This rather long article tells us calmly and judiciously that
there are differences in black and white Intelligence
with blacks rating about one standard deviation lower. He also tells that men
and women are different intellectually as well as physically. His most important
point is that these differences should be acknowledged openly because the taboo
leads to bad policy decisions.
The Inequality Taboo, by
Charles Murray
When the late Richard Herrnstein
and I published The Bell Curve eleven years ago, the furore over its
discussion of ethnic differences in IQ was so intense that most people who have
not read the book still think it was about race. Since then, I have deliberately
not published anything about group differences in IQ, mostly to give the real
topic of The Bell Curve—the role of intelligence in reshaping America’s
class structure—a chance to surface. The Lawrence Summers affair last
January made me rethink my silence. The president of Harvard University offered
a few mild, speculative, off-the-record remarks about innate differences between
men and women in their aptitude for high-level science and mathematics, and was
treated by Harvard’s faculty as if he were a crank. The typical news story
portrayed the idea of innate sex differences as a renegade position that
reputable scholars rejected. It was depressingly familiar. In
the autumn of 1994, I had watched with dismay as The Bell Curve’s
scientifically unremarkable statements about black IQ were successfully labelled
as racist pseudoscience. At the opening of 2005, I watched as some
scientifically unremarkable statements about male-female differences were
successfully labelled as sexist pseudoscience. The Orwellian disinformation
about innate group differences is not wholly the media’s fault. Many academics
who are familiar with the state of knowledge are afraid to go on the record.
Talking publicly can dry up research funding for senior professors and can cost
assistant professors their jobs. But while the public’s misconception is
understandable, it is also getting in the way of clear thinking about American
social policy. Good social policy can be based
on premises that have nothing to do with scientific truth. The premise that is
supposed to undergird all of our social policy, the founders’ assertion of an
unalienable right to liberty, is not a falsifiable hypothesis. But specific
policies based on premises that conflict with scientific truths about human
beings tend not to work. Often they do harm. One such premise is that the
distribution of innate abilities and propensities is the same across different
groups. The statistical tests for uncovering job discrimination assume that men
are not innately different from women, blacks from whites, older people from
younger people, homosexuals from heterosexuals, Latinos from Anglos, in ways
that can legitimately affect employment decisions. Title IX of the Educational
Amendments of 1972 assumes that women are no different from men in their
attraction to sports. Affirmative action in all its forms assumes there are no
innate differences between any of the groups it seeks to help and everyone else.
The assumption of no innate differences among groups suffuses American social
policy. That assumption is wrong. When the outcomes that these
policies are supposed to produce fail to occur, with one group falling short,
the fault for the discrepancy has been assigned to society. It continues to be
assumed that better programs, better regulations, or the right court decisions
can make the differences go away. That assumption is also wrong. Hence this essay. Most of the
following discussion describes reasons for believing that some group differences
are intractable. I shift from “innate” to “intractable” to acknowledge how
complex is the interaction of genes, their expression in behaviour, and the
environment. “Intractable” means that, whatever the precise partitioning of
causation may be (we seldom know), policy interventions can only tweak the
difference at the margins. I will focus on two sorts of
differences: between men and women and between blacks and whites. Here are three
crucial points to keep in mind as we go along: 1. The differences I discuss
involve means and distributions. In all cases, the variation within groups is
greater than the variation between groups. On psychological and cognitive
dimensions, some members of both sexes and all races fall everywhere along the
range. One implication of this is that genius does not come in one colour or sex,
and neither does any other human ability. Another is that a few minutes of
conversation with individuals you meet will tell you much more about them than
their group membership does. 2. Covering both sex differences
and race differences in a single, non-technical article, I had to leave out much
in the print edition of this article. This online version is fully annotated and
includes extensive supplementary material. 3. The concepts of “inferiority”
and “superiority” are inappropriate to group comparisons. On most specific human
attributes, it is possible to specify a continuum running from “low” to “high,”
but the results cannot be combined into a score running from “bad” to “good.”
What is the best score on a continuum measuring aggressiveness? What is the
relative importance of verbal skills versus, say, compassion? Of spatial skills
versus industriousness? The aggregate excellences and shortcomings of human
groups do not lend themselves to simple comparisons. That is why the members of
just about every group can so easily conclude that they are God’s chosen people.
All of us use the weighting system that favours our group’s strengths.
(1)
II Rather than present a
telegraphic list of all the differences that I think have been established, I
will focus on the narrower question at the heart of the Summers controversy: as
groups, do men and women differ innately in characteristics that produce
achievement at the highest levels of accomplishment? I will limit my comments to
the arts and sciences. Since we live in an age when
students are likely to hear more about Marie Curie than about Albert Einstein,
it is worth beginning with a statement of historical fact: women have played a
proportionally tiny part in the history of the arts and sciences.
(4) Even
in the 20th century, women got only 2 percent of the Nobel Prizes in the
sciences—a proportion constant for both halves of the century—and 10 percent of
the prizes in literature. The Fields Medal, the most prestigious award in
mathematics, has been given to 44 people since it originated in 1936. All have
been men. The historical reality of male
dominance of the greatest achievements in science and the arts is not open to
argument. The question is whether the social and legal exclusion of women is a
sufficient explanation for this situation, or whether sex-specific
characteristics are also at work. Mathematics offers an entry
point for thinking about the answer. Through high school, girls earn better
grades in math than boys, but the boys usually do better on standardized tests.
(5)
The difference in means is modest, but the male advantage increases as the focus
shifts from means to extremes. In a large sample of mathematically gifted
youths, for example, seven times as many males as females scored in the top
percentile of the SAT mathematics test.
(6) We do
not have good test data on the male-female ratio at the top one-hundredth or top
one-thousandth of a percentile, where first-rate mathematicians are most likely
to be found, but collateral evidence suggests that the male advantage there
continues to increase, perhaps exponentially.
(7) Evolutionary biologists have
some theories that feed into an explanation for the disparity. In primitive
societies, men did the hunting, which often took them far from home. Males with
the ability to recognize landscapes from different orientations and thereby find
their way back had a survival advantage. Men who could process trajectories in
three dimensions—the trajectory, say, of a spear thrown at an edible mammal—also
had a survival advantage.
(8) Women
did the gathering. Those who could distinguish among complex arrays of
vegetation, remembering which were the poisonous plants and which the nourishing
ones, also had a survival advantage. Thus the logic for explaining why men
should have developed elevated three-dimensional visuospatial skills and women
an elevated ability to remember objects and their relative locations—differences
that show up in specialized tests today.
(9) Perhaps this is a just-so story.
(10)
Why not instead attribute the results of these tests to socialization? Enter the
neuroscientists. It has been known for years that, even after adjusting for body
size, men have larger brains than women. Yet most psychometricians conclude that
men and women have the same mean IQ (although debate on this issue is growing).
(11)
One hypothesis for explaining this paradox is that three-dimensional processing
absorbs the extra male capacity. In the last few years, magnetic-resonance
imaging has refined the evidence for this hypothesis, revealing that parts of
the brain’s parietal cortex associated with space perception are proportionally
bigger in men than in women.
(12) What does space perception have
to do with scores on math tests?
(13)
Enter the psychometricians, who demonstrate that when visuospatial ability is
taken into account, the sex difference in SAT math scores shrinks substantially.
(14) Why should the difference be so
much greater at the extremes than at the mean? Part of the answer is that men
consistently exhibit higher variance than women on all sorts of characteristics,
including visuospatial abilities, meaning that there are proportionally more men
than women at both ends of the bell curve.
(15)
Another part of the answer is that someone with a high verbal IQ can easily
master the basic algebra, geometry, and calculus that make up most of the items
in an ordinary math test. Elevated visuospatial skills are most useful for the
most difficult items.
(16) If
males have an advantage in answering those comparatively few really hard items,
the increasing disparity at the extremes becomes explicable. Seen from one perspective, this
pattern demonstrates what should be obvious: there is nothing inherent in being
a woman that precludes high math ability. But there remains a distributional
difference in male and female characteristics that leads to a larger number of
men with high visuospatial skills. The difference has an evolutionary rationale,
a physiological basis, and a direct correlation with math scores. Now put all this alongside the
historical data on accomplishment in the arts and sciences. In test scores, the
male advantage is most pronounced in the most abstract items. Historically, too,
it is most pronounced in the most abstract domains of accomplishment.
(17) In the humanities, the most
abstract field is philosophy—and no woman has been a significant original
thinker in any of the world’s great philosophical traditions. In the sciences,
the most abstract field is mathematics, where the number of great women
mathematicians is approximately two (Emmy
Noether [ a Jew - Editor ] definitely,
Sonya Kovalevskaya
maybe). In the other hard sciences, the contributions of great women scientists
have usually been empirical rather than theoretical, with leading cases in point
being Henrietta Leavitt, Dorothy Hodgkin, Lise Meitner, Irene Joliot-Curie, and
Marie Curie herself. In the arts, literature is the
least abstract and by far the most rooted in human interaction; visual art
incorporates a greater admixture of the abstract; musical composition is the
most abstract of all the arts, using neither words nor images. The role of women
has varied accordingly. Women have been represented among great writers
virtually from the beginning of literature, in East Asia and South Asia as well
as in the West. Women have produced a smaller number of important visual
artists, and none that is clearly in the first rank. No female composer is even
close to the first rank. Social restrictions undoubtedly damped down women’s
contributions in all of the arts, but the pattern of accomplishment that did
break through is strikingly consistent with what we know about the respective
strengths of male and female cognitive repertoires. Women have their own cognitive
advantages over men, many of them involving verbal fluency and interpersonal
skills. If this were a comprehensive survey, detailing those advantages would
take up as much space as I have devoted to a particular male advantage. But,
sticking with my restricted topic, I will move to another aspect of male-female
differences that bears on accomplishment at the highest levels of the arts and
sciences: motherhood. Regarding women, men, and
babies, the technical literature is as unambiguous as everyday experience would
lead one to suppose. As a rule, the experience of parenthood is more profoundly
life-altering for women than for men. Nor is there anything unique about humans
in this regard. Mammalian reproduction generally involves much higher levels of
maternal than paternal investment in the raising of children.
(18)
Among humans, extensive empirical study has demonstrated that women are more
attracted to children than are men, respond to them more intensely on an
emotional level, and get more and different kinds of satisfactions from
nurturing them. Many of these behavioural differences have been linked with
biochemical differences between men and women.
(19) Thus, for reasons embedded in
the biochemistry and neurophysiology of being female, many women with the
cognitive skills for achievement at the highest level also have something else
they want to do in life: have a baby. In the arts and sciences, forty is the
mean age at which peak accomplishment occurs, preceded by years of intense
effort mastering the discipline in question.
(20)
These are precisely the years during which most women must bear children if they
are to bear them at all. Among women who have become
mothers, the possibilities for high-level accomplishment in the arts and
sciences shrink because, for innate reasons, the distractions of parenthood are
greater. To put it in a way that most readers with children will recognize, a
father can go to work and forget about his children for the whole day. Hardly
any mother can do this, no matter how good her day-care arrangement or full-time
nanny may be. My point is not that women must choose between a career and
children, but that accomplishment at the extremes commonly comes from a
single-minded focus that leaves no room for anything but the task at hand.
(21) We
should not be surprised or dismayed to find that motherhood reduces the
proportion of highly talented young women who are willing to make that tradeoff. Some numbers can be put to this
observation through a study of nearly 2,000 men and women who were identified as
extraordinarily talented in math at age thirteen and were followed up 20 years
later. (22)
The women in the sample came of age in the 1970’s and early 1980’s, when women
were actively socialized to resist gender stereotypes. In many ways, these
talented women did resist. By their early thirties, both the men and women had
become exceptional achievers, receiving advanced degrees in roughly equal
proportions. Only about 15 percent of the women were full-time housewives. Among
the women, those who did and those who did not have children were equally
satisfied with their careers. And yet. The women with careers
were four-and-a-half times more likely than men to say they preferred to work
fewer than 40 hours per week. The men placed greater importance on “being
successful in my line of work” and “inventing or creating something that will
have an impact,” while the women found greater value in “having strong
friendships,” “living close to parents and relatives,” and “having a meaningful
spiritual life.” As the authors concluded, “these men and women appear to have
constructed satisfying and meaningful lives that took somewhat different forms.”
(23)
The different forms, which directly influence the likelihood that men will
dominate at the extreme levels of achievement, are consistent with a
constellation of differences between men and women that have biological roots. I have omitted perhaps the most
obvious reason why men and women differ at the highest levels of accomplishment:
men take more risks, are more competitive, and are more aggressive than women.
(24)
The word “testosterone” may come to mind, and appropriately. Much technical
literature documents the hormonal basis of personality differences that bear on
sex differences in extreme and venturesome effort, and hence in extremes of
accomplishment—and that bear as well on the male propensity to produce an
overwhelming proportion of the world’s crime and approximately 100 percent of
its wars. But this is just one more of the ways in which science is
demonstrating that men and women are really and truly different, a fact so
obvious that only intellectuals could ever have thought otherwise.
III
Lewontin’s position, which
quickly became a tenet of political correctness, carried with it a potential
means of being falsified. If he was correct, then a statistical analysis of
genetic markers would not produce clusters corresponding to common racial
labels. In the last few years, that test
has become feasible, and now we know that Lewontin was wrong.
(26)
Several analyses have confirmed the genetic reality of group identities going
under the label of race or ethnicity.
(27) In
the most recent, published this year, all but five of the 3,636 subjects fell
into the cluster of genetic markers corresponding to their self-identified
ethnic group.
(28)
When a statistical procedure, blind to physical characteristics and working
exclusively with genetic information, classifies 99.9 percent of the individuals
in a large sample in the same way they classify themselves, it is hard to argue
that race is imaginary. Homo sapiens actually falls into
many more interesting groups than the bulky ones known as “races.”
(29) As
new findings appear almost weekly, it seems increasingly likely that we are just
at the beginning of a process that will identify all sorts of genetic
differences among groups, whether the groups being compared are Nigerian blacks
and Kenyan blacks, lawyers and engineers, or Episcopalians and Baptists. At the
moment, the differences that are obviously genetic involve diseases (Ashkenazi
Jews and Tay-Sachs disease, black Africans and sickle-cell anaemia, Swedes and
hemochromatosis). As time goes on, we may yet come to understand better why,
say, Italians are more vivacious than Scots. Out of all the interesting and
intractable differences that may eventually be identified, one in particular
remains a hot button like no other: the IQ difference between blacks and whites.
What is the present state of our knowledge about it? There is no technical dispute on
some of the core issues. In the aftermath of The Bell Curve, the American
Psychological Association established a task force on intelligence whose report
was published in early 1996.
(30) The
task force reached the same conclusions as The Bell Curve on the size and
meaningfulness of the black-white difference. Historically, it has been about
one standard deviation
(31) in
magnitude among subjects who have reached adolescence;
(32)
cultural bias in IQ tests does not explain the difference; and the tests are
about equally predictive of educational, social, and economic outcomes for
blacks and whites. However controversial such assertions may still be in the
eyes of the mainstream media, they are not controversial within the scientific
community. The most important change in the
state of knowledge since the mid-1990’s lies in our increased understanding of
what has happened to the size of the black-white difference over time. Both the
task force and The Bell Curve concluded that some narrowing had occurred
since the early 1970’s. With the advantage of an additional decade of data, we
are now able to be more precise: (1) The black-white difference in scores on
educational achievement tests has narrowed significantly. (2) The black-white
convergence in scores on the most highly “g-loaded” tests—the tests that are the
best measures of cognitive ability—has been smaller, and may be unchanged, since
the first tests were administered 90 years ago. With regard to the difference in
educational achievement, the narrowing of scores on major tests occurred in the
1970’s and 80’s. In the case of the SAT, the gaps in the verbal and math tests
as of 1972 were 1.24 and 1.26 standard deviations respectively.
(33) By
1991, when the gaps were smallest (they have risen slightly since then), those
numbers had dropped by .37 and .35 standard deviations. The National Assessment of
Educational Progress (NAEP), which is not limited to college-bound students, is
preferable to the SAT for estimating nationally representative trends, but the
story it tells is similar.
(34)
Among students ages nine, thirteen, and seventeen, the black-white differences
in math as of the first NAEP test in 1973 were 1.03, 1.29, and 1.24 standard
deviations respectively. For nine-year-olds, the difference hit its all-time low
of .73 standard deviations in 2004, a drop of .30 standard deviations. But
almost all of that convergence had been reached by 1986, when the gap was .78
standard deviations. For thirteen-year-olds, the gap dropped by .45 standard
deviations, reaching its low in 1986. For seventeen-year-olds, the gap dropped
by .52 standard deviations, reaching its low in 1990. In the reading test, the
comparable gaps for ages nine, thirteen, and seventeen as of the first NAEP test
in 1971 were 1.12, 1.17, and 1.25 standard deviations. Those gaps had shrunk by
.38, .62, and .68 standard deviations respectively at their lowest points in
1988. (35)
They have since remained effectively unchanged. An analysis by Larry Hedges and
Amy Nowell uses a third set of data, examining the trends for high-school
seniors by comparing six large data bases from different time periods from 1965
to 1992. The black-white difference on a combined measure of math, vocabulary,
and reading fell from 1.18 to .82 standard deviations in that time, a reduction
of .36 standard deviations.
(36) So black and white academic
achievement converged significantly in the 1970’s and 1980’s, typically by more
than a third of a standard deviation, and since then has stayed about the same.
(37)
What about convergence in tests explicitly designed to measure IQ rather than
academic achievement?
(38) The
ambiguities in the data leave two defensible positions. The first is that the IQ
difference is about one standard deviation, effectively unchanged since the
first black-white comparisons 90 years ago. The second is that harbingers of a
narrowing difference are starting to emerge. I cannot settle the argument here,
but I can convey some sense of the uncertainty. The case for an unchanged
black-white IQ difference is straightforward. If you take all the black-white
differences on IQ tests from the first ones in World War I up to the present,
there is no statistically significant downward trend. Of course the results
vary, because tests vary in the precision with which they measure the general
mental factor (g) and samples vary in their size and representativeness. But
results continue to centre around a black-white difference of about 1.0 to 1.1
standard deviations through the most recent data.
(39) The case for a reduction has two
important recent results to work with. The first is from the 1997 re-norming of
the Armed Forces Qualification Test (AFQT), which showed a black-white
difference of .97 standard deviations.
(40)
Since the typical difference on paper-and-pencil IQ tests like the AFQT has been
about 1.10 standard deviations, the 1997 results represent noticeable
improvement.
(41) The second positive result comes from the 2003 standardization
sample for the Wechsler Intelligence Scale for Children (WISC-IV), which showed
a difference of .78 standard deviations, as against the 1.0 difference that has
been typical for individually administered IQ tests.
(42) One cannot draw strong
conclusions from two data points. Those who interpret them as part of an
unchanging overall pattern can cite another recent result, from the 2001
standardization of the Woodcock-Johnson intelligence test. In line with the
conventional gap, it showed an overall black-white difference of 1.05 standard
deviations and, for youths aged six to eighteen, a difference of .99 standard
deviations.
(43) There is more to be said on both
sides of this issue, but nothing conclusive.
(44)
Until new data become available, you may take your choice. If you are a
pessimist, the gap has been unchanged at about one standard deviation. If you
are an optimist, the IQ gap has decreased by a few points, but it is still close
to one standard deviation. The clear and substantial convergence that occurred
in academic tests has at best been but dimly reflected in IQ scores, and at
worst not reflected at all. Whether we are talking about
academic achievement or about IQ, are the causes of the black-white difference
environmental or genetic? Everyone agrees that environment plays a part. The
controversy is about whether biology is also involved. It has been known for many years
that the obvious environmental factors such as income, parental occupation, and
schools explain only part of the absolute black-white difference and none of the
relative difference. Black and white students from affluent neighbourhoods are
separated by as large a proportional gap as are blacks and whites from poor
neighbourhoods.
(45)
Thus the most interesting recent studies of environmental causes have worked
with cultural explanations instead of socioeconomic status.
(46) One example is Black American
Students in an Affluent Suburb: A Study of Academic Disengagement (2003) by
the Berkeley anthropologist John Ogbu, who went to Shaker Heights, Ohio, to
explore why black students in an affluent suburb should lag behind their white
peers. (47)
Another is Black Rednecks and White Liberals (2005) by Thomas Sowell, who
makes the case that what we think of as the dysfunctional aspects of urban black
culture are a legacy not of slavery but of Southern and rural white “Crackers”
culture. (48)
Both Ogbu and Sowell describe ingrained parental behaviours and student attitudes
that must impede black academic performance. These cultural influences often cut
across social classes. From a theoretical standpoint,
the cultural explanations offer fresh ways of looking at the black-white
difference at a time when the standard socioeconomic explanations have reached a
dead end. From a practical standpoint, however, the cultural explanations point
to a cause of the black-white difference that is as impervious to manipulation
by social policy as causes rooted in biology. If there is to be a rapid
improvement, some form of mass movement with powerful behavioural consequences
would have to occur within the black community. Absent that, the best we can
hope for is gradual cultural change that is likely to be measured in decades. This brings us to the state of
knowledge about genetic explanations. “There is not much direct evidence on this
point,” said the American Psychological Association’s task force dismissively,
“but what little there is fails to support the genetic hypothesis.”
(49)
Actually, there is no direct evidence at all, just a wide variety of indirect
evidence, almost all of which the task force chose to ignore.
(50) As it happens, a comprehensive
survey of that evidence, and of the objections to it, appeared this past June in
the journal Psychology, Public Policy, and Law. There, J. Philippe
Rushton and Arthur Jensen co-authored a 60-page article entitled “Thirty Years
of Research on Race Differences in Cognitive Ability.”
(51) It
incorporates studies of East Asians as well as blacks and whites and concludes
that the source of the black-white-Asian difference is 50- to 80-percent
genetic. The same issue of the journal includes four commentaries, three of them
written by prominent scholars who oppose the idea that any part of the
black-white difference is genetic.
(52)
Thus, in one place, you can examine the strongest arguments that each side in
the debate can bring to bear. Rushton and Jensen base their
conclusion on ten categories of evidence that are consistent with a model in
which both environment and genes cause the black-white difference and
inconsistent with a model that requires no genetic contribution.
(53) I
will not try to review their argument here, or the critiques of it. All of the
contributions can be found on the Internet, and can be understood by readers
with a grasp of basic statistical concepts.
(54) For those who consider it
important to know what percentage of the IQ difference is genetic, a methodology
that would do the job is now available. In the United States, few people
classified as black are actually of 100-percent African descent (the average
American black is thought to be about 20-percent white).
(55) To
the extent that genes play a role, IQ will vary by racial admixture. In the
past, studies that have attempted to test this hypothesis have had no accurate
way to measure the degree of admixture, and the results have been accordingly
muddy. (56)
The recent advances in using genetic markers solves that problem. Take a large
sample of racially diverse people, give them a good IQ test, and then use
genetic markers to create a variable that no longer classifies people as “white”
or “black,” but along a continuum. Analyze the variation in IQ scores according
to that continuum. The results would be close to dispositive.
(57) None of this is important for
social policy, however, where the issue is not the source of the difference but
its intractability. Much of the evidence reviewed by Rushton and Jensen bears on
what we can expect about future changes in the black-white IQ difference. My own
thinking on this issue is shaped by the relationship of the difference to a
factor I have already mentioned—“g”—and to the developing evidence for g’s
biological basis. When you compare black and white
mean scores on a battery of subtests, you do not find a uniform set of
differences; nor do you find a random assortment. The size of the difference
varies systematically by type of subtest. Asked to predict which subtests show
the largest difference, most people will think first of ones that have the most
cultural content and are the most sensitive to good schooling. But this natural
expectation is wrong. Some of the largest differences are found on subtests that
have little or no cultural content, such as ones based on abstract designs. As long ago as 1927, Charles
Spearman, the pioneer psychometrician who discovered g, proposed a hypothesis to
explain the pattern: the size of the black-white difference would be “most
marked in just those [subtests] which are known to be saturated with g.”
(58) In
other words, Spearman conjectured that the black-white difference would be
greatest on tests that were the purest measures of intelligence, as opposed to
tests of knowledge or memory. A concrete example illustrates
how Spearman’s hypothesis works. Two items in the Wechsler and Stanford-Binet IQ
tests are known as “forward digit span” and “backward digit span.” In the
forward version, the subject repeats a random sequence of one-digit numbers
given by the examiner, starting with two digits and adding another with each
iteration. The subject’s score is the number of digits that he can repeat
without error on two consecutive trials. Digits-backward works exactly the same
way except that the digits must be repeated in the opposite order. Digits-backward is much more
g-loaded than digits-forward. Try it yourself and you will see why.
Digits-forward is a straightforward matter of short-term memory. Digits-backward
makes your brain work much harder.
(59) The black-white difference in
digits-backward is about twice as large as the difference in digits-forward.
(60)
It is a clean example of an effect that resists cultural explanation. It cannot
be explained by differential educational attainment, income, or any other
socioeconomic factor. Parenting style is irrelevant. Reluctance to “act white”
is irrelevant. Motivation is irrelevant. There is no way that any of these
variables could systematically encourage black performance in digits-forward
while depressing it in digits-backward in the same test at the same time with
the same examiner in the same setting.
(61) In 1980, Arthur Jensen began a
research program for testing Spearman’s hypothesis. In his book The g Factor
(1998), he summarized the results from seventeen independent sets of data,
derived from 149 psychometric tests. They consistently supported Spearman’s
hypothesis.
(62) Subsequent work has added still more evidence.
(63)
Debate continues about what the correlation between g-loadings and the size of
the black-white difference means, but the core of Spearman’s original
conjecture, that a sizable correlation would be found to exist, has been
confirmed.
(64) During the same years that
Jensen was investigating Spearman’s hypothesis, progress was also being made in
understanding g. For decades, psychometricians had tried to make g go away.
Confident that intelligence must be more complicated than a single factor, they
strove to replace g with measures of uncorrelated mental skills. They thereby
made valuable contributions to our understanding of intelligence, which really
does manifest itself in different ways and with different profiles, but getting
rid of g proved impossible. No matter how the data were analyzed, a single
factor kept dominating the results.
(65) By the 1980’s, the robustness
and value of g as an explanatory construct were broadly accepted among
pyschometricians, but little was known about its physiological basis.
(66) As
of 2005, we know much more. It is now established that g is by far the most
heritable component of IQ.
(67) A
variety of studies have found correlations between g and physiological phenomena
such as brain-evoked potentials, brain pH levels, brain glucose metabolism,
nerve-conduction velocity, and reaction time.
(68)
Most recently, it has been determined that a highly significant relationship
exists between g and the volume of gray matter in specific areas of the frontal
cortex, and that the magnitude of the volume is under tight genetic control.
(69)
In short, we now know that g captures something in the biology of the brain. So Spearman’s basic conjecture
was correct—the size of the black-white difference and g-loadings are
correlated—and g represents a biologically grounded and highly heritable
cognitive resource. When those two observations are put together, a number of
characteristics of the black-white difference become predictable, correspond
with phenomena we have observed in data, and give us reason to think that not
much will change in the years to come.
(70) One implication is that
black-white convergence on test scores will be greatest on tests that are least
g-loaded. Literacy is the obvious example: people with a wide range of IQ’s can
be taught to read competently, and it is the reading test of the NAEP in which
convergence has reached its closest point (.55 standard deviations in the 1988
test). More broadly, the confirmation of Spearman’s hypothesis explains why the
convergence that has occurred on academic achievement tests has not been matched
on IQ tests. A related implication is that
the source of the black-white difference lies in skills that are hardest to
change. Being able to repeat many digits backward has no value in itself. It
points to a valuable underlying mental ability, in the same way that percentage
of fast-twitch muscle fibres points to an underlying athletic ability. If you
were to practice reciting digits backward for a few days, you could increase
your score somewhat, just as training can improve your running speed somewhat.
But in neither case will you have improved the underlying ability.
(71) As
far as anyone knows, g itself cannot be coached. The third implication is that
the “Flynn effect” will not close the black-white difference. I am referring
here to the secular increase in IQ scores over time, brought to public attention
by James Flynn.
(72) The
Flynn effect has been taken as a reason for thinking that the black-white
difference is temporary: if IQ scores are so malleable that they can rise
steadily for several decades, why should not the black-white difference be
malleable as well?
(73) But as the Flynn effect has been
studied over the last decade, the evidence has grown, and now seems persuasive,
that the increases in IQ scores do not represent significant increases in g.
(74)
What the increases do represent—whether increases in specific mental skills or
merely increased test sophistication—is still being debated. But if the
black-white difference is concentrated in g and if the Flynn effect does not
consist of increases in g, the Flynn effect will not do much to close the gap. A
2004 study by Dutch scholars tested this question directly. Examining five large
databases, the authors concluded that “the nature of the Flynn effect is
qualitatively different from the nature of black-white differences in the United
States,” and that “the implications of the Flynn effect for black-white
differences appear small.”
(75) These observations represent my
reading of a body of evidence that is incomplete, and they will surely have to
be modified as we learn more. But taking the story of the black-white IQ
difference as a whole, I submit that we know two facts beyond much doubt. First,
the conventional environmental explanation of the black-white difference is
inadequate. Poverty, bad schools, and racism, which seem such obvious culprits,
do not explain it. Insofar as the environment is the cause, it is not the sort
of environment we know how to change, and we have tried every practical remedy
that anyone has been able to think of. Second, regardless of one’s reading of
the competing arguments, we are left with an IQ difference that has, at best,
narrowed by only a few points over the last century. I can find nothing in the
history of this difference, or in what we have learned about its causes over the
last ten years, to suggest that any faster change is in our future. IV
The taboo is not
perfect—otherwise, I would not have been able to document this essay—but it is
powerful. Witness how few of Harvard’s faculty who understood the state of
knowledge about sex differences were willing to speak out during the Summers
affair. In the public-policy debate, witness the contorted ways in which even
the opponents of policies like affirmative action frame their arguments so that
no one can accuse them of saying that women are different from men or blacks
from whites. Witness the unwillingness of the mainstream
media to discuss group
differences without assuring readers that the differences will disappear when
the world becomes a better place. The taboo arises from an
admirable idealism about human equality. If it did no harm, or if the harm it
did were minor, there would be no need to write about it. But taboos have
consequences. The nature of many of the
consequences must be a matter of conjecture because people are so fearful of
exploring them.
(76)
Consider an observation furtively voiced by many who interact with civil
servants: that government is riddled with people [ the
Diversity Hires ]
who have been promoted to their
level of incompetence because of pressure to have a staff with the correct sex
and ethnicity in the correct proportions and positions. Are these just
anecdotes? Or should we be worrying about the effects of affirmative action on
the quality of government services?
(77) It
would be helpful to know the answers, but we will not so long as the taboo
against talking about group difference prevails. How much damage has the taboo
done to the education of children? Christina Hoff Sommers has argued that willed
blindness to the different developmental patterns of boys and girls has led many
educators to see boys as aberrational and girls as the norm, with pervasive
damage to the way our elementary and secondary schools are run.
(78) Is
she right? Few have been willing to pursue the issue lest they be required to
talk about innate group differences. Similar questions can be asked about the
damage done to medical care, whose practitioners have only recently begun to
acknowledge the ways in which ethnic groups respond differently to certain
drugs.
(79) How much damage has the taboo
done to our understanding of America’s social problems? The part played by
sexism in creating the ratio of males to females on mathematics faculties is not
the ratio we observe but what remains after adjustment for male-female
differences in high-end mathematical ability. The part played by racism in
creating different outcomes in black and white poverty, crime, and illegitimacy
is not the raw disparity we observe but what remains after controlling for group
characteristics. For some outcomes, sex or race differences nearly disappear
after a proper analysis is done. For others, a large residual difference
remains. (80)
In either case, open discussion of group differences would give us a better
grasp on where to look for causes and solutions. What good can come of raising
this divisive topic? The honest answer is that no one knows for sure. What we do
know is that the taboo has crippled our ability to explore almost any topic that
involves the different ways in which groups of people respond to the world
around them—which means almost every political, social, or economic topic of any
complexity. Thus my modest recommendation,
requiring no change in laws or regulations, just a little more gumption. Let us
start talking about group differences openly—all sorts of group differences,
from the visuospatial skills of men and women to the vivaciousness of Italians
and Scots. Let us talk about the nature of the manly versus the womanly virtues.
About differences between Russians and Chinese that might affect their adoption
of capitalism. About differences between Arabs and Europeans that might affect
the assimilation of Arab immigrants into European democracies. About differences
between the poor and non-poor that could inform policy for reducing poverty. Even to begin listing the topics
that could be enriched by an inquiry into the nature of group differences is to
reveal how stifled today’s conversation is. Besides liberating that
conversation, an open and undefensive discussion would puncture the irrational
fear of the male-female and black-white differences I have surveyed here. We
would be free to talk about other sexual and racial differences as well, many of
which favour women and blacks, and none of which is large enough to frighten
anyone who looks at them dispassionately. Talking about group differences
does not require any of us to change our politics. For every implication that
the Right might seize upon (affirmative-action quotas are ill-conceived),
another gives fodder to the Left (innate group differences help rationalize
compensatory redistribution by the state).
(81) But
if we do not need to change our politics, talking about group differences
obligates all of us to renew our commitment to the ideal of equality that Thomas
Jefferson had in mind when he wrote as a self-evident truth that all men are
created equal. Steven Pinker put that ideal in today’s language in The Blank
Slate, writing that “Equality is not the empirical claim that all groups of
humans are interchangeable; it is the moral principle that individuals should
not be judged or constrained by the average properties of their group.”
(82) Nothing in this essay implies
that this moral principle has already been realized or that we are powerless to
make progress. In elementary and secondary education, many outcomes are
tractable even if group differences in ability remain unchanged. Dropout rates,
literacy, and numeracy are all tractable. School discipline, teacher
performance, and the quality of the curriculum are tractable. Academic
performance within a given IQ range is tractable. The existence of group
differences need not and should not discourage attempts to improve schooling for
millions of American children who are now getting bad educations. In university education and in
the world of work, overall openness of opportunity has been transformed for the
better over the last half-century. But the policies we now have in place are
impeding, not facilitating, further progress. Creating double standards for
physically demanding jobs so that women can qualify ensures that men in those
jobs will never see women as their equals. In universities, affirmative action
ensures that the black-white difference in IQ in the population at large is
brought onto the campus and made visible to every student. The intentions of
their designers notwithstanding, today’s policies are perfectly fashioned to
create separation, condescension, and resentment—and so they have done. The world need not be that way.
Any university or employer that genuinely applied a single set of standards for
hiring, firing, admitting, and promoting would find that performance across
different groups really is distributed indistinguishably. But getting to that
point nationwide will require us to jettison an apparatus of laws, regulations,
and bureaucracies that has been 40 years in the making. That will not happen
until the conversation has opened up. So let us take one step at a time. Let us
stop being afraid of data that tell us a story we do not want to hear, stop the
name-calling, stop the denial, and start facing reality. CHARLES MURRAY is the W.H. Brady
Scholar in Freedom and Culture at the American Enterprise Institute. His
previous contributions to COMMENTARY, available online, include “The Bell
Curve and Its Critics” (May 1995, with a subsequent exchange in the August
1995 issue). My thanks go to Michael Ashton,
Thomas Bouchard, Gregory Carey, Christopher DeMuth, David Geary, Linda
Gottfredson, Arthur Jensen, John Loehlin, David Lubinski, Kevin McGrew, Richard
McNally, Derek Neal, Steven Pinker, Philip Roth, Philippe Rushton, Sally Satel,
Christina Hoff Sommers, Hua Tang, Marley Watkins, Lawrence Weiss, and James Q.
Wilson for responding to questions or commenting on drafts. Their appearance on
this list does not imply their endorsement of anything in the essay. 1.
If you think this is mushy nonjudgmentalism, try a thought experiment: Suppose
that a pill exists that, if all women took it, would give them exactly the same
mean and variance on every dimension of human functioning as men—including all
the ways in which women now surpass men. How many women would want all women to
take it? Or suppose that the pill, taken by all blacks, would give them exactly
the same mean and variance on every dimension of human functioning as
whites—including all the ways in which blacks now surpass whites. How many
blacks would want all blacks to take it? To ask such questions is to answer
them: hardly anybody. Few want to trade off the unique virtues of their own
group for the advantages that another group may enjoy. Sometimes these preferences for
one’s own group are rational, sometimes not. I am proud of being Scots-Irish,
for example, even though the Scots-Irish group means for violence, drunkenness,
and general disagreeableness seem to have been far above those of other
immigrant groups. But the Scots-Irish made great pioneers—that’s the part of my
heritage that I choose to value. A Thai friend gave me an insight into this
human characteristic many years ago when I remarked that Thais were completely
undefensive about Westerners despite the economic backwardness of Thailand in
those days. My friend explained why. America has wealth and technology that
Thailand does not have, he acknowledged, just as the elephant is stronger than a
human. “But,” he said with a shrug, “who wants to be an elephant?” None of us
wants to be an elephant and, from the perspective of our own group, every other
group has something of the elephant about it. All of us are right, too. 2.
Geary (1998). 3.
Pinker (2002). A non-technical book-length treatment is Rhoads (2004). Halpern
(2000) and Kimura (1999) are good one-volume discussions of cognitive
differences between the sexes. An up-to-date summary of neuro-physiological
findings about sex differences in the brain appeared in last May’s Scientific
American, Cahill (2005). Baron-Cohen (2003) is an ambitious attempt to tie
together known sex differences into an overall theory. Those who want to compare
these accounts with defenses of the no-innate-differences position can look at
Valian (1999) and a set of essays weighted toward social explanations of math
differences in Gallagher and Kaufman (2005). 4.
My discussion of women and accomplishment in the arts and sciences is in Murray
(2003): 265–293. For a complementary discussion, see Simonton (1999): chapter 6. 5.
For the story on grades, see Kimball (1989). For a review of the literature on
male-female differences in means and methods of mathematical processing, see
Geary, Saults, Liu et al. (2000). For discussions of sex stereotyping, see Brown
and Josephs (1999), Stipek and Gralinski (1991), and several of the essays in
Gallagher and Kaufman (2005). 6.
This ratio is based on the percentages of boys and girls from Talent Search who
later, as high-school students, got the top possible score in the SAT-Math (12.7
percent of males and 1.9 percent of females, given in Lubinski, Benbow, Shea et
al., 2001). Julian Stanley, who has been associated with Talent Search for many
years, is said to have asserted in an interview that the male:female ratio among
such students has dropped to about 3 to 1. I have not been able to locate the
interview or any data substantiating that ratio. In any case, here is a
reminder: currently, the 800 top score in the SAT-Math is only about 2.6
standard deviations above the mean—that is, it includes about one in 200
test-takers. This is nowhere close to the extreme right end of the bell curve
from which top mathematicians are drawn. 7.
Nyborg (in press) finds a sex difference in the general mental ability g, not
just in spatial skills, and evidence that the male advantage increases
exponentially as distance from the mean increases. 8.
For a review of studies about sex differences in throwing ability, see Geary
(1998): 213–14, 284–85. For a presentation of the evolutionary explanation, see
Jones, Braithwaite, and Healy (2003) and Kimura (1999): 11–30. It has also been
argued that spatial skills were an advantage in tool-making. See Wynn, Tierson,
and Palmer (1996). 9.
Geary (1998): 286–90; Kimura (1999): 43–66. 10.
A continuing problem for evolutionary biology is the accusation that its
scholars observe human characteristics today and work backward into a rationale
that fits. But a sex difference in visuospatial abilities is found in many other
animals besides humans, always favoring males—which gives good reason for
thinking that in this case we are observing something more than a just-so story.
See Jones, Braithwaite, and Healy (2003). 11.
For a review of the evidence that male and female IQ is the same, see Jensen
(1998): 536–42. The underlying problem is that the subtests in IQ tests have
been developed and normed in ways that tend to push male and female IQs toward
the same mean IQ (for example, items that show a large sex difference are
usually discarded). For the evidence that men have a higher mean IQ than women,
see Ankney (1992), Lynn (1999), Lynn and Irwing (2004), and Nyborg (in press). 12.
See Goldstein, Seidman, Horton et al. (2001) and the interpretation of those
findings in Cahill (2005). This is far from a settled issue. Research into the
neurophysiology of sex differences is exploring a variety of trails. For
example, Gron, Spitzer, Tomczak et al. (2000) discovered that men and women
activate different parts of the brain when they are working out navigation
tasks, and do so in patterns consistent with the proposition that navigation is
cognitively more difficult for women. Consistent evidence also links the size of
brain regions with level of capability (Cahill 2005). This relationship between
specific parts of the brain and capability holds at an aggregate level as well:
IQ is correlated with brain size (adjusted for body size). The relationship of
brain size to IQ has often been derided (e.g., Gould 1981), and indeed brain
size was a problematic measure when it had to be based on skull size or
post-mortem data. But magnetic resonance imaging (MRI) studies of brain size
have ended the uncertainty about the existence of its relationship with IQ. For
meta-analyses of MRI and other in vivo studies, see Jensen (1998): 147,
which puts the correlation between brain size and IQ at about .40, and McDaniel
(2005), which puts it at about .33. 13.
E.g., Johnson (1984), Casey, Nuttall, Pezaris et al. (1995), and Geary, Saults,
Liu et al. (2000). There has been dispute on this point. Friedman (1995) argues
that performance in math tests is more strongly related to verbal ability than
to visuospatial abilities. Royer, Tronsky, Chan et al. (1999) present evidence
that the real source of the male advantage is faster retrieval of arithmetic
facts from long-term memory. A third line of argument has been that the apparent
male advantage is actually mediated by IQ (e.g., Linn and Peterson 1985). Geary,
Saults, Liu et al. (2000) controlled for IQ and found that both visuospatial
abilities and the computational advantage found by Royer, Tronsky, Chan et al.
(1999) were at work. 14.
Casey, Nuttall, Pezaris et al. (1995). 15.
Pinker (2002): 344–45. 16.
Visuospatial skills are helpful across the entire range of items (see Geary,
Saults, Liu et al. 2000), but good verbal skills can substitute in solving the
less difficult items. 17.
For a more detailed presentation of the evidence about the pattern of female
accomplishment in the arts and sciences, see Murray (2003): 265–69. 18.
Geary (1998): 20–28, 97–120. 19.
For an analysis of sex differences in nurturing, written by a committed feminist
who is also a scientist (an anthropologist), see Hrdy (1999). For a short review
of studies on the importance of children and of the biological sources of
nurturing differences, see Rhoads (2004): 190–222. 20.
Simonton (1984): chapter 6. 21.
Ochse (1990), Simonton (1994): chapter 5. 22.
Benbow, Lubinski, Shea et al. (2000). 23.
Ibid., 479. The figures in the text combine the data reported for two separate
cohorts. 24.
For a meta-analysis of sex differences in risk-taking, see Byrnes, Miller, and
Schafer (1999). For a discussion of the role of testosterone, see J.M. Dabbs and
M.G. Dabbs (2000). 25.
Lewontin (1972). 26.
For a technical description of what has been labeled “Lewontin’s fallacy,” see
Edwards (2003). For a nontechnical statement of how the understanding of this
issue has been changing, see Leroi (2005). 27.
Studies incorporating some variant of this type of analysis include Bamshad,
Wooding, Watkins et al. (2003), Bowcock, Ruiz-Linares, Romfohrde et al. (1994),
Calafell, Shuster, Speed et al. (1998), Mountain and Cavalli-Sforza (1997),
Rosenberg, Pritchard, Weber et al. (2002), and Stephens, Schneider, Tanguay et
al. (2001). 28.
Tang, Quertermous, Rodriguez et al. (2005). The self-identified ethnic groups
consisted of non-Hispanic black, non-Hispanic white, East Asian, and Hispanic.
The statistical procedure was cluster analysis. The algorithms in cluster
analysis are not trying to find groupings that correspond to any pre-identified
characteristic of the people in the sample—that is, the researchers did not use
any information about the physical characteristics that humans use to identify
ethnicity. Cluster analysis simply looks for interrelationships among the
genetic markers that identify statistically distinct entities. 29.
In Tang, Quertermous, Rodriguez et al. (2005), “Hispanic” corresponded to a
cluster, even though no one thinks of “Hispanic” as a race. People do not need
to belong to different races, conventionally defined, to be genetically
distinct. 30.
Neisser, Boodoo, Bouchard et al. (1996). 31.
The standard deviation is a statistic that (simplified) expresses the average
difference of all the scores from the mean. More precisely, the standard
deviation is calculated by squaring the deviation from the mean for each score,
summing all those squared deviations, finding the mean of that sum, then taking
the square root of the result. Given a normal distribution—a bell curve—someone
who is one standard deviation above the mean is at the 84th percentile. Two
standard deviations above the mean put that person at the 98th percentile. IQ
tests are normed to have a mean of 100 and a standard deviation of 15. 32.
The black-white difference emerges as early as IQ can be tested, but the gap is
usually smaller in pre-adolescence. Among pre-schoolers, the gap can be just a
few IQ points. Why does it increase with age? One obvious hypothesis is inferior
schooling—e.g., Fryer and Levitt (2004). But black children attending excellent
schools also fall behind their white counterparts, as discussed subsequently in
the text and in note 14. The alternative explanation is that the heritability of
IQ increases with age for people of all races, and this is reflected in black IQ
scores in adolescence and adulthood. See Jensen (1998): 178. 33.
My analysis of its annual College-Bound Seniors report, distributed as printed
material prior to 1996 and
available online from 1996 onward. A word about the method of
calculating the difference. When comparing scores from two groups, the preferred
method is to divide the difference in the two scores by the pooled standard
deviations of the two groups. The equation is
where N is the sample size, X is
the sample mean, s is the standard deviation, and the subscripts a and b denote
each group. When the black-white difference for a specific test is reported
subsequently in the text, this equation has been used to compute it. 34.
The Long Term
Trend Study with consistent data for the NAEP from the early 1970's through
2004 is now available in mathematics and reading for students tested at ages
nine, thirteen, and seventeen. 35.
For nine-year-olds, the gap in reading scores expressed as points was smaller in
2004 (26 points) than in 1988 (29 points), but the difference in standard
deviations was fractionally larger (.76 standard deviations in 2004 as compared
with .74 in 1988). 36.
Hedges and Nowell (1998): 154. 37.
I will venture a prediction that a variety of academic achievement measures in
elementary and secondary school will soon show renewed convergence because of
the No Child Left Behind Act, which puts schools under intense pressure to teach
to the test in basic skills. If students are drilled on limited ranges of
subject matter, scores will tend to rise. The more basic the tests are (that is,
the easier they are), the more that improvements among the least skilled will
affect the mean. Also, the higher the stakes facing a school—and the No Child
Left Behind Act makes those stakes very high indeed—the greater will be the
incentives for administrators to use some of the many resources at their
disposal to make the results come out right, through the judicious manipulation
of suspensions and absences, and through outright cheating (yes, it has been
known to happen). Some convergence in black and white test scores will probably
occur, but partitioning that effect among the competing explanations is a task
that will take a few years. Insofar as the convergence has been the result of
teaching to the test and of artifacts, it will be temporary. 38.
In a given year, IQ tests and academic tests administered to the same sample
will produce similar results. Thus, it is possible to make a reasonably good
guess about a person’s IQ based on his SAT score compared to the distribution of
SAT scores in a given year, and after taking the composition of the SAT
population into account. But the results of academic tests are sensitive to
changes in academic achievement, whereas IQ tests are explicitly designed to
measure a general mental factor, g, that is independent of academic achievement.
A notorious illustration of the way that academic test scores can drop is the
period during the 1960’s and 1970’s when SAT scores declined substantially, even
after accounting for changes in the pool of test-takers (Murray and Herrnstein
1992). The intelligence of American youth was not declining, just their academic
achievement. 39.
The significance of g-loadings is discussed later in the text. In terms of
interpreting trends over time, the problem is that tests are not equally good
measures of g. They go from poor (e.g., a basic reading test) to excellent (the
most highly g-loaded, individually administered IQ test). It is as if you were
trying to measure changes in average height with measuring tapes of varying
accuracy. For a statement of the no-change position, see Gottfredson (2005a), or
a summary of her argument in Gottfredson (2005b). 40.
The .97 figure comes from my analysis of the proxy AFQT score in the most recent
release of the 1997 cohort of the National Longitudinal Study of Youth (NLSY). I
call it a proxy score because, eight years after the test battery was
administered, the Armed Forces still has not gotten around to creating an
official AFQT score. The version created by the NLSY staff is a composite of the
same subtests used for previous versions of the AFQT, and takes the subject’s
age into account. The NLSY has released the percentile scores, which I converted
to standard scores. The analysis used the NLSY’s sample weights to make the
results representative of the national population. The NLSY data can be
downloaded online. 41.
I take the 1.10 figure from Roth, Bevier, Bobko et al. (2001), a meta-analysis
of the black-white difference in both achievement tests and IQ tests. The Roth
et al. results are necessarily reflective of pencil-and-paper tests, because
that is where the overwhelming majority of published test data come from. With
rare exceptions, the data on individually administered IQ tests such as the
Wechsler, Stanford-Binet, and Woodcock-Johnson are limited to their periodic
standardization samples. The number of such studies is small. These results are
overwhelmed in a meta-analysis by the many more studies based on
pencil-and-paper tests. The previous re-norming of the
AFQT occurred in 1979, when the AFQT was administered to the 1979 cohort of the
NLSY. Herrnstein and Murray (1994) put the black-white difference for that
cohort at 1.21 standard deviations. Compared with that figure, the improvement
in the 1997 cohort (a .97 black-white difference) is .24 standard deviations.
But Neal (in press) has uncovered patterns in the answers of black members of
the 1979 cohort that indicate the 1979 cohort produced an artificially low black
mean. First, some background: Any test
that tries to measure cognitive ability has to make assumptions about baseline
skills. If a person can read, even if not very well, then an IQ test can make
use of written items; if the subject is illiterate, it cannot. Similarly, if a
person knows numbers and the principles of basic arithmetic, even if not very
well, then an IQ test can make use of numeric problems; but if the subject is
innumerate, it cannot. Neal argues that the pattern of
answers for the 1979 cohort indicates that “a substantial fraction of the NLSY79
sample of black males who took the ASVAB test lacked the basic math and reading
skills covered by the exam, lacked any motivation to put forth effort during the
exam, or both,” with a similar situation, not quite as bad, for black females
(Neal, in press: 13) Given the convergence in academic test scores during the
1980’s, it is likely that the proportion of the 1997 NLSY cohort so completely
lacking in the basic skills was smaller than in the 1979 cohort. If so, this
change alone, not an increase in cognitive ability, would produce convergence in
the black-white difference in the AFQT. In addition, the administration of the
ASVAB in 1997 was computer-adaptive. Instead of being confronted with pages of
questions (105 of them) as in the traditional paper-and-pencil ASVAB (the kind
used in 1979), subjects saw one question at time, and the difficulty of each
subsequent question was adapted to the subject’s previous answer—a method less
likely to provoke the kind of give-up response that Neal found in the 1979 data.
Neal did not try to estimate the magnitude of the artifact in the 1979 data, but
if a “substantial fraction” of the NLSY males had unrealistically low scores,
some figure lower than 1.21 standard deviations would be appropriate as a
baseline for comparing the 1997 AFQT results. The overall black-white difference
of 1.10 standard deviations as found in the meta-analysis is the natural choice. 42.
The black and white means on the WISC-IV’s measure of full-scale IQ were 91.7
and 103.2 respectively (Prifitera, Weiss, Saklofske et al. 2005: 24). Standard
deviations for computing the black-white difference were supplied by the
Psychological Corporation, which produces the Wechsler tests. 43.
The 1.05 and .99 figures come from my analysis of data for the 2001
standardization sample for the Woodcock-Johnson III (WJ-III) test of cognitive
ability, provided courtesy of the Woodcock-Munoz Foundation. The results from
the WJ-III are noteworthy because the WJ-III provides the best known statistical
estimate of g. Uniquely among the major standardized tests, the scoring system
for the WJ-III uses principal-components analysis to find the best weighted
combination of subtests instead of treating all subtests equally (Schrank,
McGrew, and Woodcock 2001). 44.
Two resourceful defenders of the environmental hypothesis about the black-white
difference, James Flynn and William Dickens, are working on their own analysis
of the black-white difference over time that should materially add to the state
of knowledge when it is released. Here are a few examples of the ambiguities
that complicate the assessment of whether the IQ difference has changed, and
that have prevented me from stating a confident conclusion: Example 1. One of the few sources
that has several data points over time with a consistent measure is the General
Social Survey (GSS) available
online, conducted annually by the National Opinion Research Center; which in
most years through the 2000 survey, it included a ten-item vocabulary test. Example 2. The Kaufman Assessment
Battery for Children (K-ABC) is a test that has consistently shown smaller
black-white differences than other IQ tests. There are a number of reasons for
this, one being that subtests showing large black-white differences were
excluded (the K-ABC includes forward-digit span but not backward-digit span, for
example). See Jensen (1984) for a full discussion. But though the black-white
difference is smaller, it has not changed. In the manual for the original
standardization published in 1983, the means on the “Mental Processing
Composite” ( K-ABC’s version of an IQ score) for the white and black samples
were 102.0 and 95.0 respectively (A. S. Kaufman and Kaufman 1983: 152).
Twenty-one years later, those means were both within a point of their 1983
values—102.7 and 94.8 respectively (A.S. Kaufman and N.L. Kaufman 2004: 96).
Which is more meaningful? The smaller black-white difference shown by the K-ABC?
Or the absence of any convergence over time? Example 3. In trying to
discriminate between increases in IQ and improvements in academic achievement,
one strategy is to explore which parts of the distribution of scores show the
most change. Convergence that occurs because of improvements at the bottom of
the distribution is likely to reflect remediation of fundamental educational
deficits, which could leave the IQ distribution more or less untouched. In their analysis of six major
cross-sectional databases spanning the period from 1965 to 1992, Hedges and
Nowell (1998) found that “Racial disparities have diminished over time in the
lower tail, but not in the upper tail” (159). In the NAEP, they found that “From
1980 to 1988 there was a substantial increase at all points on the black
distribution, with much greater change in the lower percentiles” for the reading
scores, and a similar pattern for math scores (161). Another analysis, however, finds
that almost all of the improvement in scores has occurred among black students
in the upper half of the black distribution. For example, the AFQT math score of
a black male age 15–17 at the 70th percentile of the black distribution in 1980
was equivalent to the score of a white male at about the 28th percentile of the
white distribution (Neal, in press, Figure 2a). In 1997, a black male at the
70th percentile of the black distribution had risen to about the 40th percentile
of the white distribution. Neal finds a similar result for math scores in the
NAEP in the period 1978–1992/96 (Figures 2c and 2d). In contrast, Neal has found
almost no increases among students in the bottom half of the black distribution. How can the results from two
analyses be so different? The apparent contradiction—it is not a real
contradiction—arises from the fact that almost all of the improvement of blacks
in the upper half of the black distribution represents improvement in scores in
the lower half of the national distribution of scores. But return to the example
of the AFQT: even in 1997, a black subject with a score that put him at the 50th
percentile of the white distribution—in other words, a little above the overall
national mean—was at about the 80th percentile of the black distribution. In
1980, a black student had to be at about the 90th percentile of the black
distribution to have a score above the national mean. Which analysis should one use?
That depends on the topic for which one wants information. If the question is,
“Who improved their scores relative to whites, the students at the bottom of the
black distribution or the students at the top of it?,” Neal’s analysis provides
the correct answer. If the question is, “Did most of the improvement in black
scores occur at the bottom or the top of the national distribution of scores?,”
then Hedges and Nowell’s approach provides the correct answer. In deciding whether IQ has risen,
how does one balance these results? I am an optimist about the recent past. To
me, the various ambiguous indicators add up to the likelihood that a reduction
in the IQ gap has occurred alongside the reduction in the academic-achievement
gap. Forced to make a bet, I would guess that the black-white difference in IQ
has dropped by somewhere in the range of .10–.20 standard deviations over the
last few decades. I must admit, however, that I am influenced by a gut-level
conviction that the radical improvement in the political, legal, and economic
environment for blacks in the last half of the 20th century must have had an
effect on IQ. To conclude that no narrowing whatsoever has occurred raises the
question, “How can that be?” One would have to argue that all of the gains in
some aspects of the environment have been counterbalanced by new deficits in
other aspects, and that those new deficits affect different socioeconomic
classes similarly. If the argument is restricted to environmental changes, I
cannot imagine how that case might be made. Another possibility is that
improvement in the environmental causes of IQ has been counterbalanced by what
is known as “dysgenic” fertility. For several decades at least, women with the
highest IQs have been having the fewest babies, and black women have been no
different from anyone else (Herrnstein and Murray 1994: chapter 15). But the
problem is especially acute among blacks because it is not just black women
above the national average IQ who are having the fewest babies but women above
the black average. Consider the results for the women of the 1979 NLSY cohort,
whose childbearing years are effectively over (they ranged in age from
thirty-eight to forty-five when these numbers were collected). Using a
nationally representative subsample for the analysis, one finds that the mean
AFQT score of the black women was 85.7. Sixty percent of the children born to
this cohort were born to women with AFQT scores below that average. Another 33
percent were born to women with scores from 85.7 to 100. Only 7 percent were
born to women with IQs of 100 and over. Did the children do better? A
total of 716 of them were tested with a highly g-loaded verbal test, the Peabody
Picture Vocabulary Test (revised). The mean of the subset of mothers whose
children were tested was 83.7. The mean of their children was 80.2. The mothers
and children were tested with different instruments, so it should not be
concluded that the black mean actually went down in the new generation. But
these data certainly give no reason to think it went up. It is thus technically possible
that black IQ could have remained about the same during the last half-century
despite the revolutionary changes for the better in the status of black
Americans. Deciding whether that in fact happened requires more evidence than I
have presented here. When I try to forecast the
future, I become a pessimist. Here is how I read the overall patterns of change
in the academic achievement tests versus the IQ tests: In a world where Rushton and
Jensen are right and the black-white difference is 50- to 80-percent genetic,
academic performance and IQ will both improve as the environment improves, and
for the same reason: environment plays a role in both measures. Academic test
scores will begin to rise before IQ does, because academic performance can
improve immediately upon getting a better education whereas the environmental
factors affecting IQ are more diffuse. For a related reason—changes in the
quality of education can cause substantial increases or drops in academic
achievement, whereas IQ cannot be changed much by any known discrete,
time-limited environmental change—convergence will be greater in academic
achievement than in IQ. Since the environmental role is only 20 to 50 percent of
the total, the improvements in both academic and IQ test scores will eventually
level off as the limits of environmental change are reached. To me, the pattern we have
observed since good longitudinal data became available in the early 1970’s is
consistent with these expectations. The only surprise is that evidence for
convergence in IQ scores has been so slow to emerge and so spotty. I interpret
the pattern as indicating that convergence is nearing an asymptote and that not
much will change in the future. 45.
Blacks and whites have different distributions of socioeconomic status (SES),
and SES is correlated with IQ among both blacks and whites. When the difference
in black and white SES distributions is statistically controlled, studies have
typically found that the black-white difference is reduced by about a third of a
standard deviation. But when blacks and whites of similar socioeconomic status
are compared with each other, the difference as measured in standard deviations
remains the same or increases as SES goes up. For a review of the evidence on
this point, see Herrnstein and Murray (1994): 286–89. 46.
I put aside here the explanation that has received the most publicity in recent
years, the phenomenon labeled “stereotype threat.” Its discoverers, Claude
Steele and Joshua Aronson, demonstrated experimentally that test performance by
academically talented blacks was worse when a test was called an IQ test than
when it was innocuously described as a research tool (Steele and Aronson 1995).
Press reports erroneously interpreted this as meaning that stereotype threat
explained away the black-white difference. In reality, Steele and Aronson showed
only that it increases the usual black-white difference; if one eliminates
stereotype threat, the usual difference remains. The misrepresentation of these
results in the mainstream media was grotesque. For example, the narrator of the
PBS television program Frontline told his viewers that “blacks who believed the
test was merely a research tool did the same as whites.” The Boston Globe
reported that “Black students who think a test is unimportant match their white
counterparts’ scores.” Newsweek reported that “blacks who were told that the
test was a laboratory problem-solving task that was not diagnostic of ability
scored about the same as whites.” Such claims have now infiltrated major
psychology texts. The third edition of Psychology by Davis and Palladino
(2002) reports that “The results revealed that African-American students who
thought they were simply solving problems performed as well as white students.”
Similar statements have appeared in scientific journals. All of the above
examples are taken from Sackett, Hardison, and Cullen (2004). Sackett et al.
also have a nice description of how the research results should have been
described: “In the sample studied, there are no differences between groups in
prior SAT scores, as a result of the statistical adjustment. Creating stereotype
threat produces a difference in scores; eliminating threat returns to the
baseline condition of no difference” (9). Readers may follow the latest in
the debate by reading a set of responses to Sackett, Hardison, and Cullen (2004)
in the April 2005 issue of American Psychologist, but nothing in the
critiques overturns the above description. The existence of stereotype threat
has indeed been demonstrated. It is an interesting phenomenon, and some claims
have been made that reducing stereotype threat can improve scores on certain
tests (Good, Aronson, and Inzlicht 2003), but the widespread assertion that
stereotype threat explains a significant part of the observed black-white
difference is wrong. The dissemination of that false assertion is perhaps
understandable in the case of journalists who are not supposed to be
sophisticated about such topics. It is less easily explained away when done by
authors of technical articles and textbooks. 47.
Ogbu (2003). 48.
Sowell (2005). 49.
Neisser, Boodoo, Bouchard et al. (1996): 95. 50.
Neisser, Boodoo, Bouchard et al. (1996): 95. In truth, the closest thing to
direct evidence involves brain size, which is known to have a correlation with
IQ (see note 12) and to be different for blacks, whites, and East Asians. See
J.P. Rushton and E.W. Rushton (2003) for a recent literature review of the
evidence. But the task force did not mention brain size. There is also no
mention of IQ in sub-Saharan Africa, the results of transracial adoption
studies, the correlation of the black-white difference with the g-loadedness of
tests, regression to racial means across the range of IQ, or other relevant
data. What the task force chose to define as “direct evidence” was a study of
children of American black soldiers born to German women after World War II, and
studies that use blood-group methods to estimate the degree of African ancestry
in American blacks. Both are discussed at length in Rushton and Jensen (2005a)
and Nisbett (2005). 51.
Rushton and Jensen (2005a). 52.
The other articles are Sternberg (2005), Nisbett (2005), Suzuki and Aronson
(2005), Gottfredson (2005b), and Rushton and Jensen (2005b) 53.
The ten categories, following Rushton and Jensen’s wording, are as follow: (1)
the world-wide evidence of a consistent black-white-Asian difference, (2) the
greater black-white difference on g-loaded subtests than on culture-bound
subtests, (3) the greater black-white difference on highly heritable subtests
than on culturally malleable subtests, (4) the association of the
black-white-Asian difference with differences in brain size, (5) the persistence
of the black-white-Asian difference among trans-racial adoptees, (6) the
consistency of the black-white difference with studies of racial admixture, (7)
regression of black and white relatives (offspring or siblings) to their
respective racial means, (8) consistency of the black-white-Asian IQ differences
with differences in 60 other behavioral traits, (9) consistency of the
black-white-Asian differences with evolutionary explanations, and (10) the
inability to explain black-white-Asian differences with a zero-genetic model or
even with a 50-percent environmental model. 54.
Rushton has posted all of the articles at his
website. 55.
Chakraborty, Kamboh, Nwankwo et al. (1992), Parra, Marcini, Akey et al. (1998). 56.
A variety of studies, summarized in Rushton and Jensen (2005a): 260–61,
generally show that the IQs for mixed-race children are about midway between
those of children with two white and two black parents. On the other hand,
studies that characterized racial composition based on blood group do not
predict IQ (Nisbett 2005: 306–07). 57.
The results of such a study would be especially powerful if the study also
characterized variables like skin color, making it possible to compare the
results for subjects for whom genetic heritage and appearance are discrepant.
For example, suppose it were found that light-skinned blacks do better in IQ
tests than dark-skinned blacks even when their degree of African genetic
heritage is the same. This would constitute convincing evidence that social
constructions about race, not the genetics of race, influence the development of
IQ. Given a well-designed study, many such hypotheses about the conflation of
social and biological effects could be examined. 58.
Spearman (1927): 379. 59.
The average adult gets a digits-backward score of 5 (Jensen 1998: 263). You may
compare your own score with the highest I have observed, 13 and 12, achieved
respectively by José Zalaquett, former chairman of Amnesty International, and
the political analyst Charles Krauthammer. Zalaquett’s score might have been
higher if he had not been in a car weaving through traffic at 70 miles per hour
on the New Jersey Turnpike. Krauthammer’s score might have been higher if he
hadn’t been driving. 60.
Jensen (1998): 370. 61.
A similarly clean example of a black-white difference is produced by
reaction-time tests, in which two different measures are taken: the time it
takes for the subject to respond to the lighted buttons that constitute the
stimulus (a g-loaded measure) and the time it takes to move one’s finger from
the home button to the appropriate lighted button (no g-loading). Black subjects
have faster movement times and slower response times—once again a contrast,
consistent with Spearman’s hypothesis, produced at the same time with the same
examiner in the same setting. None of the usual ways to explain away the
black-white difference through cultural causes applies. See Jensen (1998):
389–93. 62.
Jensen (1998): 369–402. 63.
Nyborg and Jensen (2000). It should also be noted that one test of Spearman’s
hypothesis has been conducted comparing East Asians and whites. The better the
measure of g, the greater the advantage of East Asians over whites. See Nagoshi,
Johnson, DeFries et al. (1984). 64.
Jensen’s evidence has been accompanied by a debate over his method of correlated
vectors for testing Spearman’s hypothesis. P.H. Schönemann has argued, most
extensively in Schönemann (1997), that Jensen’s evidence was no more than a
statistical artifact, a claim refuted by Dolan and Lubke (2001). But other ways
in which the method of correlated vectors might yield spurious results are still
being debated; e.g., Dolan (2000), Lubke, Dolan, and Kelderman (2001), Dolan,
Roorda, and Wicherts (2004), Ashton and Lee (in press). These arguments are
being carried on at an arcane methodological level. I am making a limited claim
about what Jensen has established beyond dispute: when you take a battery of
mental tests, subject them to a factor analysis, and correlate the loadings on
the first factor with the size of the black-white difference, the correlation
will average about .6. The actual method of correlated vectors is more
complicated than this, and is described in Jensen (1998): 372–74. 65.
Factor analysis can be conducted in many different ways, which has led to
widespread popular acceptance of one of
Stephen Jay Gould's allegations in his
best-selling book,
The Mismeasure of
Man (1981), namely, that g is a
statistical artifact that appears only when certain analytic choices are made.
Actually, the opposite is true. A single factor, typically explaining about
three times as much variance as all the other factors combined, emerges under
all of the normal methods of conducting a factor analysis. The only exception
occurs if the factor-analysis program is explicitly instructed to apportion the
variance in such a way that a single factor does not emerge. But if you do that
and then try to publish your results, the reviewers will point out that if you
hadn’t issued that instruction, you would have gotten a dominant single factor.
As Richard Herrnstein liked to say, “You can make g hide, but you can’t make it
go away.” For a review of this issue with sources, see the Afterword to the
softcover edition of The Bell Curve (559–62). For a technical
demonstration of the convergent results from alternative ways of conducting a
factor analysis, see Ree and Earles (1991). For a wide-ranging set of articles
about the current role of g in understanding intelligence, see the articles in
the special section of the January 2004 issue of Journal of Personality & Social
Psychology commemorating the 100th anniversary of Spearman’s discovery of g. An
overview is given in Lubinski (2004). 66.
Gould (1981) still shapes the lay received wisdom about IQ tests, but his
denunciation of g was already technically outdated when it was published. For an
account of the differing ways in which The Mismeasure of Man was assessed
by the media and by scholars, see Davis (1983). For a recent discussion of the
nature of g and the issues that Gould was wrong about, see Bartholomew (2004). 67.
Jensen (1998): 182–89. 68.
Jensen (1998): 137–68. 69.
Haier, Jung, Yeo et al. (2004); Thompson, Cannon, Narr et al. (2001). 70.
Let it be clear: I am not asserting that putting these two facts together proves
that the black-white difference is genetic. The logic of the situation was
memorably converted to an analogy in Lewontin (1970) and adapted in Herrnstein &
Murray (1994): 298. If you take two handfuls of genetically identical seed corn
and plant one in Iowa and the other in the Mohave Desert, you will get a large
group difference in results despite the high heritability of the traits of corn.
William Dickens and James Flynn have operationalized the analogy through a
simulation model that produces a large black-white difference from environmental
factors even given high heritability (Dickens and Flynn 2001). The validity of
that model was subsequently disputed by Loehlin (2002) and Rowe and Rodgers
(2002), with a reply by Dickens and Flynn (2002). But that debate does not
pertain here. The implications I describe follow simply from knowing that g is
highly heritable among blacks, as it is among all groups, and that the
black-white difference is largely a difference in g. 71.
See te Nijenhuis, Voskuijl, and Schijve (2001), who also found evidence, as did
Neubauer and Freudenthaler (1994), that coaching also reduced the g-loadedness
of the test, and for the obvious reason: noise has been introduced into the IQ
score, changing the score but not the thing that makes an IQ test predictive, g.
An athletic analogy may be usefully pursued for understanding these results.
Suppose you have a friend who is a much better athlete than you, possessing
better depth perception, hand-eye coordination, strength, and agility. Both of
you try high-jumping for the first time, and your friend beats you. You practice
for two weeks; your friend doesn’t. You have another contest and you beat your
friend. But if tomorrow you were both to go out together and try tennis for the
first time, your friend would beat you, just as your friend would beat you in
high-jumping if he practiced as much as you did. 72.
Flynn (1984) is an early statement. Over the years since The Bell Curve
was published, it has been especially exasperating to be told, or to see it
written, that Herrnstein and I were wrong because we did not know about the
Flynn effect. We not only provided the first discussion of the Flynn effect
aimed at a general audience; we named it (Herrnstein and Murray 1994: 307–09).
Some scholars, notably J. Philippe Rushton, have subsequently called it the
“Lynn-Flynn effect,” thereby acknowledging Richard Lynn’s role in identifying
the rise in IQ scores. 73.
Flynn (1998). 74.
An early statement of this evidence, based on analysis of the g loadings of
subtests, is Jensen (1998): 320–21. Rushton (1999) elaborates, disputed in Flynn
(1999) and Flynn (2000), with a rejoinder in Rushton (2000). Since then the
evidence that the Flynn effect does not consist of increases in g has been
augmented by an independent method, multigroup confirmatory factor analysis (MGCFA),
which permits a test for factorial invariance between cohorts. In less technical
terms, the method tests for whether differences in IQ scores between groups
reflects true differences in g. See Lubke, Dolan, Kelderman et al. (2003) for a
description of the method and its uses. Wicherts, Dolan, Hessen et al. (2004)
used MGCFA on five large databases: Dutch adults in 1967/68 and 1998/99; Danish
draftees in 1988 and 1998; Dutch high-school students in 1984 and 1994/95; Dutch
children in 1981/82 and 1992/93; and Estonian children 1934/36 and 1997/98. The
authors found that the hypothesis of factor invariance was untenable, and that
the gains in intelligence-test scores were not manifestations of increases in g.
Previously, Dolan (2000) and Dolan & Hamaker (2001) had used the MGCFA to test
for factor invariance between blacks and whites on IQ tests, and had concluded
that the results passed the MGCFA test. In other words, the black-white
differences were consistent with a difference in g. It was this contrast in
results that led Wicherts and his colleagues to conclude that the Flynn effect
would have little effect on the black-white difference. 75.
Wicherts, Dolan, Hessen et al. (2004): 531. 76.
In the text I ignore Europe, where both academic and political elites have
suppressed the discussion of group differences even more effectively than in
America. Contemporaneously, the European Union has revolutionized free movement
within Europe. That, combined with immigration from outside Europe, legal and
illegal, has produced unprecedented population change in countries that
historically have been ethnically homogeneous. Immigration poses problems for
European countries that are qualitatively different from those faced by the
United States. Becoming an American requires only that immigrants buy into a set
of American ideals. You can move to America from anywhere in the world, be of
any ethnicity, social class, or race, and become an American. Assimilation is
what America does—not as well as it used to, but still pretty well. The European
Union’s immigration policy has, willy-nilly, decided that now you can move to
Denmark and become Danish or move to France and become French. Is this true?
Everyday experience suggests that Denmark’s culture works because it fits the
characteristics of Danes, that France’s culture works because it fits the
characteristics of the French, and that these ethnic characteristics are
importantly different and deeply rooted, whether in genes or in habits of the
heart. Replace a large proportion of French with Danes—let alone peoples more
distant—and French culture will be profoundly changed. But it is taboo among the
elites to talk about such things (although ordinary people sense what is at
stake), and so a momentous social experiment is under way without any reason to
think that its assumptions are correct, many historical reasons for thinking
they are wrong, and recurring stories on the evening news suggesting that the
social fabrics of Europe will be shredded before the elites can make themselves
come to grips with what they have been doing. 77.
A few systematic examinations of this issue have been published; e.g., Lott
(2000) on the effects of affirmative action on policing. For a journalistic
account of the effects of political correctness on the Los Angeles Police
Department, see Golab (2005). 78.
Sommers (2001). 79.
Satel (2002). 80.
For examples of the effects of controlling for group differences on a variety of
outcomes and groups, see Herrnstein and Murray (1994): chapter 14, Nyborg and
Jensen (2001), and Kanazawa (2005). 81.
See Pinker (2002): chapter 16 for a discussion of how politics interacts with
the acceptance of group differences. 82.
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Bible Research >
Political Correctness > Murray
The article below is
reproduced from the website of
Commentary magazine. It is a fully annotated version of the article that was
published in the September 2005 issue of Commentary [ and is not now
on line there - Ed. ]
The Inequality Taboo
by Charles Murray
The technical literature
documenting sex differences and their biological basis grew surreptitiously
during feminism’s heyday in the 1970’s and 1980’s. By the 1990’s, it had become
so extensive that the bibliography in David Geary’s pioneering Male, Female
(1998) ran to 53 pages.
(2)
Currently, the best short account of the state of knowledge is Steven Pinker’s
chapter on gender in The Blank Slate (2002).
(3)
Turning to race, we must begin
with the fraught question of whether it even exists, or whether it is instead a
social construct. The Harvard geneticist
Richard Lewontin
[ and Ashkenazi Jew - Editor ] originated the idea of
race as a social construct in 1972, arguing that the genetic differences across
races were so trivial that no scientist working exclusively with genetic data
would sort people into blacks, whites, or Asians. In his words, “racial
classification is now seen to be of virtually no genetic or taxonomic
significance.”
(25)
Elites throughout the West are
living a lie, basing the futures of their societies on the assumption that all
groups of people are equal in all respects. Lie is a strong word, but
justified. It is a lie because so many elite politicians who profess to believe
it in public do not believe it in private. It is a lie because so many elite
scholars choose to ignore what is already known and choose not to inquire into
what they suspect. We enable ourselves to continue to live the lie by
establishing a taboo against discussion of group differences.
Notes
Bibliography