A Brief Analysis of 'The Bell Curve'

Julian Paul Keenan
Department of Psychology
The University at Albany
112 Social Science
Albany, New York, 12222


The Bell Curve (Hernstein & Murray, 1994) has continued to elicit sharp reaction and criticism. The messengers and the message have both been challenged on empirical and moral grounds and the debate continues to rage on. This article will attempt to briefly review some of the challenges, while admitting that a full analysis of the subject would require another volume, or series of books, which have begun to emerge in response to The Bell Curve. The issue of race is discussed, as are the possible influences of funding and the danger of such motivation in public policy. The size of the heritable effect of IQ is discussed, as is the effect of the environment.


The Bell Curve (Hernstein & Murray, 1994) has provoked some of the sharpest debates and attacks in this decade (Jacoby & Glauberman, 1995). In subtle and not so subtle ways, the authors of The Bell Curve have used intelligence research to substantiate claims that African- Americans are genetically inferior in intellectual abilities and capabilities. While these claims are not new (see Osbourne, Noble, & Weyle, 1978), The Bell Curve has touched upon issues that are not only sensitive to the majority of persons in this country (Betancourt & Lopez, 1993), but also basic to the establishment of governmental public policy.

Perhaps the scientific community would have remained silent if social policy was not implicated in The Bell Curve. However, a history of agenda setting and data manipulation, particularly in this area, is not new. Consider the social agenda of Gustave Le Bon, a student of Paul Broca's. Arguing that females are inevitably less intelligent because of their smaller brains, he writes in 1879:

All psychologists who have studied the intelligence of women, as well as poets and novelists, recognize today that they represent the most inferior form of human evolution and that they are closer to children and savages than to an adult civilized man. They excel in fickleness, inconsistency, absence of thought and logic, and incapacity to reason. Without doubt there exist some distinguished women, very superior to the average man, but they are as exceptional as the birth of any monstrosity, as, for example, a gorilla with two heads; consequently, we may neglect them entirely (pp. 359, Kriszner & Mandell, 1996).

As will be described in the following review, Le Bon also prescribes the appropriate social agenda based on his findings, "A desire to give them (women) the same education, and, as a consequence, to propose the same goals for them, is a dangerous chimera…" (pp. 359, Kriszner & Mandell, 1996).

It is possible that the issue of intelligence and groups is one of both science and policy and that an evaluation of one can not be conducted without the other. Even researchers that argue against group differences in IQ advocate social agendas (see Angoff, 1988). Finally, while social policy is the danger of intellegince research, it should also be noted that the dependent measure, namely IQ, is assumed throughout The Bell Curve to measure the construct of intelligence. While this argument is beyond the scope of this paper, one should obviously be cautious of the dubious assumption (see Loehlin, Lindzey, & Spuhler, 1975).

The topics covered in The Bell Curve do not, by themselves, necessitate controversy. If given fair treatment the conclusions reached by any author reviewing the material should not be in themselves controversial (Jacoby & Glauberman, 1995; Table 1). However, it is the treatment of these subjects that aroused researchers' interests in the claims of the book. The issue may be as follows. The material that is reported early in the text appears to reflect the motivations for the later chapters. Material that is selected for review in the early chapters is not a complete analysis, but a strategy that enables the authors to prove, for example, that affirmative action is not beneficial for this country.

Table 1. The Table of Contents of "The Bell Curve"

Part I. The Emergence of a Cognitive Elite
  1. 1 Cognitive Class and Education, 1900-1990
  2. 2 Cognitive Partitioning by Occupation
  3. 3 The Economic Pressure to Partition
  4. 4 Steeper Ladders, Narrower Gates
Part II. Cognitive Classes and Social Behavior
  1. 5 Poverty
  2. 6 Schooling
  3. 7 Unemployment, Idleness, and injury
  4. 8 Family Matters
  5. 9 Welfare Dependency
  6. 10 Parenting
  7. 11 Crime
  8. 12 Civility and Citizenship
Part III. The National Context
  1. 13 Ethnic Differences in Cognitive Ability
  2. 14 Ethnic Inequalities in Relation to IQ
  3. 15 The Demography of Intelligence
  4. 16 Social Behavior and the Prevalence of Low Cognitive Ability
Part IV. Living Together
  1. 17 Raising Cognitive Ability
  2. 16 The Leveling of American Education
  3. 19 Affirmative Action in Higher Education
  4. 20 Affirmative Action in the Workplace
  5. 21 The Way We Are Headed
  6. 22 A Place for Everyone

The writing tone of the early chapters is perhaps best described as aggressive. For example, the authors claim early in the second chapter:

IQ becomes more important as the job gets intellectually tougher. To be able to dig a ditch, you need a strong back, but not necessarily a high IQ score. To be a master carpenter, you need some higher degree of intelligence along with skill with your hands. To be a first- rate lawyer, you had better come from the upper end of the cognitive distribution. The same may be said for a handful of other occupations, such as accountants, engineers and architects, college teachers, dentists and physicians, mathematicians, and scientists (pp. 51).

Either by omission, or inclusion, the claims are in the least inflammatory and not backed by research. Consider the following paragraph from the third chapter:

Almost anyone can become a ditch digger (if he has a strong enough back); anyone can become cabinetmakers (if they have good enough motor skills), but only few people from a fairly narrow range of cognitive ability can become lawyers. If lawyering pays more than cabinet making, what happens as the number of Lawyering jobs increase, as it has in America? (pp. 54).

The authors continue in the next chapter:

These possibilities all bear on a crucial issue: How much good would it do to encourage education for the people earning low wages? If somehow (government can cajole or entice youths to stay in school for a few extra years, will their economic disadvantage in the new labor market go away? We doubt it. Their disadvantage might be diminished, but only modestly. There is reason to think that the job market has been warding not just education but intelligence (pp. 96).

The authors' citations include one reference to themselves and three others in the early 1970's. This aside, it appears that the controversy of the book may not be confined to the chapters that are reserved exclusively for race and racial agendas. The authors also include the following statement in one of the later chapters:

We want to call people whatever they prefer to be called, including their preferences for ethnic labels. As we write, however, there are no hard-and fast rules, People from Latin America wish to be known according to their national origin: Cuban-American, Mexican-American, Puerto Rican, and so forth. Hispanic is still the US government's official label, but Latino has gained favor in recent years. We use Latino. Opting for common usage and simplicity, we usually use black instead of African-American and white (which always refers to non-Latino whites) instead of European-American or Anglo. Americans of Asian descent are called Asian when the context leaves no possibility of confusion with Asians living in Asia. We shift to the hyphenated versions for everyone when it would avoid such confusions or when, for stylistic reasons, the hyphenated versions seem appropriate (pp. 271).

Contrary to their own claims, the authors seem to settle on what they prefer or as they state, what is simplest. While it is not the tone or the writing style that inflamed many scientists, it should be noted as a compelling feature. The authors' appear to bream with confidence and allow themselves terminology that can be deemed politically incorrect, and nearly indecent (Jacoby & Glauberman, 1995). While it is not the role of science to be correct or political, in the realm of intelligence and race research it is possible that sensitivity may allow the reader to approach the data with an open mind. This idea appears to elude the authors', a consequently the stage is set for an 'us versus them' mentality (Jacoby & Glauberman, 1995; see below).

A Matter of Race

In an exploration of racial differences in the context of intelligence, it is necessary to ascertain what is meant by race. Hardly an inbred stock of laboratory animals, the question of determines racial boundaries and categories is quite important. Surprisingly, for a book that dedicates much of its discussion to racial differences, only one paragraph is given on the operational definition of race:

We frequently use the word ethnic rather than race, because race is such a difficult concept to employ in the American context What does it mean to be "black" in America, in racial terms, when the word black (or African-American) can be used for people whose ancestry is more European than African? How are we to classify a person whose parents hail from Panama but whose ancestry is predominantly African? Is he a Latino? A black? The rule we follow here is to classify people according to the way they classify themselves. The studies of "blacks" or "Latinos" or "Asians" who live in America generally denote people who say they are black, Latino, or Asian--no more, no less (pp. 271).

This classification scheme is inherently dangerous and it certainly does not provide a convincingly homogeneous group. In fact, the problems of identifying genetically discrete populations are such that many researchers disagree as to how many races there are and many argue whether the concept is useful at all (Gossett, 1963). Allen and Adams (1992) called for the abandonment of race or the development of a scientific definition. Betancourt & Lopez (1993) cautioned against race as a variable.

In review article, Yee, et al. (1993) report on the conclusions reached by Zuckerman (1990): By reanalyzing many psychological studies reporting race differences, as on temperament and basic personality traits, Zuckerman demonstrated the dubiousness of results obtained through race premises. He found much more variation within groups designated, and, like many other species, humans showed considerable geographical variation in morphology (p. 1134).

The problem of classifying race is not simple. Perhaps this idea is best expressed as Phillip Ruston, another proponent of The Bell Curve has proposed the following grouping scheme: Imagine that a team of extra- terrestrial biologists arrive on earth to study humans. Would they not quickly observe that like many other species, humans showed considerable, geographical variation in morphology? Surely three major geographical populations of 'races' would be identified immediately... (p. 29). This system provides a classification scheme based upon observational differences. It seems obvious that there is a problem with this classification scheme. After an exhaustive explanation, Montagu (1975) concluded:

...the distinction between races is often quite blurred. This is mainly the result of interbreeding between races at their boundaries, and of the mixing effect of large migrations. Even in the United States, where marriage between American blacks and whites is still quite rare, it is estimated that up to 30% of the genes of the average black American from the northern states can be traced to white ancestry. This, of course, represents the cumulative effect of a number of generations during each of which a small amount of interbreeding took place. The American blacks are now clearly a new population genetically, which has been formed from a mixture of black Africans and white Americans. The Jews provide another example of the blending of racial distinctions. They are all presumably derived from one population, or at most a few closely related populations, of biblical times. Gene frequency studies, however, show that now Jewish populations in different parts of the world tend to resemble their surrounding populations at least as much, if not more, than they do each other. Such genetic studies, when combined with historical information, and sociological ideas of race and culture, can be very useful in understanding the origin of modern populations (p. 260).

Again, this is only a hint of the debate brought forth by The Bell Curve, and many pertinent discussions are admittedly left out of the discussion (see Allen & Adams, 1992; Betancourt & Lopez, 1993; Yee, et al., 1993 for review). However, if there is no clear definition of race, or there is such a definition and there are no homogenous members of race in a population, it seems difficult to trust the claims of Herrnstein and Murray. Self identification of race and IQ differences between races may actually support those who argue for environmental influences on IQ. We have a unique situation in which the environment treats phenotypes differently as opposed to different genotypes influencing phenotypes.

An early study that addressed the mixed racial backgrounds was done by Garth (1931). He found that the difference between IQ scores correlated (.42) with the difference in race in parents between white and Native American. Mixed blood Native Americans (e.g., those with Euro- ancestry as well as Native American lineage) tended to have higher IQs than pure bloods (e.g., no Euro- ancestry). Testing 765 subjects, it was found that those subjects with one- quarter blood (one Native American grandparent) had on average, IQs around 77. Those with three- quarter blood (three Native American grandparents) had IQ scores around 74. Unfortunately, environment was not held constant in this study and those subjects who were 'more white' also tended to live in areas that were more western (e.g., a more traditional Euro- environment) and with more traditional western homes. Another early researcher was Tasner. Using a similar design, he found that mixed groups (Caucasian and African- Americans) had higher IQ scores than those African- Americans without Caucasian parents (1939, 1962). However, when Tasner examined the African- American group more closely, he found that the half African- American group scored lower than the three- quarters African American group. There is controversy over the assertion that the environments between the groups was equal.

Osbonre and Suddick (1971, as reported in Loehlin, 1975) used a somewhat different method to disentangle the possible genetic effects of race on IQ scores. The authors attempted to use 16 blood- group genes known to have come from European ancestors. Testing two samples the authors found that the correlation over the 16 genes and IQ scores was not highly positive as would have been predicted if European genes in blacks increased IQ scores. In fact, the correlations were -.38 and +.01. Because the results were not significant, the authors were unable to conclude that European genes lower IQ scores. The result does show that when gene sets are factored into the equation, the differences that should exist according to Herrnstein and Murray do not. Loehlin reports on Eyeferth's (1961) study that found that in children born in Germany after World War II, there was tendency for the children who had approximately 40% of their genes from African origin to have lower IQ scores than children of pure European descent. Willerman, Naylor, & Myrianthopoulus (1971, 1974) found a significant interaction between race of mother and IQ score of the child as a function of the child's age.

Table 2. From Loehlin (1975) 1

Witty and Jenkins (1936) showed similar results when they examined the differences in IQ scores among African- Americans. It can be seen that the highest occurring percent of gifted children in the sample was the 'More Negro than white' sample, while the lowest percent of gifted children came from the 'More white than Negro' group.

Environment and Genetics

Obviously the lack of an appropriate operational definition for race greatly undermines the whole of Herrnstein and Murray's position. Even when controlled for, the results typically run counter as to what would have been expected by supporters of The Bell Curve. This is not to say that there are no genetic influences on IQ scores. The argument only implies that African- Americans do not appear to have a gene or gene set that is responsible for their lower IQ scores.

Table 3. Plomin (1988) 1

Plomin (1988) convincingly argues for a genetic component for IQ scores. Table Three demonstrates the obvious genetic correlations between related and non- related children. These data are indicative of an entire literature that points towards a genetic influence in the order of 50% of the variance. However, even in this paper, Plomin points out that environment plays a significant role as well. Some researchers claim that the effect of the environment can alter scores 30 points (two standard deviations; Kline, 1991). A full analysis of the literature is not possible here, but it should be acknowledged that there are influences of both the environment and genetics on IQ scores.


The most interesting aspect of The Bell Curve lies in its motivation. Organizations such as the Bradley Foundation and the Pioneer fund surround both authors and the connection to the groups is certainly interesting, to say the least.

The Bell Curve cites a journal called the Mankind Quarterly five times throughout the course of the book. Furthermore, seventeen of the researchers cited from The Bell Curve have contributed to The Mankind Quarterly . Ten of the citations in the book refer to editors or former editors of the journal. Mankind Quarterly was founded by Robert Gayle, a notorious racist. He testified for the defense of five members of the British Racial Preservation Society, and he is quoted as saying during the trial that blacks are "worthless". Other editors of the journal provided testimony for the defense in Brown vs. Board of Education, and others are members eugenics movements. In fact, one member of the editorial board took part in the race science under Hitler during Nazi Germany's rise to power.

The journal is now run by Roger Pearson and it is supported by the Pioneer Fund. The fund was established in 1937 by a Nazi Germany sympathizer and a strong advocate of apartheid; the fund's first president was a leader in a eugenicist movement that attempted to ban immigrants. In fact, the initial charter of the Pioneer Fund was set up on the agenda of race betterment, with special reference to the people of the United States (see Jacoby & Glauberman, 1995). The connection between Herrnstein and Murray with the organization is somewhat substantial. As well as citing the authors who have published in the Mankind Quarterly, The Bell Curve makes reference to thirteen scholars who have received funding (over $4 million dollars) from the Pioneer Fund.

Arthur Jensen, cited twenty- three times, is one such recipient of Pioneer funds. He has alone received over 1.1 million dollars from the fund and it is appears that his motivation for research is possible racially motivated (Yee, 1993). Another infamous connection is R. Travis Osbourne, author of Human Variation (1978). The book appears to make certain racist conclusions based on minimal research (see pg. 137- 167). Richard Lynn, another Pioneer recipient ($325,000) is cited twenty- four times in The Bell Curve. He has reported (as cited in The Bell Curve) that African blacks have lower IQ scores than American blacks, and that it is likely that the increase in IQ scores by American blacks is due to inter- breeding (see pg. 125- 139 in Jacoby & Glauterman, 1995).

Levin, another Pioneer recipient whose work is also cited heavily in The Bell Curve is quoted in The Bell Curve Debate:

I'm interested in innocence for whites, and the genetic hypothesis is evidence for the defense, it undercuts affirmative action, the basis for which is the great black claim on the American consciousness that "We're down, and you owe us for what you did to us with slavery and Jim Crow." Race differences show whites aren't at fault for blacks being down, and making whites pay for something they're not responsible for is a terrible injustice. Eliminating affirmative action is the first step. Next--please, yes, if only--eliminate the Civil Rights Act (pp. 165).

Further in to the interview in which the article is based upon, Levin contends that: Let's go back to 1954 and tell a story. Blacks are not doing well, and everyone said, "Well, if we just had equal education, that'll change, just like it did for Italians, Jews, the Irish." Instead blacks got more antisocial, and whites fled. Now it's 1994 and [it's] even worse. The reason is two basic and unalterable black characteristics: less intelligence and greater proneness to violence... It's a horrible, sadistic thing that Washington tells whites, "You have to send your kids to school with blacks so they can beat them up... Don't white kids have any rights? It's terrible to make them go to school with blacks, who are intellectually inferior and misbehave in class. You know, my son is transferring to [a very selective public high school] in the fall. They've got a special program for blacks. I just hope they leave him alone... Blacks just have fewer inhibitions, a greater readiness to express anger, an impulsiveness. It fuels this incredible idea that you see something you want and shoot somebody to get it. What do they do that for? Because the alternative--to work and save-is not psychologically available (pp. 166).

Final Impressions

The Bell Curve perhaps achieved its purpose by sparking academic debate. The subsequent books, replies, articles and popular press coverage that ensued after the release of The Bell Curve was tremendous, to say the least. From an academic standpoint, this can not be thought of as a negative, and I am reminded of the work of Levay and the attention he received to a lesser extent.

The difficulty lies in the fact that soon after the release of the book, affirmative action became a matter of national debate in Congress, as well as in the journals. The politicians cited the book, and took the message to heart. I can recall reading the front page of USA Today, in which the lead article mentioned why psychologists felt as if affirmative action failed. The book reads like a great prosecuting attorney, talking to the jury about the events prior to the day of the crime. The story is long, emotional, selective, and nothing is added to the story unless it helps establish the one point that the person at hand is guilty. From the first chapter on, it is clear that the book is a setup for the later chapters.

The arguments of Hernstein and Murray are to be taken seriously. As Rushton and Jensen have attempted to put forth an agenda of intellectual superiority, so have the authors of The Bell Curve . The claims of intellectual group superiority has held back women and minorities since the mid 1800's (Rollins, 1996). It is hoped that the debates against The Bell Curve put to rest in the claims that intelligence is tied to a gene that is related to skin color.


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