'there is no human nature... Man simply is. He is what he wills.' But the spirit of Sartre's sentiment has infused much of what Darwinists today dismissively dub the Standard Social Science Model, or SSSM.

In recent decades it has become increasingly clear that the blank slate view of the human mind is untenable. A human infant which began life with an empty head would be in a similar predicament to Funes, a character in a Jorge Luis Borges story. Funes never forgot anything, and subsequently spent the whole day recalling the events of the previous day. The infant, similarly, would not know which stimuli to attend to, and which to ignore, or how to transform relevant stimuli into meaningful perceptions, ideas and concepts. An infant, therefore, like Funes, needs a mechanism to filter incoming data and to attach meaning to them. It would already have to know something about the world into which it is about to be born.

Over the past two decades psychologists have devised ever more inventive experiments to tease out what this 'something' might be. We now know, for instance, that infants possess knowledge about the physical world that they could not possibly have acquired through experience. They know what constitutes a physical an object, that objects do not normally pass through each other, and that they do not normally materialise or dematerialise at will. Infants seem to have an innate concept of the difference between animate and inanimate objects, and an intuitive preference for the human face.

Perhaps the most spectacular advance in the understanding of innate knowledge has been with an infant's linguistic ability. Forty years ago Noam Chomsky instigated a revolution in cognitive psychology by suggesting that children learn language by learning rules of grammar. These rules, he suggested, are somehow hardwired into the brain. Chomsky called these innate rules a 'universal grammar' and suggested that the same universal grammar underlay all human languages.

Over the past four decades Chomsky's insights have proved very fruitful. Research from a variety of disciplines has shown linguistic capacity to be both natural and universal. It is natural because it is almost impossible to stop a child learning its native tongue. When a child encounters maths, it has to memorise the multiplication table and the complexities of long division. When it learns to play the piano, it must laboriously learn the notes and the chords and then the way that these combine to form musical phrases. Yet when it learns its native language, it uses such complex grammatical constructions such as the conditional subjunctive, or the past perfect tense without knowing that it is doing so, and possibly without ever knowing in its lifetime that it has done so thousands of times over.

Language is universal because not only do all human cultures possess language, but they possess language of similar complexity. As the anthropological linguist Edward Sapir put it, 'When this comes to linguistic form, Plato walks with the Macedonian swineherd, Confucius with the headhunting savage of Assam.' Unlike reading or mathematics or engineering, the sophistication of language is not altered by historical or social development. Language, therefore, seems to be both distinct from other cognitive skills and innate.

All these considerations have led cognitive psychologists to replace the blank slate with a 'modular' view of the mind. The mind possesses innate knowledge about the world. This knowledge is contained in a collection of distinct modules, or mini-minds, each specialised to perform a distinct task: understand physical relations, analyse visual data, process speech, and so on. Most cognitive psychologists believe that the mind is only partly modular - largely in the processing of language, perception and emotion. Cognition, many argue, results from more general brain processes.

Not so, respond evolutionary psychologists. Virtually all thought processes, they suggest, are modular and innate. Moreover, they argue, modules are not simply innate (hardwired into the brain) but evolved (designed by natural selection to perform functions important to the survival and reproduction of the organism).

The starting point of evolutionary psychology is not so much how the brain works today, as how it would have worked some 50 000 years ago. The brain, they observe, is an evolved structure and it evolved to solve the problems characteristic of our hunter-gatherer past. 'Evolutionary processes are the "architect" that assembled, detail by detail, our evolved psychological and physiological architecture', the psychologists Leda Cosmides and John Tooby wrote in their landmark paper 'The psychological foundations of culture'.

Because each type of problem faced by our Stone Age ancestors had a unique form, trying to solve them all with a single reasoning device would not have been very useful. The most successful early humans would have been those individuals whose brains provided specific solutions to specific problems. In other words, the smartest ancient human brains would have been composed of dozens of different instincts (or 'modules'), each designed by natural selection to aid survival and reproduction in a Stone Age environment. For evolutionary psychologists all human behaviours are adaptive - they were chosen by natural selection because they increased the ability of the individual to reproduce. According to Cosmides and Tooby, these ancient modules would have included ones for 'face recognition, spatial relations, rigid object mechanics, tool-use, fear, social exchange, emotion perception, kin-oriented motivation, effort allocation and recalibration, child care, social inference, sexual attraction, semantic inference, friendship, grammar acquisition, communications-pragmatics, and theory of mind'.

Since the modern mind is not genetically that different from that of our ancestors, Cosmides and Tooby argue, so our minds too must be comprised of these modules. As with our ancestors, our mind is a nest of instincts, all adapted for a Stone Age life.

The Cosmides and Tooby model makes for an interesting, and in some ways a plausible, theory. The trouble is, it simply does not necessarily fit in with what we know about the ways in which the human mind actually works. The modern mind is characterised not by its modularity - a capacity to respond to many tasks in a fast but rigid fashion - but by its flexibility, an ability to think laterally, and to use analogy and metaphor.

Take, for instance, something as basic children's play. 'Give a child a doll and she will start talking to it, feeding it and changing its nappy', the archaeologist Steven Mithen points out. 'That inert lump of moulded plastic never smiles at her, but she seems to use the same mental process for interacting with it as she does for interacting with real people.' In the evolutionary psychology scheme of things, the brain contains two innate, specialist modules, one of which allows us to deal with animate objects, and the other with inanimate ones. There is some empirical evidence that this may be the case. But in treating an inanimate doll as if it were an animate being, the child is seems to be tearing up the psychologists' blueprint. She is displaying a form of lateral thinking not permitted by a strict modular model. Had our ancestors also mistaken inanimate objects for animate ones, they would not have survived for very long, and we would not be here, debating this point.

Evolutionary psychologists respond that their critics misunderstand the nature of flexibility. 'Having a lot of built-in machinery', Steven Pinker argues, 'should make a system respond more intelligently and flexibly to its inputs, not less'. Humans are intelligent 'not because we have fewer instincts than other animals but because we have more. Our vaunted flexibility comes from scores of instincts assembled into programmes and pitted in competition.'

This, however, misses the point. Human flexibility arises not because our various instincts are allowed to compete with each other, but because we are able to integrate and eventually transcend the disparate views available to any single module or instinct. It is this ability to create a more integrated view of the world that we call reasoning. By definition modular problem-solving works with less than all the information that a creature possesses. Eventually, however, the mind has to synthesize the results of all those modular computations to create a human-like view of the world. And this, as the philosopher Jerry Fodor points out, cannot be a modular process.

Fodor was one of the original proponents of the modular view of the mind. But he is highly critical of contemporary evolutionary psychology, because of its advocacy of what he has dubbed 'massive modularity'. In his early work, Fodor used the existence of visual illusions as an argument for the existence of modules. Even though we know that certain things are illusions, we cannot see them in any other way, however hard we may try. Vision, therefore, seems to work independently of other types of knowledge; in other words it seems to work as an isolated module.

But our very ability to recognise that an illusion is not real, Fodor points out, shows that there must be more to cognition that the work of modules:

The moon looks bigger when it's on the horizon; but I know perfectly well that it's not. My visual perception module gets fooled, but I don't. The question is : who is this I? And by what - presumably global - computational process does it use what I know about astronomical facts to correct the misleading appearances that my visual perception insists on computing? If, in short, there is a community of computers living in my head, there had better be somebody in charge; and by God it had better be me.

Fodor is suggesting that a brain full of modules, and only full of modules, could not give rise to self awareness. And self-awareness, as we shall see later, is crucial in understanding what it means to be human.

Human beings possess innate knowledge about our world. The human mind, to some degree at least, is composed of specialised modules, each dedicated to solving particular tasks. But there seems to be little wisdom in viewing the mind simply as a nest of instincts. There is, on the contrary, considerable reason, both empirical and theoretical, to believe that the mind cannot be built in the way the evolutionary psychologists wish it to be. While language and basic perceptual systems such as vision or the understanding of physical systems, have been shown to be modular, very little else has. Certainly, there is little evidence that the higher level cognitive skills on Cosmides and Tooby's list exist as modules in the mind.

The second premise of evolutionary psychology – that human behaviours and social structures are solely the products of natural selection - is even more problematic. This claim rests on two beliefs: first that modern behaviours are analogous to those of our ancestors; and second, that, short of evoking Divine intervention, natural selection is the only force that could have shaped the human mind and society. Like the claim for a modular mind, this argument is based on a view of how humans would have conducted themselves 50 000 years ago. But how do we know the behaviour of our ancestors? Behaviour, unlike bone, does not fossilise. Precisely because these are ancient humans, living before the development of much technology, archaeological evidence is scant. And there are certainly no ancient humans still living for us to observe.

It's a problem faced by many disciplines - archaeology, for instance, or palaeoanthropology - which have to reconstruct an ancient past from scant evidence. But it is a particular problem for evolutionary psychologists because their whole discipline rests on understanding modern behaviour in the light of ancient behaviour.

There are a number of ways evolutionary psychologists try to get round this problem. One is to assume that the lives of contemporary hunter-gatherers, such as the !Kung San of southern Africa or the Ache of South America, provide a window onto the lives our ancestors. Since humans, over the vast proportion of our evolutionary history, lived as hunter-gatherers, so any evolved behaviours would be adaptations to a hunter-gatherer life. Hence studying the behaviours of contemporary hunter-gatherers should tell us which modern behaviours are adaptive and which not.

There is a long history of psychologists and anthropologists viewing 'primitive' groups as relics of an ancient past. It's a claim at the heart of nineteenth-century racial anthropology. I am not suggesting that the arguments of evolutionary psychologists are racist in any way - far from it. But many of the problems that underlay racial anthropology also underlie evolutionary psychology.

To begin with, why should we assume that the lives of 'primitive' societies today resemble those of ancient humans? Both may be hunter-gatherers, but the !Kung San, the Ache and others, are likely to have changed and developed over the past fifty or hundred thousand years. After all, no one would claim that modern agricultural societies resemble those of the earliest farmers ten thousand years ago. Why make the same assumption about hunter-gatherers, especially over a much greater time span?

There are many reasons to question the assumption that the psychological traits and behaviours of contemporary hunter-gatherers are necessarily evolved adaptations. Consider, for instance, the claim by some Darwinists that we possess an 'intuitive biology' module - an innate evolved capacity to understand and order the natural world. A number of anthropologists have pointed out the remarkable similarities between the way that 'primitive' societies classify the living world and the Linnaean system of classification at the heart of modern biology. According to Scott Atran, cross-cultural studies suggest that people universally group local plants and animals into kinds that correspond to the genus level in the Linnaean classification. People also classify kinds into higher level forms such as trees, grass, birds, fish, quadrupeds, and so on, many of which coincide with the biologist's notion of class.

For evolutionary psychologists, the fact that hunter-gatherers have developed such superb taxonomic skills without the benefits of modern science reveals these skills to be innate and evolved. But if this were true, then, given their common genetic constitution, people living in modern industrial nations should be as capable as hunter-gatherers of classifying animals and plants. Quite clearly, they are not. Put the average Englishman on a desert island and you’d quickly find that his 'natural' abilities were less than intuitive.

The taxonomic skills of hunter-gatherers may well be inherited through their cultures not their genes. Evolutionary psychologists are confusing innate knowledge with folk knowledge - the knowledge developed within non-scientific cultures. Folk knowledge, such as that of hunter-gatherers, they assume, must be intuitive. But why? Non-scientific peoples are as capable of reasoning about the natural world as are scientists. The empirical reality of the biological world, together with a common propensity of human cultures to categorise at some minimal level (a propensity that may or may not be innate) is sufficient to explain similar taxonomies among different peoples. It is simply nonsense for Steven Pinker to write that because 'Most people feel, along with biologists, that the caterpillar and butterfly are the same animal, and the caterpillar and centipede are not, despite appearances to the contrary', so this demonstrates an 'intuitive' capacity to classify living forms. In fact, it simply demonstrates that we have learned that caterpillars give rise to butterflies but are unrelated to centipedes, just as we learn that whales should be classified not with fish but with mammals - and just as Australian Aborigines or the !Kung San learn the differences between birds, fish and quadrupeds.

The absurdities of using contemporary hunter-gatherers as templates for ancient humans can be seen in an example in EO Wilson's book On Human Nature. Here, Wilson examines sexual roles among the !Kung San. Wilson observes that the !Kung do not impose sex roles upon their children, little girls apparently being treated in much the same manner as little boys. As adults, women gather mongongo nuts and other plant food, usually close to the camp, while men range further to hunt game. But, writes Wilson, '!Kung social life is relaxed and egalitarian and social tasks are often shared. Men often gather mongongo nuts or build huts... and women occasionally catch small game.'

!Kung San society, then, shows some but not much sexual differentiation. Where, however, the !Kung San have settled into an agricultural form of life, the sexual roles are much more entrenched. Wilson suggests that as societies develop, so sexual roles become more demarcated: 'When societies grow still larger and more complex, women tend to be reduced in influence outside the home, and to be more constrained by custom, ritual and formal life.'

Wilson's claim that social complexity necessarily leads to greater sexual differentiation may be somewhat dubious but it is not a totally unwarranted assumption. A reasonable interpretation of this might be that sexual differentiation is a product of social development. To find the causes of the subordination of women in modern society, then, one should look at the organisation of modern society.

This, however, is not Wilson's conclusion. According to Wilson sexual differentiation is the product of a natural process - hypertrophy. Hypertrophy normally refers to an increase in the size of a tissue or organ, often in response to an increased workload. A similar process, Wilson suggests, has led to sexual differentiation in modern societies. 'Like the teeth of baby elephants that lengthen into tusks, and the cranial bones of the male elk that sprout into astonishing great antlers', he writes, 'the basic social responses of the hunter-gatherers have metamorphosed from relatively modest environmental adaptations into unexpectedly elaborate, even monstrous forms in advanced societies.'

Speculation may be the stock in trade of evolutionary psychology, but even by Darwinian standards this is spectacularly wild. To begin with, hypertrophy is a developmental, not evolutionary, process. It refers to a process that takes place within an individual's lifetime, not within a species across evolutionary time. It also refers to a process of physical, not a behavioural or social, change. As a scientific theory goes, it's about on par with the belief that aliens built the pyramids. None of this prevents Wilson from arguing that a whole host of other social phenomena, including racism and nationalism, are also 'hypertrophic modifications of the biologically meaningful institutions of hunter-gatherer bands and early tribal states.' It's an argument that belongs more to the Eric von Daniken school of science-as-wishful-thinking than to any theory derived from Charles Darwin.

What Wilson is really doing is taking a modern behaviour - in this case sexual discrimination - translating it back into hunter-gatherer life, and assuming that these early behaviours must be 'biologically meaningful' since the only force acting on ancient humans was natural selection. He then notices that the same behaviour appears in modern humans. So, hey presto! the modern behaviour must also be the result of natural selection. When the conclusion is smuggled into the method, it is not surprising if you always end up with the conclusion that you desire - in this case that modern human behaviour is the product of natural selection.

This circularity is common to much of evolutionary psychology thinking. Take, for instance, Cosmides and Tooby's list of modules. How do they know that ancient humans possessed those modules? They don't. They describe, rather, modern behaviours, needs and knowledge and then assume that ancient humans can also be understood so. Far from using ancient behaviour to understand modern behaviour, evolutionary psychologists use modern behavioural categories to reconstruct our ancestors' minds.

In any case, even if we did know the behaviour patterns of early humans, this would not necessarily help us understand the roots of modern behaviour. This is because of the problems of using analogies as a scientific tool. Metaphor and analogy are very important to scientific reasoning because they allow us to view phenomena in new and distinct ways. Perhaps the most evocative and influential modern scientific metaphor is that of the 'selfish gene'. Richard Dawkins' memorable phrase illustrates the strengths of metaphor in science. It replaces the drab mathematics of population biology with a wonderfully illuminating picture of how natural selection might work. But it also illustrates the dangers of metaphoric thinking. All too often writers, including sometimes Dawkins himself, seem to forget they are dealing with a metaphor and argue as if genes actually were independent agents acting out their selfish desires.

In the case of the selfish gene its metaphoric nature is apparent to all, though some may forget it on occasion. In dealing with the relationship between modern behaviour and that of ancient humans, however, many Darwinists fail to grasp at all that they are dealing with an analogy, not a true material relationship.

Modern life is very different from Stone Age life. We partake in a myriad of activities, from going on holiday to wearing a condom, from watching TV to holding political demonstrations, that did not exist in the Pleistocene. How, then, do we translate from modern behaviour to ancient behaviour, and vice versa? By assuming that modern behaviours are in some way analogous to ancient behaviours. Cornering the futures market is like moving in for the kill in a hunt; following the party line at Westminster is akin to submitting to the authority of the alpha male; and so on. Too often, however, evolutionary psychologists fail to appreciate that these are simply imaginative analogies, of the kind that a poet or a novelist might use, and treat them instead as if there existed a real relationship between the two behaviours. 'It is poor science', Rosalind Arden pointed out in her recent debate in Prospect with Kingsley Browne, 'to pretend that stockbroking is like hunting and that staying at home with a small screamer is what women have evolved o cope with.' Indeed it is. But, unfortunately, much of evolutionary psychology rests on such assumptions.

The problem of analogical reasoning is particularly acute in making comparisons between the behaviours of humans and non-human animals. Unlike early hominids, animals are available for psychologists to observe and record their behaviour. This has made it very tempting to draw analogies between animal and human behaviour. Fighting between troops of chimps is like tribal warfare. A male orangutan's attack on a female is akin to rape. Anal intercourse among rats is homosexuality. In their book Demonic Males, Richard Wrangham and Dale Patterson, suggest that the relationship between different troops of spotted hyenas amount to 'foreign policy' and that chimps exhibit 'imperialistic' tendencies. EO Wilson has suggested that the behaviour of overcrowded rats is similar to that of concentration camp victims.

John Maynard Smith has pointed out that such anthropomorphism does little harm as long as our only interest is in animal behaviour. The problems, he observes, begin when we assume that animal 'rape' or 'war' can help illuminate human behaviours of the same name. This is exactly the assumption that evolutionary psychologists do make: that human and animal behaviours are more than simply analogous, but are governed by the same laws and forces. Or, to put it another way, they assume that since only natural selection can shape human behaviour, it is valid to compare human behaviours with those of animals with whom we are evolutionarily related.

Natural selection and divine intervention, however, are not the only explanations for the development of the human mind. There are material causes and motivations to human behaviour that are entirely absent from animal life. Unlike animals, humans are social and cultural beings, and human behaviour can only be understood within a social and cultural context. Of course, many animals are also social. But one of the fundamental mistakes of evolutionary psychology is to assume that the sociability of humans is of the same form as the sociality of non-human animals. This is not so. We may use the same word, but they describe two processes.

'Social' conduct in animals refers to any behaviour exhibited by a group that interacts with each other. It can range from zebras moving as a herd to minimise the effects of predators, to bees performing designated roles in a highly organised hive. One of the triumphs of modern Darwinism has been its explanation of how selfish genes give rise to social behaviour, including altruism.

Human sociability is entirely different. At its heart lies a skill that is uniquely human - language. Language allows humans to create a symbolic representation of the world, a picture of the world separate from the world itself. Without such a symbolic mode of expression, an animal may be able to react to the world, but it cannot, in any significant sense, think about it. It can have beliefs about the world, but it cannot know it has such beliefs. In other words, without language animals cannot possess self awareness. (There is a continuing debate as to whether chimpanzees are self-aware, and the extent to which they can manipulate symbols. This debate does not affect my argument here because, even should chimps possess both qualities, they do not make use of them during the normal course of their existence.)

Humans, on the other hand, because we possess language, do not simply have experiences, desires and needs, and react to them. We are also aware that we have them, that there is an 'I' which is the subject of these experiences, and which is a possessor of experiences, desires and needs. In other words humans are aware of themselves as agents, and of the world towards which their agency is directed.

Language and self-awareness transforms humanity's relationship to its evolutionary heritage. Take a basic biological response such as pain. All animals show pain. It is usually an automatic reflex and utterly recognisable - we are rarely in doubt when a horse, a dog or even a lizard is in pain. Yet the faculty of language transforms such a basic instinct within humans. One does not have to be a Baron Masoch to recognise that pain can sometimes be pleasurable, that sometimes we may seek pain, as part of sexual or other forms of gratification. In other words, as basic a physiological response as pain can be mediated through language and through social conventions, such that the human response to pain becomes different to that of other animals.

Similarly with anger. In Philip Roth's latest novel I Married a Communist, Lorraine, the niece of the central character Ira Ringold, refuses to salute the American flag at school in protest at the McCarthyite witch-hunt against her uncle. Years later, Lorraine's father, Murray, remembers how he pleaded with her. 'It's not being angry that's important, it's being angry about the right things. I told her, look at it from a Darwinian perspective. Anger is to make you effective. That's its survival function. That's why it's given to you. If it makes you ineffective, drop it like a hot potato.'

Murray is right: anger is a Darwinian response and has a survival function. But the very fact that he can recognise this, and understand also that there are other forms of anger available to human beings, reveals that here, too, the meaning of a simple Darwinian response has been transformed for humans through the existence of language and social conventions.

If basic emotions, such as pain and anger, can be given new meanings by being mediated through language, how much more is this true of more complex emotions such as guilt and shame? This is not to deny that emotions are evolved traits, many of which we share with our evolutionary relatives, or that they are universal to all cultures. But it is to suggest that even basic human emotions cannot understood in a purely naturalistic fashion, shaped as they are by human social development. And, if this is so, how is it possible that complex relationships such as power or love, whose very meanings are specifically human, can be understood in purely evolutionary, through analogies drawn from non-human animals, who possess neither language nor self-awareness?

Language and self-awareness transforms human life by making us conscious of ourselves as agents. Because we are conscious of ourselves as agents, we are aware of our capacity to transform the world around us. Human history is different from evolutionary history because it is Lamarckian not Darwinian in form. The nineteenth century French biologist Jean-Baptiste de Lamarck believed that changes that occur to an individual during its lifetime, in response to a 'felt need', can be inherited by its progeny. This, he claimed, was the basis of evolution. The long neck of a giraffe, for instance, evolved by the animal stretching its neck to browse on the foliage of trees, and its offspring being subsequently born with longer necks.

Darwin rejected this idea of the 'inheritance of acquired characteristics'. Instead he argued that random variation exists within a population of organisms, and that some of these variations will make the individual more successful in its struggle to survive and reproduce. If individuals are more successful in reproducing themselves, their characteristics will be passed on to the next generation.

Lamarckism describes a conscious or willed change, Darwinism an evolutionary process based on chance variation. We now know that natural evolution works in a Darwinian fashion. But development in human society is Lamarckian in form. Because humans possess the capacity for representing the world symbolically, and because we have created institutions which allow us to possess knowledge not simply as individuals but collectively as a society, so acquired habits and knowledge can be passed from generation to generation, transforming human life - and human nature - in the process. Humans are different because we are makers of our own history. In attempting to view human society in terms of natural selection, evolutionary psychologists conflate Darwinian and Lamarckian forms of evolution.

Human nature is dynamic, something that changes through history, a fact which evolutionary psychologists fail to grasp. Because they wish to understand human nature in a purely biological sense, so they have a static notion of what it means to be human. Human nature was constituted in the Stone Age and there it stopped. The most important aspect of what it means to be human - our sense of agency - is missing from Darwinian accounts.

I am not denying the influence of evolution upon human conduct. I am questioning the adequacy of evolutionary psychology as a means of understanding that influence. Humans certainly have an evolved psychology, but it cannot be understood in the same terms as the evolved psychologies of non-human animals. Nor can it be understood simply as an evolved psychology.

Take for instance, racism. It has become commonplace for evolutionary psychologists to view it as the product of an evolved trait - the innate propensity to categorise objects, and to view certain objects as 'natural kinds'. Without such a propensity, racism certainly could not occur - but nor could science and much else of human thinking. In any case, as many historians have pointed out, racism has not existed throughout history. It is a social form specific to modern society. And even within modern society, the nature and meaning of racism has developed and changed to a considerable degree. An evolutionary explanation of racism makes little more sense than an evolutionary explanation of racial difference.

Both the SSSM and evolutionary psychology have a common failing - an inadequate methodology with which to understand the relationship between our biological and social aspects. While the one denies Man's biological heritage, the other subsumes culture to biology. What both fail sufficiently to appreciate is that humans are subjects of their own history, not simply objects of either a biological or sociocultural process.

In understanding the human mind, therefore, we do not have to choose simply between natural selection and divine intervention as causative agents. Humans are also social creature, and social processes are no less material than physical ones. Implicitly, evolutionary psychologists understand this. For however much they may wish to see humans simply as Darwinian creatures they cannot deny that humans often act contrary to Darwinian principles. Thus, in his book Evolution in Mind, the psychologist Henry Plotkin opens his discussion on human culture by claiming that 'There is not much intellectual risk... in making the assumption that human culture is the product of human evolution.' A few pages later, though, he is forced to admit a problem with this view. If 'culture is the direct product of evolution', how is it possible, he asks, for culture to create forms that can 'adversely affect our biological fitness?' How, he wonders, can we understand celibacy or the risking of life and limb in distant wars? 'The only explanation', Plotkin believes, 'is that culture entails causal mechanisms that are somehow decoupled... from the causal mechanisms of our biological evolution'. Richard Dawkins similarly writes in The Selfish Gene that while 'We are built as gene machines... we have the power to turn against our creators.'

Steven Pinker has put this point most boldly of all. 'By Darwinian standards', he writes, 'I am a horrible mistake'. Why? Because he has chosen to remain childless. 'I am happy to be that way', he adds, 'and if my genes don’t like it they can go and jump in the lake'.

All this is a very stirring defence of human freedom. But how is it possible? If culture is 'the direct product of evolution', whence the capacity to 'decouple' the two? How do we possess 'the power to turn against our creators'? Presumably Pinker believes that his ability to tell his genes to go 'jump in the lake' must itself be an evolved trait. But how could such a trait survive? By definition it reduces biological fitness to zero. So how did it ever get passed on from one generation to the next? If a chimp or a horse told its genes to go take a jump, it would not survive very long in evolutionary terms. So how is it possible for humans to act like this, if we are governed simply by the same laws that hold sway over the rest of the animal kingdom?

From one perspective, Pinker's 'my genes can go jump' outburst sounds suspiciously like Sartre's 'Man is what he wills', an existential cry for freedom. From another perspective, the mysterious ability that Plotkin, Dawkins and Pinker all attribute to humans to turn against their genes smacks of Cartesian dualism. We seem, on the one hand, to be the product of our genetic heritage. But, on the other, we also seem to be animated by some mysterious non-natural force which turns us into genetic rebels.

One reason why evolutionary psychologists are so keen to stress the notion of free will is that they are wary of committing the 'naturalistic fallacy' - the belief that because something is natural it must be right. This belief underlay social Darwinism and racial science in the nineteenth century, and today's Darwinists are, understandably, keen to dissociate themselves from such a view. Pinker, therefore, proposes that ethics should be separate from the scientific study of behaviour. Science and ethics, he argues in How the Mind Works, are 'two self-contained systems played out among the same entities in the world'. The 'science game treats people as material objects, and its rules are the physical processes that cause behaviour through natural selection and neurophysiology.' The 'ethics game', on the other hand, 'treats people as equivalent, sentient, rational, free-willed agents, and its rules are the calculus that assigns moral value to behaviour through the behaviour's inherent nature or consequence'.

Ethics, presumably, are not some metaphysical entities, but an aspect of human behaviour. How then do they originate if not through 'natural selection and neurophysiology' which Pinker holds to be the basis of all other behaviours? Descartes, unable to comprehend how a mechanical science could explain the human mind, divided the human into a mechanical body and an unknowable soul. Pinker has done much the same - except that he has relabelled the soul as 'ethics'.

Only if we understand the social nature of humanity can we understand human freedom without resorting to such mysticism. It is absurd to suggest that we can tell our genes to go jump in the lake. But what we can do is to transform our evolutionary heritage through social development, through our capacity for agency and hence for making our history. It is in this process of transformation that human freedom lies. The unwillingness of evolutionary psychologists to understand humans as social beings, however, means that, far from providing a materialist account of human nature, evolutionary psychology is forced to follow its logic into the murky swamps of Sartrean existentialism or Cartesian dualism.

All of which brings us to the third premise of evolutionary psychology - the belief that there exists a conflict between our Stone Age genetic heritage and the modern world in which we live. 'Our brains', Steven Pinker writes, 'are not wired to cope with anonymous crowds, schooling, written language, governments, police, courts, armies, modern medicine, formal social institutions, high technology and other newcomers to the human experience.'

One can certainly imagine the distress that might be caused by mismatches between genetic capacity and environment. If some prankster transported a herd of elephants to the slopes of Mt Everest, or if a flock of penguins unaccountably found itself in the Sahara desert, the results might be disastrous. But we humans have not simply been transported to an alien environment. We have created that environment, through a long process of historical struggle and development. It seems bizarre to hold that the brain is 'wired up' to invent modernity but not to cope with it. If the brain is flexible enough to do the one, then why not the other?

This is, of course, is not a scientific question, but a philosophical one. The answer lies in how we choose to understand what it means to be human. In asserting a mismatch between genetic heritage and modern environment, evolutionary psychologists are adopting a particular philosophical stance about human nature and its limits. That is their prerogative. But they should not dress it up as science.
What the idea of a mismatch between genes and environment articulates is the sense of dislocation that many people feel today. The first person I recall making a sustained argument about the problems of such a mismatch was not an evolutionary psychologist but the Unabomber, perhaps the most potent expression of the modern sense of alienation. 'I attribute the social and psychological problems of modern society', he wrote in his manifesto, 'to the fact that society requires people to love under conditions radically different from those under which the human race evolved'.

At the height of the Cold War it was a common aphorism that humanity's technical prowess outstripped its moral advancement. With its 'mismatch' theory, evolutionary psychology has repackaged this sentiment for a more nihilistic age, when anxiety and unease arise, not from fear of a nuclear holocaust, but from feeling out of synch with much of the world.

If evolutionary psychology gives vent to our sense of dislocation, it also seems to provide a ticket to salvation, by creating a new myth about what it means to be human. 'People need a sacred narrative', EO Wilson argues in his book Consilience. 'They must have a sense of larger purpose, in one form or other, however intellectualised.' Such a sacred narrative, he believes, can be either a religion or a science. 'The true evolutionary epic', he writes, 'retold as poetry, is as intrinsically ennobling as any religious epic':

The continuity of the human line has been traced through a period of deep history a thousand times older than that conceived by the Western religions. Its study has brought new revelations of great moral importance. It has made us realise that Homo sapiens is far more than a congeries of tribes and races. We are a single gene pool from which individuals are drawn and into which they are dissolved the next generation, forever united as a species by heritage and a common future. Such are the conceptions, based on fact, from which new intimations of immortality can be drawn and a new mythos evolved.

Don't worry, be happy, we're all part of Nature's grand plan. We began with evolutionary psychology as an objective science of Man. We end with evolutionary theory as a new (or, perhaps, New Age) religion for mankind. The trouble with religion, whether drawn from the Book of God or the Book of Nature, is that it tends to make us blind to the facts.

The Darwinian approach has certainly provided some valuable insights about human nature. It has demonstrated the weaknesses of many social theories of human nature, and stressed the importance of understanding human beings in our biological context. One of the ironies of evolutionary psychology, however, is this: its adherents believe that their methodology allows them to study human behaviour with the same scientific objectivity and rigour as is generally applied to the study of animal behaviour. Yet the mishmash of wild speculation, banal generalisations, circular arguments, giddy leaps of logic and uncorroborated assertions which make up the bulk of the discipline would be treated with derision if applied to study of animal rather than human behaviour. The success of evolutionary psychology lies less in its scientific insights than in its ability to fill a gap left by discredited sociological explanations of human nature and to articulate a view of humanity that seems to make more sense in a pessimistic age.

And this leads us to a second irony. These criticisms of evolutionary psychology mirror those that Darwinians themselves, rightly, make about the bulk of twentieth century psychology, anthropology and social science. Darwinists have demonstrated convincingly that ideology as much as science motivated the SSSM – in particular a desire to challenge the then-dominant claims of social Darwinism and racial theory, and a belief that through social engineering humanity’s problems could be solved. Unfortunately, however, evolutionary psychology too seems to reflect the spirit of our times as much as it provides a scientific view of human nature.