"The best book on human nature that I or anyone else will ever read." - Matt Ridley

The Blank Slate: The Modern Denial of Human Nature is a book by the linguist Steven Pinker, published in September 2002. It directly follows 1998's How the Mind Works, but it could arguably be said to be the prequel to that book. How the Mind Works was an epic attempt to explain the human mind using the methods of evolutionary psychology - the study of the cognitive processes taking place in the mind that ultimately have their basis in Darwinian natural selection. The book won him both admirers and detractors, but to appreciate the thesis at all - either approvingly or critically - the reader had to already accept the assumption that the mind is an adapted organ, an entity with an inherent nature, and not just something passively moulded by its environment ("Silly Putty" in Pinker's words). In other words, you have to reject what Pinker calls the Blank Slate theory - the idea that the human mind starts empty and is formed entirely by its experiences.

According to Pinker, this view has for a long time been the standard orthodoxy among Western intellectuals, and he aims to show that it is completely false. The mind is not the blank slate, or "white paper", of Locke's philosophy, but a complex, modular computational device with an innate structure - formed by natural selection - which it uses to navigate the world and learn from its experiences. In addition to the blank slate, Pinker challenges two other philosophical assumptions which, although independent of the blank slate (ot empiricism), are often found alongside it: the "Noble Savage" (romanticism) and what Ryle famously called the "Ghost in the Machine" (dualism). In other words, not only do we have a human nature, but we are not born morally untainted (Rousseau was wrong on that), nor do our minds consist in anything that is not ultimately grounded in the mechanics of the physical universe (Descartes was wrong on that). Pinker is not denying that environmental influences are crucial in shaping who we are (indeed one of his arguments is that an innate structure is necessary for any thinking device to learn at all): he is not saying that the slate is never written upon, but that it was not blank to begin with.

The evidence simply no longer supports it. Inheritance studies show a heritability of behaviour traits of around fifty percent. Human cultures, far from being infinitely variable as in the opinions of many well-known anthropologists, show remarkable similarities which attest to a universal human nature. Cognitive science - allied with common sense - is challenging the very possibility that a thinking device with no inherent nature would be any kind of thinking device at all. And tragically, the grim spectacle of genocide in the USSR and Cambodia has shown that political dogmas informed by a 100% environmental view of human behaviour can be as dangerous as those based on theories of the inherent superiority of some people or races over others.

An innate structure of the brain is required at the very least for technical feats such as visual perception, as computer programmers have discovered to their frustration when trying to build machines which can see. However the evidence also shows that behavioural and personality traits show a significant degree of heritability. In short, it is safe to say that the natural inclinations of humans have evolved in our social environment to favour behavioural traits which enhance the genetic fitness of ourselves and our close relatives. People tend to act selfishly - not in the sense of spitefulness, simply in the sense of favouring their own survival over that of others. They are also nepotistic and ethnocentric - relatives are given preferential treatment, and people are strongly inclined to prejudice against members of out-groups. Our tastes and intuitions have been formed by the savanna-based hunter-gatherer lifestyle in which we evolved. Sexual selection has left us with innate ideas of attractiveness in mates. And so on. We do not get every aspect of ourselves from the environment; not everything is a "social construction". Unfortunate as it may be, the problems of selfishness, malice and violence are not just etched into our brains by "culture" - they are manifestations of a human nature shaped by evolution. That does not mean to say they are inevitable - remember, genes are flexible - but they cannot be explained away as the result of social conditioning, nor can they be solved by naively nurturist social policies. Both selfishness and morality have their basis not in society but in evolution, as Matt Ridley has explored in The Origins of Virtue.

However the idea of the blank slate, which informs empiricist philosophy, behaviourist psychology, and most sociology, has become an unquestionable doctrine, in Pinker's view, helped greatly by the fact that it is seen as correct not just factually, but morally. Although it is at heart a simple, testable scientific hypothesis, it is treated more as dogma by various schools of thought. Most of its implications favour those on the political left, and those with a revolutionary bent - if there is no such thing as human nature, then there can be nothing inherent about the current, starkly unequal social order, and it should be replaceable by a fairer system. Left-wingers, and others interested in fairness and equality, are worried by the idea of human nature because it implies undesirable behaviour traits that cannot be changed, and innate differences between people leading to prejudice and inequality.

These feelings are so strong that any challenge whatsoever to the blank slate is liable to be denounced not only as factually incorrect but as bigoted, reactionary, fascist, or in some other way morally repugnant. (An extreme case of which Pinker is fond is that of the psychologist Paul Ekman, who was accused of racism and fascism for his assertion, both empirically sound and seemingly innocuous, that human facial expressions are largely identical among all cultures on Earth.) Pinker, a firm believer in social justice and equal rights, wishes to show that these fears are misplaced. Part Three of the book, "Human Nature with a Human Face", is devoted to allaying fears over four implications of a biological theory of human nature: inequality, imperfectibility, determinism, and nihilism. Pinker argues that fighting discrimination does not depend on the assumption that all people are born identical; that improving society does not require the denial of human nature; that the ultimately mechanical causes of our behaviour do not absolve people of responsibility for their actions; and that regarding humans as biological creatures grounded in physical reality does not make life "meaningless" in any relevant sense.

Toward the end of the book, he selects five areas of controversy ("Hot Buttons" as he calls them) and shows how they can be better understood by a way of thinking grounded not in the blank slate hypothesis, but in a biological theory of human nature. These topics are Politics, Violence, Gender, Children, and the Arts. In the chapter on politics, he notes that the idea of human nature has in the past aligned fairly closely with right-wing political views (e.g. Adam Smith's capitalism), but that in the future, scientific theories of human nature will increasingly cut across the left/right divide and, one hopes, escape the shortcomings of both. He mentions for example Peter Singer's book A Darwinian Left, and argues that an evolutionary understanding of human nature may well challenge the assumptions of absolute laissez-faire capitalism as it does those of socialism.

A similar mode of analysis is applied to the other four topics. In the chapter on gender he argues that the evidence for innate average differences in the abilities of men and women (which, incidentally, cut both ways) are irrelevant to the pursuit of gender equality. Not only are the differences slight and probabilistic, but the whole concept that people should not be discriminated against on the basis of gender - which of course Pinker accepts - does not fall apart just because men are slightly better at some things and women at others. In the chapter on the arts he traces the history of modernism and post-modernism and argues that, at least when pursued with no concession at all to traditional methods of creating art, they jar with an appreciation of art which is based in human nature. He offers this as an explanation of why the humanities are perceived to be in trouble - people are being put off by post-modernist nonsense.

Pinker's overall thesis for the book is not a novel one. This is a work of epic summary, rather than discovery: the arguments are drawn from a wide variety of traditions and thinkers. Rather, he recognises that the doctrine of the blank slate will not go away of its own accord, but must be actively challenged. In his view, it is an empirical hypothesis which has been found wanting, and stands in the way of a better understanding of people and a better informed practical approach to tackling the problems which blight the species just as much now as they did in the past. The Blank Slate is a summary of the way of thinking that is based in a scientific study of human nature - not just the evidence for it, but the insights it can give us into what we can and cannot, and should and should not do. It doesn't answer these questions, but it gives us a factually sound basis from which to start. Pinker hopes to show that the implications of the existence of a human nature are not just negative, nor are those of the blank slate theory entirely positive (for example B. F. Skinner's fearless view of a better society through relentless conditioning, grounded in blank slate, behaviourist assumptions).

Like all of Steven Pinker's books, The Blank Slate is engagingly, with a witty, familiar style, and many of his points illustrated by quotations of jokes (once again Woody Allen crops up throughout), cartoon strips culled from magazines, or references to popular culture (everyone from Earl Warren to Public Enemy). He truly is incapable of being boring, whether or not you agree with what he says. As someone who already agreed with the general thesis of the book and did not have many beliefs challenged by it, I can say that it was the most enjoyable book I have read for a long time; but the people who should really be reading it are those who want to see a more just society but wish to build on the reality of human nature as revealed by investigation, not grandiose assumptions about the perfectibility of man.

In the wrong hands, such a confident statement of this reality could have been an unnecessarily confrontational polemic giving pleasure to right-wingers and alienating the thinking Left. But because Pinker is not a right-winger, and takes the trouble to explain how his view of human nature does not attack the ideals of equality, and a better society for all, but rather shows how they might and might not be achievable, it does not fall into this trap. Indeed it is not really a very political book at all, and it certainly offers no policy prescriptions.

Unfortunately, from what I can tell, Pinker's challenge to various fashionable leftist orthodoxies has unfortunately been interpreted by some right-wingers as an outright attack on the Left from the Right. I don't think this is the case, particularly as the book notes some implications of human nature that challenge traditional conservative views, for example the idea that parents are completely responsible for whether their children grow up to behave morally. I hope that The Blank Slate, which is a truly outstanding book, will be read by many left-wing thinkers who believe in the assumption which the book challenges, but will be convinced that it is empirically false, and that it is not a necessary assumption for those who wish to change society for the better.

To read a more critical review of the book, try http://www.tnr.com/docprint.mhtml?i=20021125&s=blackburn112502