Discussion Group Report

"Intellectual life today is beset with a great divide," says Steven Pinker in his article, "The Blank Slate," in Discover, October 2002. "On one side is a militant denial of human nature, a conviction that the mind of a child is a blank slate that is subsequently inscribed by parents and society...At the same time there is a growing realization that human nature won't go away."

For much of the past century psychology has tried to explain all thought, feeling and behavior with a few simple mechanisms of learning by association. Social scientists have tried to explain all customs and social arrangements as a product of the surrounding culture. A long list of concepts that would seem natural to the human way of thinking--emotions, kinship, the sexes--are said to have been "invented' or "socially constructed." Behaviorist psychologists John B. Watson and B. F. Skinner simply banned notions of talent and temperament, together with all the other contents of mind, such as beliefs, desires and feelings. Watson boasted, "Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in. and I'll guarantee to take any one at random and train him to become any type of specialist I might select--doctor, lawyer, artist, merchant-chief, and yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors."

Yet anyone who has had more than one child, or been in a heterosexual relationship, or noticed that children learn language but house pets don't has recognized that people are born with different talents and temperaments. An acknowledgement that we humans are a species with a timeless and universal psychology pervades the writings of great political thinkers, and without it we cannot explain the recurring themes of literature, religion and myth. Moreover, the modern sciences of mind, brain, genes and evolution are showing that there is something to the commonsense idea of human nature. There must be complex innate mental faculties that enable human beings to create and learn culture.

The denial of human nature has not just corrupted the world of intellectuals but has harmed ordinary people. The theory that parents can mold their children like clay has inflicted child-rearing regimes on parents that are unnatural and sometimes cruel. It has increased the anguish of parents whose children haven't turned out as hoped. The belief that human tastes are reversible cultural preferences has led social planners to write off people's enjoyment of ornament, natural light and human scale and forced millions of people to live in drab cement boxes. And the conviction that humanity could be reshaped by massive social engineering projects has led to some of the greatest atrocities in history, Pinker says.

Cracks are appearing in the doctrine of the blank slate. As new disciplines such as cognitive science, neuroscience, evolutionary psychology and behavioral genetics flourished, it became clearer that thinking is a biological process, that the brain is not exempt from the laws of evolution, that sexes differ above the neck as well as below it, and that people are not psychological clones. There is a suggestion that the human mind evolved with a universal complex design. Anthropologists have returned to an ethnographic record that used to trumpet differences among cultures and have found an astonishingly detailed set of aptitudes and tastes that all cultures have in common. This shared way of thinking, feeling and living makes all of humanity look like a single tribe, which the anthropologist Donald Brown has called the universal people. Hundreds of traits, from romantic love to humorous insults, from poetry to food taboos, from exchange of goods to mourning the dead, can be found in every society ever documented.

Studies of the brain also show that the mind is not always a blank slate. The brain has a pervasive ability to change the strengths of its connections as the result of learning and experience--if it didn't we would all be permanent amnesiacs. But that does not mean that the structure of the brain is mostly a product of experience. Study of the brains of twins has shown that much of the variation in the amount of gray matter in the prefrontal lobes is genetically caused. . These variations are not just random differences in anatomy like fingerprints; they correlate significantly with differences in intelligence. People born with variations in the typical brain plan can vary in the way their minds work. A study of Einstein's brain showed that he had large, unusually shaped inferior parietal lobules, which participate in spatial reasoning and intuitions about numbers. Gay men are likely to have a relatively small nucleus in the anterior hypothalamus, a nucleus known to have a role in sex differences. Convicted murderers and other violent, antisocial people are likely to have a relatively small and inactive prefrontal cortex, the part of the brain that governs decision-making and inhibits impulses. These facts imply that differences in intelligence, scientific genius, sexual orientation and impulsive violence are not entirely learned.

The blank slate has often been widely embraced as a rationale for morality, but it is under assault from science. Yet just as the supposed foundations of morality shifted in the centuries following Galileo and Darwin, our own moral sensibilities will come to terms with the scientific findings, not just because facts are facts but because the moral credentials of the blank slate are just as spurious.

One of the fears associated with the idea of innate human endowment is the fear of inequality. Individuals, sexes, classes and races might differ innately in their talents and inclinations. If people are different, it would open the door to discrimination, oppression or eugenics. But none of this follows. A universal human nature does not imply that differences among groups are innate. Confucius could have been right when he wrote, "Men's natures are alike; it is their habits that carry them far apart."

Moreover, the case against bigotry is not a factual claim that people are biologically indistinguishable. Enlightened societies strive to ignore race, sex and ethnicity in hiring, admissions and criminal justice because the alternative is morally repugnant. Discriminating against people on the basis of race, sex or ethnicity would be unfair, penalizing them for traits over which they have no control.

Regardless of IQ or physical strength or any other trait that might vary among people, all human beings can be assumed to have certain traits in common. No one likes being enslaved. No one likes being humiliated. No one likes being treated unfairly.

A second fear of human nature comes from a reluctance to give up the age-old dream of the perfectibility of man. If we are forever saddled with fatal flaws and deadly sins, according to this fear, social reform would be a waste of time. But an antisocial desire is just one component among others. Some faculties may endow us with greed, lust or malice, but others may endow us with sympathy, foresight, self-respect, a desire for respect from others and an ability to learn from experience and history. Social progress can come from pitting some of these faculties against others.

Remarkably, although both Nazi and Marxist ideologies led to industrial-scale killing, their biological and psychological theories were opposites. Marxists had no use for the concept of race, were averse to the notion of genetic inheritance, and were hostile to the very idea of a human nature rooted in biology. "All history is nothing but a continuous transformation of human nature," wrote Mao.

But "the reminder that human nature is the source of our interests and needs as well as our flaws," states Pinker, "encourages us to examine claims about the mind objectively, without putting a moral thumb on either side of the scale."