Assault on The Bell Curve

Inequality by Design, Cracking the Bell Curve Myth, Claude Fischer, Michael Hout, Martin Sanchez Jankowski, Samuel Lucas, Ann Swidler, Kim Voss, Princeton University Press, 1996, 318 pp.

A number of books now claim to discredit The Bell Curve, published in 1994 by Charles Murray and Richard Herrnstein. The most serious and non-hysterical critique is probably Inequality by Design, written by six members of the sociology department of the University of California at Berkeley. Within its limited sphere, it may be about as good an anti-hereditarian effort as can be made, and is worth reading for that reason alone. It is also an illuminating example of the thinking that still thrives on university campuses.

The authors of this book are offended by inequality — of any kind — and expect their readers to be, too. They see success and failure as almost exclusively the result of arbitrary social circumstances: “Research has shown that “nature’ determines neither the level of inequality in America nor which Americans in particular will be privileged or disprivileged; social conditions, and national policies do. Inequality is in that sense designed.”

This theme, set forth in the introduction, is repeated over and over: “It is not that low intelligence leads to inferior status; it is that inferior status leads to low intelligence test scores.” (italics in original) Heredity is not completely irrelevant, but it should be: “Being tall, slender, good-looking, healthy, male, and white helps in the race for success, and these traits are totally or partly determined genetically. But these traits matter to the degree that society makes them matter — determining how much, for example, good looks or white skin are rewarded. More important than these traits are the social milieux in which people grow up and live.” Anyone who does not understand this and who thinks that ability has something to do with success is “morally complacent.” Having thus shown their colors, the Berkeley professors spend their first 100 pages directly attacking The Bell Curve.

Much of The Bell Curve is an analysis of data from the National Longitudinal Study of Youth (NLSY), which has been tracking the lives of 12,000 young Americans since 1979. Although sociological studies usually pay no attention to intelligence, this group was given the Armed Forces Qualifications Test (AFQT), which yields results not unlike those of an IQ test. This way, The Bell Curve was able to determine the effect of intelligence on various social outcomes tracked by the study.

Intelligence was found to be a far better indicator than family background of whether an American is going to be poor, go to jail, have an illegitimate child, etc. The book also summarizes the evidence that intelligence is largely hereditary and debates the question of whether races differ in average intelligence because of genetic differences. (The authors of Inequality By Design provide an eight-page summary of the book for people who would rather read the critique than the object of the critique.)

Genes or Environment?

The Berkeley Six launch a variety of attacks. First, since the authors disbelieve in any unitary quality called intelligence, they deny that the AFQT measures it. They say it tests learning rather than intelligence, and to some degree it does — Drs. Herrnstein and Murray discuss the test’s nature and limitations. Inequality By Design nevertheless concedes that just as the SAT accurately predicts college grades, the AFQT accurately predicts performance in the military. This, though, is a vicious cycle: “The more institutions sort people by test scores, the better the test scores predict sorting. This predictive ability is then taken as a sign that the tests must be measuring intelligence . . .” For this to be true, it would require that the army, universities, and all other test users let the tests determine the kind of performance they value rather than the other way around. Instead of devising tests for the abilities they seek, they are shifting the abilities they value by selecting people who do well on tests.

The Berkeley Six also make the standard claim that if tests do measure intelligence it is only narrow, “classroom” intelligence, and “there is not much transfer between academic intelligence and everyday intelligence.” They also say that high test scores reflect nothing more than social class — the “privileged” do well because they grew up in fancy houses with books in them. If that were true, universities would presumably not bother with the SAT but would just ask applicants for a copy of their parents’ tax returns. Also, if the SAT is a test of social status, it is odd that whites from poor families should get higher scores than blacks from wealthy families.

The authors also claim that tests in general draw false distinctions between people who are all much the same: They “discover, magnify, and therefore solidify originally trivial differences.” The authors prefer the pass-fail system and recommend drivers’ tests as a model — the presence or absence of basic competence is all that matters, and finer gradations are meaningless and invidious. This seems to have been the thinking behind the Transit Authority employment test described in this month’s cover story. This approach would hardly help someone hire the best qualified, but at Berkeley there is presumably no such thing as the best — only the broadly qualified and the unqualified.

Probably because virtually everyone has a vivid, subjective sense of what intelligence is, the authors do not argue that there is no such thing. After explaining that IQ tests don’t measure it, they have a go at defining it: “Intelligence in the information-processing framework is mental self-management, and mental self-management involves selecting, adapting to, and shaping real-world environments. These intelligence skills can be taught and trained . . .” because “researchers are learning how to teach cognitive strategies explicitly.”

But if that is so, why don’t Berkeley public schools teach “intellectual self-management” along with reading and math? And if “researchers” are only now getting to the bottom of the arcane business of teaching “cognitive strategies” to children, how do high-status parents manage to do it without even trying? And if, as the authors repeatedly claim, intelligence can be taught, where are the school-room data to prove it? The authors do little to flesh out these claims.

Having demonstrated that intelligence can be taught but is not measured by IQ tests, the authors nevertheless go on to argue that even if the AFQT really does measure intelligence, the data in The Bell Curve still show that IQ is affected by environment, not genes. In what is actually the best and most carefully argued part of the book, the authors use the same regression analysis as in The Bell Curveto make their point.

The heart of their argument lies in The Bell Curve’s definition of socioeconomic status, or SES. Drs. Herrnstein and Murray determined the SES of a subject’s household from a combination of mother’s education, father’s education, household income, and parental occupation. As the graph on the next page shows, for people of average SES, AFQT scores predict the probability of poverty much more powerfully than does SES predict poverty for people with average AFQT scores.

The Berkeley professors think there is much more to SES. They added the number of siblings (children in big families get less adult attention), whether reared in a city or on a farm (they do not explain why this matters), and whether the subject lived with both parents until age 14 (having done so being a good thing). Adding these factors gives SES considerably more predictive power, but still not as much as the AFQT score.

(More specifically, when all the NLSY members with the average AFQT score are compared, those of the lowest SES, as defined by the authors, were about six times more likely to have become poor than those of the highest SES. However, when NLSY members of the average SES (as defined by the authors) were compared, those with the lowest AFQT scores were still 11 times more likely to be poor than those with the highest scores.)

The Bell Curve’s Findings

In order to get a combination of environmental factors that predict poverty as well as the AFQT does, the authors have to assemble a definition of SES that includes: father’s education, mother’s education, parental occupation, household income, number of siblings, urban or farm household, single-parent rearing, whether the subject was living in a depressed part of the country, and whether he went to a miserable school. When all these factors are combined and arrayed from very best to very worst they finally add up to enough “environment” to give predictions about poverty that are as good as a single score on a single standardized test.

To the extent they are willing to grant that AFQT scores may actually be indications of intelligence, the Berkeley Six argue that their array of social and environmental factors causes differences in intelligence rather than differences in intelligence producing different social outcomes. This is the well-worn environmentalist line. In the case of race differences, disbelievers in heredity hunt down whites living in the most degraded circumstances and report triumphantly that their IQs are as low as those of blacks.

The hereditarian reply is that these low IQs may be somewhat affected by environment but come mainly from low-IQ parents who, because they have low-IQs, give their children degraded environments. The authors note this argument but then claim, with no further elaboration, that they “have rejoinders to this charge.” They then cite a reference — a single unpublished talk given at a seminar.

This, then, is the heart of the book’s “refutation” of The Bell Curve: that an unfortunate family background, poor current circumstances, undesirable social outcomes, and low AFQT scores all go hand in hand, but that low test scores are strictly a consequence and not a cause. According to this analysis, rich parents can never have dim children nor can brilliance ever emerge from a slum. The book does not even attempt to deal with the evidence for the heritability and biological basis of intelligence: twin studies, adoption studies, inbreeding depression of test scores, reaction-time studies (it claims, without elaboration, that they have been discredited) brain-size research, and the extensive set of biological correlates to intelligence presented by Philippe Rushton. By ignoring the most direct evidence for the heritability of intelligence, and concentrating only on the correlation between low scores and failure in life, the book loses the argument by default.

The authors then round up the conventional, thread-bare arguments to explain the social failure of blacks and Hispanics. Unlike Asians, blacks are “involuntary minorities” brought to American in chains, and anyone who doesn’t understand how deep are the scars of slavery and Jim Crow is “historically and sociologically naive.” It is, of course, exquisitely irrelevant whether one’s great-great-great, great-great-grandparents came voluntarily or not. Whites born in America have as little choice about the matter as blacks. Moreover, Africa is full of people who would love to move the United States, for the same reasons that our “involuntary minority” shows no signs of going back. The Berkeley Six even call Hispanics an “involuntary minority” because of the Mexican-American War; they appear not to have noticed that most of them arrived long after 1848.

Slum-dwellers, we learn, are just as smart as business executives, and the authors go beyond the usual suggestion that bossing a drug gang takes as much brains as running Exxon: “Young men who “hustle’ a living, single mothers who balance limited funds and demanding children, [and] working men who juggle multiple low-paying jobs” are doing “the same kinds of sophisticated calculation required of professionals and executives.”

One problem blacks face is segregation. The authors do not believe that blacks might ever prefer to live with each other; even wealthy or middle-class blacks, we learn, cannot move to safe neighborhoods because whites won’t let them in. Moreover, “housing segregation means that minority renters and home purchasers pay more than whites for the same housing stock.” Of course, the opposite is true; the same house or apartment costs more if it comes with white neighbors. We learn that because segregation is now voluntary rather than legal, it may be even more hurtful to blacks, since whites are now expressing genuine preferences rather than submitting to law. Perhaps blacks would feel better if we brought back restrictive covenants.

Non-whites face other problems: “Numerous studies show that the economic advantages of staying in school are not nearly as great for blacks and Latinos as for whites.” In fact, if a non-white and a white graduate from the same school, with the same qualifications, the non-white often gets more job offers.

Finally, we learn that although conservatives may say anti-poverty programs, compensatory education, and affirmative action have failed to raise up blacks, the real problem is that they weren’t really tried. The notion that welfare encourages illegitimacy is hopelessly wrong; it is poverty that makes unwed women have babies.

Having disposed of the heritability of intelligence and the race/IQ question, the second half of the book is an explanation of how government could make America more equal — by taking money from people who have it and giving it to those who don’t. The authors grudgingly concede that there are already some policies that help the poor but complain, for example, that people actually have to have a taxable income before they can benefit from the earned income tax credit. They want handouts for the poor, centralized wage negotiations, and dream of a “system that encouraged employers to hire more, rather than fewer, workers.” This was tried in the Soviet Union. Only people who seem not to have noticed could write the following two sentences in sequence:

Many egalitarian policies stimulate and reward energy and initiative. If American law encouraged higher rates of unionization, more jobs would pay a decent wage.

There doesn’t seem to be much that government can’t do. After it has stimulated initiative through egalitarian policies, it can stimulate old people: “[C]ognitive skills keep changing over the life course and are changed by experience. Policy can intervene here by, for example, increasing older people’s opportunities for intellectual stimulation.”

For people not in the Berkeley sociology department, it is instructive to learn what these people think. Unfortunately, they are unusual only in their explicitness and in their willingness to carry egalitarian ideas to logical conclusions. In piecemeal fashion, ideas like theirs have seeped into popular consciousness and inform not only “liberalism” but much of what passes for political discourse.

Still, only people with doctorates in sociology are likely to write: “As for the structure of inequality, individuals’ native abilities are largely irrelevant.” How many business owners, athletes, musicians, authors, or even jail-birds and Bowery bums would agree with that? For some people, the more they study, the less they seem to know.