The Blank Slate: The Modern Denial of Human Nature

by Steven Pinker

  (My own view, incidentally, is that in the case of the most discussed racial difference—the black-white IQ gap in the United States—the current evidence does not call for a genetic explanation. Thomas Sowell has documented that in most of the twentieth century and throughout the world, ethnic differences in IQ were the rule, not the exception.9 Members of minority groups who were out of the cultural mainstream commonly had average IQs that fell below that of the majority, including immigrants to the United States from southern and eastern Europe, the children of white mountaineers in the United States, children who grew up on canal boats in Britain, and Gaelic-speaking children in the Hebrides. The differences were at least as large as the current black-white gap but disappeared within a few generations. For many reasons, the experience of African Americans in the United States under slavery and segregation is not comparable to those of immigrants or rural isolates, and their transition to mainstream cultural patterns could easily take longer.)10

  And then there are the sexes. Unlike ethnic groups and races, in which any differences are biologically minor and haphazard, the two sexes differ in at least one way that is major and systematic: they have different reproductive organs. On evolutionary grounds one might expect men and women to differ somewhat in the neural systems that control how they use those organs—in their sexuality, parental instincts, and mating tactics. By the same logic, one would expect them not to differ as much in the neural systems that deal with the challenges both sexes face, such as those for general intelligence (as we will see in the chapter on gender).

  So COULD DISCOVERIES in biology turn out to justify racism and sexism? Absolutely not! The case against bigotry is not a factual claim that humans are biologically indistinguishable. It is a moral stance that condemns judging an individual according to the average traits of certain groups to which the individual belongs. Enlightened societies choose to ignore race, sex, and ethnicity in hiring, promotion, salary, school admissions, and the criminal justice system 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. It would perpetuate the injustices of the past, in which African Americans, women, and other groups were enslaved or oppressed. It would rend society into hostile factions and could escalate into horrific persecution. But none of these arguments against discrimination depends on whether groups of people are or are not genetically indistinguishable.

  Far from being conducive to discrimination, a conception of human nature is the reason we oppose it. Here is where the distinction between innate variation and innate universals is crucial. Regardless of IQ or physical strength or any other trait that can vary, all humans 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, that is, according to traits that the person cannot control. The revulsion we feel toward discrimination and slavery comes from a conviction that however much people vary on some traits, they do not vary on these. This conviction contrasts, by the way, with the supposedly progressive doctrine that people have no inherent concerns, which implies that they could be conditioned to enjoy servitude or degradation.

  The idea that political equality is a moral stance, not an empirical hypothesis, has been expressed by some of history’s most famous exponents of equality. The Declaration of Independence proclaims, “We hold these truths to be self-evident; that all men are created equal.” The author, Thomas Jefferson, made it clear that he was referring to an equality of rights, not a biological sameness. For example, in an 1813 letter to John Adams he wrote: “I agree with you that there is a natural aristocracy among men. The grounds of this are virtue and talents…. For experience proves, that the moral and physical qualities of man, whether good or evil, are transmissible in a certain degree from father to son.”11 (The fact that the Declaration originally was applied only to white men, and that Jefferson was far from an egalitarian in the conduct of his own life, does not change the argument. Jefferson defended political equality among white men—a novel idea in his time—even as he acknowledged innate differences among white men.) Similarly, Abraham Lincoln thought that the signers of the Declaration “did not mean to say all were equal in color, size, intellect, moral development or social capacity,” but only in respect to “certain inalienable rights.”12

  Some of the most influential contemporary thinkers about biology and human nature have drawn the same distinction. Ernst Mayr, one of the founders of the modern theory of evolution, wisely anticipated nearly four decades of debate when he wrote in 1963:

  Equality in spite of evident nonidentity is a somewhat sophisticated concept and requires a moral stature of which many individuals seem to be incapable. They rather deny human variability and equate equality with identity. Or they claim that the human species is exceptional in the organic world in that only morphological characters are controlled by genes and all other traits of the mind or character are due to “conditioning” or other nongenetic factors. Such authors conveniently ignore the results of twin studies and of the genetic analysis of nonmorphological traits in animals. An ideology based on such obviously wrong premises can only lead to disaster. Its championship of human equality is based on a claim of identity. As soon as it is proved that the latter does not exist, the support of equality is likewise lost.13

  Noam Chomsky made the same point in an article entitled “Psychology and Ideology.” Though he disagreed with Herrnstein’s argument about IQ (discussed in Chapter 6), he denied the popular charge that Herrnstein was a racist and distanced himself from fellow radical scientists who were denouncing the facts as dangerous:

  A correlation between race and IQ (were this shown to exist) entails no social consequences except in a racist society in which each individual is assigned to a racial category and dealt with not as an individual in his own right, but as a representative of this category. Herrnstein mentions a possible correlation between height and IQ. Of what social importance is that? None of course, since our society does not suffer under discrimination by height. We do not insist on assigning each adult to the category “below six feet in height” or “above six feet in height” when we ask what sort of education he should receive or where he should live or what work he should do. Rather, he is what he is, quite independent of the mean IQ of people of his height category. In a nonracist society, the category of race would be of no greater significance. The mean IQ of individuals of a certain racial background is irrelevant to the situation of a particular individual who is what he is….

  It is, incidentally, surprising to me that so many commentators should find it disturbing that IQ might be heritable, perhaps largely so. Would it also be disturbing to discover that relative height or musical talent or rank in running the one-hundred-yard dash is in part genetically determined? Why should one have preconceptions one way or another about these questions, and how do the answers to them, whatever they may be, relate either to serious scientific issues (in the present state of our knowledge) or to social practice in a decent society?14

  Some readers may not be reassured by this lofty stance. If all ethnic groups and both sexes were identical in all talents, then discrimination would simply be self-defeating, and people would abandon it as soon as the facts were known. But if they are not identical, it would be rational to take those differences into account. After all, according to Bayes’ theorem a decision maker who needs to make a prediction (such as whether a person will succeed in a profession) should factor in the prior probability, such as the base rate of success for people in that group. If races or sexes are different on average, racial profiling or gender stereotyping would be actuarially sound, and it would be naïve to expect information about race and sex not to be used for prejudicial ends. So a policy to treat people as individuals seems like a thin reed on which to hang any hope of reducing discrimination.

  An immediate reply to this worry is that the danger ar
ises whether the differences between groups are genetic or environmental in origin. An average is an average, and an actuarial decision maker should care only about what it is, not what caused it.

  Moreover, the fact that discrimination can be economically rational would be truly dangerous only if our policies favored ruthless economic optimization regardless of all other costs. But in fact we have many policies that allow moral principles to trump economic efficiency. For example, it is illegal to sell your vote, sell your organs, or sell your children, even though an economist could argue that any voluntary exchange leaves both parties better off. These decisions come naturally in modern democracies, and we can just as resolutely choose public policies and private mores that disallow race and gender prejudice.15

  Moral and legal proscriptions are not the only way to reduce discrimination in the face of possible group differences. The more information we have about the qualifications of an individual, the less impact a race-wide or sex-wide average would have in any statistical decision concerning that person. The best cure for discrimination, then, is more accurate and more extensive testing of mental abilities, because it would provide so much predictive information about an individual that no one would be tempted to factor in race or gender. (This, however, is an idea with no political future.)

  Discrimination—in the sense of using a statistically predictive trait of an individual’s group to make a decision about the individual—is not always immoral, or at least we don’t always treat it as immoral. To predict someone’s behavior perfectly we would need an X-ray machine for the soul. Even predicting someone’s behavior with the tools we do have—such as tests, interviews, background checks, and recommendations—would require unlimited resources if we were to use them to the fullest. Decisions that have to be made with finite time and resources, and which have high costs for certain kinds of errors, must use some trait as a basis for judging a person. And that necessarily judges the person according to a stereotype.

  In some cases the overlap between two groups is so small that we feel comfortable discriminating against one of the groups absolutely. For example, no one objects to keeping chimpanzees out of our schools, even though it is conceivable that if we tested every chimp on the planet we might find one that could learn to read and write. We apply a speciesist stereotype that chimps cannot profit from a human education, figuring that the odds of finding an exception do not outweigh the costs of examining every last one.

  In more realistic circumstances we have to decide on a case-by-case basis whether the discrimination is justifiable. Denying driving and voting rights to young teenagers is a form of age discrimination that is unfair to responsible teens. But we are not willing to pay either the financial costs of developing a test for psychological maturity or the moral costs of classification errors, such as teens wrapping their cars around trees. Almost everyone is appalled by racial profiling—pulling over motorists for “driving while black.” But after the 2001 terrorist attacks on the World Trade Center and the Pentagon, about half of Americans polled said they were not opposed to ethnic profiling—scrutinizing passengers for “flying while Arab.”16 People who distinguish the two must reason that the benefits of catching a marijuana dealer do not outweigh the harm done to innocent black drivers, but the benefits of stopping a suicide hijacker do outweigh the harm done to innocent Arab passengers. Cost-benefit analyses are also sometimes used to justify racial preferences: the benefits of racially diverse workplaces and campuses are thought to outweigh the costs of discriminating against whites.

  The possibility that men and women are not the same in all respects also presents policymakers with choices. It would be reprehensible for a bank to hire a man over a woman as a manager for the reason that he is less likely to quit after having a child. Would it also be reprehensible for a couple to hire a woman over a man as a nanny for their daughter because she is less likely to sexually abuse the child? Most people believe that the punishment for a given crime should be the same regardless of who commits it. But knowing the typical sexual emotions of the two sexes, should we apply the same punishment to a man who seduces a sixteen-year-old girl and to a woman who seduces a sixteen-year-old boy?

  These are some of the issues that face the people of a democracy in deciding what to do about discrimination. The point is not that group differences may never be used as a basis for discrimination. The point is that they do not have to be used that way, and sometimes we can decide on moral grounds that they must not be used that way.

  THE BLANK SLATE, then, is not necessary to combat racism and sexism. Nor is it necessary to combat Social Darwinism, the belief that the rich and the poor deserve their status and so we must abandon any principle of economic justice in favor of extreme laissez-faire policies.

  Because of a fear of Social Darwinism, the idea that class has anything to do with genes is treated by modern intellectuals like plutonium, even though it is hard to imagine how it could not be true in part. To adapt an example from the philosopher Robert Nozick, suppose a million people are willing to pay ten dollars to hear Pavarotti sing and are unwilling to pay ten dollars to hear me sing, in part because of genetic differences between us. Pavarotti will be ten million dollars richer and will live in an economic stratum that my genes keep me out of, even in a society that is totally fair.17 It is a brute fact that greater rewards will go to people with greater inborn talent if other people are willing to pay more for the fruits of those talents. The only way that cannot happen is if people are locked into arbitrary castes, if all economic transactions are controlled by the state, or if there is no such thing as inborn talent because we are blank slates.

  A surprising number of intellectuals, particularly on the left, do deny that there is such a thing as inborn talent, especially intelligence. Stephen Jay Gould’s 1981 bestseller The Mismeasure of Man was written to debunk “the abstraction of intelligence as a single entity, its location within the brain, its quantification as one number for each individual, and the use of these numbers to rank people in a single series of worthiness, invariably to find that oppressed and disadvantaged groups—races, classes, or sexes—are innately inferior and deserve their status.”18 The philosopher Hilary Putnam argued that the concept of intelligence is part of a social theory called “elitism” that is specific to capitalist societies:

  Under a less competitive form of social organization, the theory of elitism might well be replaced by a different theory—the theory of egalitarianism. This theory might say that ordinary people can do anything that is in their interest and do it well when (1) they are highly motivated, and (2) they work collectively.19

  In other words, any of us could become a Richard Feynman or a Tiger Woods if only we were highly enough motivated and worked collectively.

  I find it truly surreal to read academics denying the existence of intelligence. Academics are obsessed with intelligence. They discuss it endlessly in considering student admissions, in hiring faculty and staff, and especially in their gossip about one another. Nor can citizens or policymakers ignore the concept, regardless of their politics. People who say that IQ is meaningless will quickly invoke it when the discussion turns to executing a murderer with an IQ of 64, removing lead paint that lowers a child’s IQ by five points, or the presidential qualifications of George W. Bush. In any case, there is now ample evidence that intelligence is a stable property of an individual, that it can be linked to features of the brain (including overall size, amount of gray matter in the frontal lobes, speed of neural conduction, and metabolism of cerebral glucose), that it is partly heritable among individuals, and that it predicts some of the variation in life outcomes such as income and social status.20

  The existence of inborn talents, however, does not call for Social Darwinism. The anxiety that one must lead to the other is based on two fallacies. The first is an all-or-none mentality that often infects discussions of the social implications of genetics. The likelihood that inborn differences are one contributor to social
status does not mean that it is the only contributor. The other ones include sheer luck, inherited wealth, race and class prejudice, unequal opportunity (such as in schooling and connections), and cultural capital: habits and values that promote economic success. Acknowledging that talent matters doesn’t mean that prejudice and unequal opportunity do not matter.

  But more important, even if inherited talents can lead to socioeconomic success, it doesn’t mean that the success is deserved in a moral sense. Social Darwinism is based on Spencer’s assumption that we can look to evolution to discover what is right—that “good” can be boiled down to “evolutionarily successful.” This lives in infamy as a reference case for the “naturalistic fallacy”: the belief that what happens in nature is good. (Spencer also confused people’s social success—their wealth, power, and status—with their evolutionary success, the number of their viable descendants.) The naturalistic fallacy was named by the moral philosopher G. E. Moore in his 1903 Principia Ethica, the book that killed Spencer’s ethics.21 Moore applied “Hume’s Guillotine,” the argument that no matter how convincingly you show that something is true, it never follows logically that it ought to be true. Moore noted that it is sensible to ask, “This conduct is more evolutionarily successful, but is it good?” The mere fact that the question makes sense shows that evolutionary success and goodness are not the same thing.