THE BLANK SLATE The modern denial of human nature by Steven Pinker

Steven Pinker is a man of encyclopedic knowledge and an incisive style of argument. His argument in The Blank Slate is that intellectual life in the West, and much of our social and political policy, was increasingly dominated through the twentieth century by a view of human nature that is fundamentally flawed; that this domination has been backed by something that amounts to academic terrorism (he does not put it quite so strongly); and that we would benefit substantially from a more realistic view. Pinker's exposition is thoroughly readable and of enviable clarity. His explanation of such a difficult technical matter as the analysis of variance and regression in twin studies, for example, would be very hard to better. He is not afraid of using strong language: "boo-word", "basket-case" and (for the technical term "psychopath") "evil"; in addition, parts of the book are delightfully funny.

The prevailing orthodoxy was once that "there is no such thing as human nature".

We are all like putty, infinitely malleable and capable of any degradation or improvement that can be brought about by the reaction between ourselves and our social institutions. In extreme cases, society is an organic entity directly, totally and solely responsible for the psychic make-up and behaviour of its individual members. Perhaps this is what Margaret Thatcher was thinking of when she remarked "There is no such thing as society."

Pinker traces the roots of this to a trinity of doctrines. The firstis the Ghost in the Machine, as originated by Descartes. This is the mind in a mind-body system, the conscious self, outside material causality and the site of free will.

The next tenet is the Blank Slate, proposed by Locke. The mind is conceived as a tabula rasa; it contains nothing at birth, no knowledge of course, but also no preferences, no tendencies, no instincts. Everything in it is written by experience.

The concept of the Blank Slate begat Rousseau's Noble Savage, full of peace and co-operation. This is the human in a natural state, uncorrupted by post-tribal society and therefore taught only communal values.

The Noble Savage is felled by comparative anthropology. Tribal societies have merits: they can probably bring pressure for cooperative behaviour -like not exceeding advisory speed limits -as can any village, because everybody can identify everybody else. But pre-state peoples are quite the reverse of pacific.

In the last century, the nation states killed an unacceptable number of their young men in repeated vicious wars; but that proportion of dead is minuscule against the annual deaths in battle of the men in "unspoilt" tribal societies.

Up to 60 per cent of the men in some tribes meet their end in this way. We think, rightly, that some of our cities are alarmingly violent. The murder rate among the hunter-gatherer !Kung, though, exceeds that of the US inner cities -we get the impression that the rates among hunter-gatherers are low only because the absolute numbers killed in their tiny populations are inevitably small.

Against the Blank Slate, Pinker marshals substantial evidence. The best, which he reviews extensively with considerable virtuosity, comes from experimental cognitive psychology, neuro-psychology and research on brain structure, and from psychopathology, both genetic and traumatic: the function of any part of the wiring is made plain when it stops working. Social practices which are universal across cultures, or which change in altered circumstances in a way that we would predict from evolutionary theory, are also strongly suggestive of some degree of hard-wiring. Oddly, one of the trinitarians' own arguments, that "there are no theory-free observations", is inimical to the Blank Slate.

Without some inbuilt theory, like a computer without its software, we could not get started. At birth we would recognize nothing, respond to nothing, learn nothing.