BOOK REVIEW

Brain facts

The mental is the physical, and the think otherwise is obsolete, Steven Pinker argues in 'The Blank Slate'

By Daniel Smith, 12/22/2002

There invariably comes the time in any article about psychiatry at which a distinction is made between an illness located in the area roughly above and behind the eyes and an illness located in some other part of the body. The terms employed to make such a distinction, of course, are ''mental'' and ''physical.'' But there is a problem with this often-used binary formulation: It's obsolete. Who, this far into the neuroscientific revolution, three years after the close of the government-ordained Decade of the Brain, after such great leaps have been taken in imaging and treatment, could deny that the mental is physical?

The answer is: most people. The mental/physical dichotomy is still in use because it reflects a sadly persistent belief - that the workings of the brain are rooted not in biological processes but in some mystical force enshrined in the skull. This longstanding fallacy - what the psychologist Antonio Damasio has called ''Descartes' Error'' - is one of three persistent doctrines about the human mind that Steven Pinker has set out, in his characteristically ambitious new book, ''The Blank Slate: The Modern Denial of Human Nature,'' to explain the development of and, with luck, bury.

The book's argument can be described as follows: three associated philosophical doctrines as set forth by Descartes, Rousseau, and Locke - the Ghost in the Machine (a.k.a. ''Descartes' Error''), the Noble Savage (the idea that man is born good and corrupted by society), and the Blank Slate (the idea that the mind ''has no inherent structure and can be inscribed at will by society and ourselves''), respectively - have become ''the secular religion of modern intellectual life.'' However, a scientific revolution marked by the Human Genome Project and increased research into the human brain has begun to challenge these doctrines in ways that can no longer be ignored. This revolution has frightened those individuals who fear that discoveries about innate aspects of human nature will be used to justify inequality and weaken human responsibility and choice, and who believe that to endorse any concept of human nature is ''to endorse racism, sexism, war, greed, genocide, nihilism, reactionary politics, and neglect of children and the disadvantaged.''

The impetus behind Pinker's book appears to be that the anger with which discoveries of any innate qualities in human nature are often met spews most liberally from the mouths and pens of his fellow scientists. It comes as no surprise that Pinker is troubled by this phenomenon - for years detractors have unfairly accused him of being a ''biological determinist,'' which, in the scientific community, is roughly equivalent to being called a ''fatso'' in the kindergarten community. Nor does it come as a surprise that the scientist whom Pinker outs as one of the worst distorters of scientific research is the late Stephen Jay Gould, who died in May and with whom Pinker had been engaged in a feud.

But Pinker's personal involvement in the debate hardly diminishes his point that Gould and a cadre of ''radical scientists'' have dangerously mischaracterized scientific research for political means, as they did in their condemnation of the Harvard naturalist E. O. Wilson's ''Sociobiology,'' one chapter of which hypothesized that certain universal human characteristics were shaped by natural selection.

The discoveries being made of innate tendencies in human nature, Pinker writes, ''present[ed] intellectuals with a choice:''

''Cooler heads could have explained that the discoveries were irrelevant to the political ideals of equal opportunity and equal rights, which are moral doctrines on how we ought to treat people rather than scientific hypotheses about what people are like. [But] rather than detach the moral doctrines from the scientific ones many intellectuals, including some of the world's most famous scientists, made every effort to connect the two.''

The italics are mine; I have added them because the sentiment they highlight is the most crucial point in ''The Blank Slate.'' To rephrase that point: Facts about human nature need not dictate our morality. Injustice and cruelty are never justified, not even if we learn that injustice and cruelty are in part evolutionary instincts. We are humans, and as such are blessed with free will. And though we must scrutinize scientific research rigorously, turning away in horror at the facts about ourselves as a species is as self-defeating and even destructive as turning away in horror from the facts about ourselves individually. The fight for a separation of politics from science is an eminently sensible, logical, and ultimately humanistic task, and it took someone as brave as Pinker to dedicate himself to it.

If a quibble can be made with ''The Blank Slate'' it is that it is too long and even too thorough. Pinker's scrupulousness as a scientist and his ambitions as a writer lead him to scrutinize subjects as far afield as neural plasticity and Virginia Woolf, and in this case it distracts from the simplicity and accessibility of his message. A second quibble is with style. Pinker relies heavily on cliches. This tendency, I think, stems from a desire to be readable, but because Pinker's scientific expertise is language, it is a defect that is hard to overlook.

On the whole, however, these faults do not detract from so necessary a book, a book that in a more truthful intellectual climate - one open to the idea that any knowledge about ourselves can only enhance our ability to act well and compassionately - would not have had to be written. In this climate, however, we should be grateful that it was.

Daniel Smith is at work on a book about voice-hearing. He lives in New York City.

The Blank Slate: The Modern Denial of Human Nature

By Steven Pinker

Viking, 528 pps., $26.95

This story ran on page D8 of the Boston Globe on 12/22/2002.
© Copyright 2002 Globe Newspaper Company.