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Review of The Bell Curve (Scarr) (fwd)
Ken JACOBS (jacobsk@ERE.UMONTREAL.CA)
Thu, 24 Nov 1994 11:05:48 -0500
The following is a `forward of a forward' so please take the time to read
it carefully enough to know to whom you should address your comments (if
any). It was written by Sandra Scarr <ss9v@fermi.clas.virginia.edu>, not
by Daniel Perusse (who forwarded it to HBES-L) or by me. Therefore, if you
have a comment, address it to the author in a separately sent message. DO NOT
use the reply function on your mailer.
Thank you.
-Ken Jacobs
Forwarded message:
> From owner-hbes-l@ARIZVM1.CCIT.ARIZONA.EDU Thu Nov 24 10:50:18 1994
> Message-Id: <199411241550.AA24547@condor.CC.UMontreal.CA>
> X-Delivery-Notice: SMTP MAIL FROM does not correspond to sender.
> Date: Thu, 24 Nov 1994 10:37:58 -0500
> Reply-To: Human Behavior & Evolution Society <HBES-L@ARIZVM1.BITNET>
> Sender: Human Behavior & Evolution Society <HBES-L@ARIZVM1.BITNET>
> From: Perusse Daniel <perussed@ERE.UMontreal.CA>
> Subject: Review of The Bell Curve (Scarr) (fwd)
> To: Multiple recipients of list HBES-L <HBES-L@ARIZVM1.BITNET>
>
> Following is what seems to me one of the most dispasionnate reviews of The
> Bell Curve written by one of the few reviewers who actually was active
> in collecting hard data relevant to the issue. Of special interest,
> perhaps, is Scarr's comment on her own study of IQ and African ancestry.
> This review was posted recently on the Behavior Genetic Association Network
> (BGANET) and might have escaped the attention of HBESers.
>
> Daniel Perusse
>
> (I "edited" the text only to avoid loss of words at the end of lines.
> Some more editing might be necessary on your own computers.)
>
>
> Forwarded message:
> > From bganet@lists.colorado.edu Mon Nov 21 18:04:55 1994
> > Date: Mon, 21 Nov 1994 16:00:46 -0700
> > Message-Id: <199411212255.PAA09592@alpha.Colorado.EDU>
> > Errors-To: stacey.cherny@colorado.edu
> > Reply-To: bganet@lists.colorado.edu
> > Originator: bganet@lists.colorado.edu
> > Sender: bganet@lists.colorado.edu
> > Precedence: bulk
> > From: Sandra Scarr <ss9v@fermi.clas.virginia.edu>
> > To: Multiple recipients of list <bganet@lists.colorado.edu>
> > Subject: Review of The Bell Curve (Scarr)
> > X-Listprocessor-Version: 6.0c -- ListProcessor by Anastasios Kotsikonas
> > X-Comment: BBoard for the Members of BGA
> >
> > To BGAnet:
> >
> > Delete now, if you are not interested in reading a 2,200 word review of
> > this book.
> >
> > >>
> Human Differences and Political Equality: The Dilemma of Group Differences in
IQ
>
> The Bell Curve: Intelligence and Class Structure in American Life, by Richard
> J. Herrnstein and
> Charles Murray. New York: Free Press, 1994, 845 pp.
> > >>
> > >> Sandra Scarr
> > >>
> > >>
> > >>
> > >> Issues in Science and Technology, in press.
> > >>
> > >>
> Sandra Scarr is Commonwealth Professor of Psychology at the University of
> Virginia
>
> Human Differences and Political Equality: The Dilemma of Group Differences in
IQ
> > >>
> The Bell Curve: Intelligence and Class Structure in American Life, by Richard
J.
> Herrnstein and
> > >> Charles Murray. New York: Free Press, 1994, 845 pp.
> > >>
> > >> Sandra Scarr "All men are created equal" is a political statement, not a
> scientific one. Individual variability
> > >> is the biological norm of populations. Humans are no exception.
> The Constitution guarantees
> > >> Americans political and legal equality, not biological identity.
> Confusion in the media and among
> > >> scholars about the fundamental difference between equal citizenship
> rights and unequal human
> > >> characteristics is behind much of the furor this book has aroused.
> > >> The Bell Curve is both an optimistically American story of a rising
> intellectual meritocracy
> > >> and a pessimistic tale of a cognitive underclass, doomed by low
> intelligence to high rates of crime,
> > >> school dropout, unwed births, welfare dependency, and poor parenting.
> The authors show that ,
> > >> for the past 50 years, selection into Cognitively Elite universities and
> high-status, well-paid
> > >> occupations has increasingly reflected high IQ rather than privileged
> family background. Similarly,
> > >> low socioeconomic status and social problems have increasingly become
> associated with low IQ
> > >> rather than low social status of one's parents.
> > >> When individuals' socioeconomic outcomes are shown to be affected
> by their own abilities,
> > >> most scholars and laypersons accept the scientific results. After all,
> America was built on
> > >> individual talents and initiative, or so we believe. Clearly, people
> differ in their abilities to cope with
> > >> educational, social, and occupational demands. The further information
> that IQ differences are
> > >> moderately to highly heritable is disturbing to some social scientists,
> but most Americans accept
> > >> the idea that individual differences in talents, motivation, and
> personality are genetically variable to
> > >> some degree.
> > >> Research on white North American and European populations shows that
> IQ differences are
> > >> 60 to 80% due to genetic variability and 15 to 35% to differences in
> rearing environments.
> > >> Surprisingly, most environmental variation related to intellectual
> differences comes from individual
> > >> experiences , rather than from opportunities provided by one family or
> another (5% is measurement
> > >> error). In a society with equal opportunities to learn, the heritability
> of IQ would approach 1.00,
> > >> because there would be no arbitrary environmental differences among
> individuals. If there are no
> > >> environmental differences in opportunities to learn, then all individual
> differences in IQ must arise
> > >> from genetic differences. High heritability can be seen as an index of
> social justice. Motivation and
> > >> personality are about 50% heritable, with the rest of the reliable
> variation due to within-family
> > >> environmental differences. The book's discussion of IQ heritability
> among whites is a fair summary
> > >> of behavior genetic research over the past 40 years.
> > >> A more disturbing dilemma arises for the body politic when
> individual differences in IQ
> > >> aggregate into ethnic or racial group differences, especially when those
> group differences in
> > >> intelligence have important real-life implications. A long history of
> racial discrimination tarnishes
> > >> U.S. claims of equal opportunity and clouds the book's overly simple
> treatment of African-
> > >> American's lower IQ scores and achievements. Further, the ugly
> political mood of the country
> > >> makes it unlikely that scientific studies of race differences will be
> calmly received.
>
> > >> Structure of the Book
> > >> Like Gaul, The Bell Curve is divided into three parts: scientific
> research on IQ and social
> > >> outcomes, IQ differences among ethnic groups and their social
> consequences, and social policies
> > >> the politically libertarian authors promote to address the social facts
> they identify. Everyone who
> > >> has read newspaper accounts or seen television reports will tell you that
> The Bell Curve is about
> > >> race and IQ, but it is not primarily so.
> > >> Part 1, the Science of IQ and Achievement. The Bell Curve is mostly
> about the increasing
> > >> relationship across the past 50 years between high intelligence and many
> forms of success in
> > >> America and the hidden role of low IQ in many forms of social pathology.
> Intelligence matters in
> > >> earning a place in society, whether intelligence is measured by IQ tests,
> SATs, the Armed Forces
> > >> Qualification Test, or school achievement tests. Rather than debate the
> concept of intelligence
> > >> (one factor or more), the authors adopt the theory and measurement of
> general intelligence, or "g",
> > >> which has proved exceedingly useful in studies of intellectually varied
> populations, such as
> > >> selection for training in varied military occupations. Within more
> narrowly defined intellectual
> > >> groups (e.g., Yale freshmen, corporation executives), measures other than
> IQ may prove useful to
> > >> predict success, because the whole group is so highly selected on general
> intelligence there is little
> > >> variability in "g".
> > >> The two tails of the normal IQ distribution represent extremes in
> both intelligence and social
> > >> adaptation. Using the large data set, known as the National
> Longitudinal Survey of Youth (NLSY),
> > >> the authors analyze the progress of some 9,000 white youths over 15
> years into adulthood. IQ
> > >> scores below 85 (1 standard deviation below the white mean of 100)
> predict poor outcomes,
> > >> including school dropout, unemployment, crime, welfare dependency, unwed
> births, low birth
> > >> weight infants, and poor parenting. The cognitive underclass, the
> authors predict, will be loathed
> > >> and feared by a society sick of crime and social problems. It is not a
> pretty picture.
> > >> Furthermore, the cognitive underclass is outbreeding Americans of
> average to high IQ. The
> > >> authors foresee the dumbing of America, through differential breeding of
> lower IQ citizens and
> > >> admission of immigrants with lower abilities. Data on birth rates to
> mothers of lower and higher IQs
> > >> confirm their premise. This information, combined with research
> showing that IQ is heritable and
> > >> research showing that low IQ mothers provide measurably poorer rearing
> environments for their
> > >> children, provides both genetic and environmental reasons for concern
> about this trend.
> > >> Today's Cognitive Elite, who attend the nation's most prestigious
> universities and enter the
> > >> professions, sciences, academia, and top corporate management, are less
> often descendants of
> > >> wealthy families and more often the brightest kids on whatever blocks
> they grew up on. Herrnstein
> > >> and Murray estimate that intellectually demanding professions now absorb
> nearly all high IQ white
> > >> Americans, leaving fewer bright workers in manual trades today than in
> earlier decades. The
> > >> authors fear that today's Cognitive Elite is becoming progressively more
> isolated from the rest of
> > >> society, whom they govern, hire and fire, but never live among. The
> isolation of the Cognitive Elite
> > >> begins early with public school tracking and ends with theCognitvie Elite
> sending their own children
> > >> to private schools.
> > >> The authors are properly skeptical about the effectiveness of
> educational interventions to
> > >> raise IQ. For children in very impoverished or abusive circumstances,
> educational enrichment can
> > >> raise cognitive functioning, but there is little evidence that current
> programs have any long-lasting
> > >> effects on IQ scores of children in adequate environments. Critics of
> heritability studies emphasize
> > >> that untried interventions could raise everyone's IQ (malleablity is
> unrelated to heritability, they
> > >> say), which is true for untried environments. Heritability does tell us
> that redistributing known
> > >> environments will have small effects on IQ differences. Educational
> achievements, however, can be
> > >> improved through better schooling and greater parental investments.
> Other countries do a better
> > >> job than we do at assuring nearly universal literacy and numeracy.
> > >> Part 2, Group Differences in IQ. Race enters the meritocratic
> picture because African-
> > >> Americans score, on average, 15 IQ points lower than whites, and IQ
> scores predict individuals'
> > >> social outcomes regardless of race. Whereas 20% of whites score below IQ
> 85, about 50% of
> > >> African-Americans do. Tests are not biased in the usual ways critics
> think. Because low IQ
> > >> segments of the white population have poor social outcomes, the much
> larger proportion of blacks
> > >> who score below IQ 85 is particularly disturbing. For unexplained
> reasons, the authors did not
> > >> conduct comparable analyses of the relationships of IQ to the Cognitive
> Elite or to social pathology
> > >> within the large black NLSY sample. Are African-Americans as efficiently
> selected into the
> > >> Cognitve Elite as are whites? Lower crrelations between IQ and social
> class among blacks suggest
> > >> not. Does low IQ have the same correlations with social pathology among
> African-Americans, or
> > >> are the correlations lower than those among whites? Because of
> affirmative action programs in
> > >> higher education and in employment, the authors show that at every level
> of college or university
> > >> and middle to high occupational levels, blacks' IQ scores fall below
> those of comparable whites by
> > >> at least a standard deviation. But less efficient selection for social
> mobility by IQ within the
> > >> African-American population would mean that, unlike whites, some high IQ
> African-Americans
> > >> remain in low status occupations.
> > >> On causes of between-race differences in IQ, the authors favor a
> mixture of genetic and
> > >> environmental differences as the most likely explanation. Although they
> admit that no research on
> > >> race differences in IQ is conclusive, they interpret the Minnesota study
> of transracial adoption as
> > >> support for their position. In this study, Richard Weinberg and I found
> that socially-identified black
> > >> children, who were adopted in infancy and early preschool years by middle
> class white families,
> > >> scored as well as white adoptees and well above average for
> African-Americans when they were an
> > >> average age of seven years. Some black adoptees had two African-American
> birth parents, while
> > >> others had one black and one white or Asian birth parent. At the
> average age of 18 years, their IQ
> > >> scores were lower than those of white and Asian adoptees in the same
> families. Adoptees with
> > >> two African-American birth parents earned IQ scores that were not notably
> higher than IQ scores of
> > >> black children reared in black families. The results of the transracial
> adoption study do not reject
> > >> either a social discrimination or a racial genetic difference hypothesis,
> because the low scores of
> > >> the black adoptees could be due to either, or both.
> > >> The authors fail to address evidence against a racial genetic
> difference hypothesis from our
> > >> study of IQ and African ancestry within a large sample of black
> adolescents. All of the children
> > >> were socially classified as black but differed individually in their
> proportion of African ancestry. We
> > >> found no relationship between blood group and serum protein markers of
> African ancestry and
> > >> cognitive test scores. If more African ancestry is not related to lower
> scores among socially-
> > >> classified blacks, then African ancestry can hardly be an explanation for
> IQ differences between
> > >> black and white groups. The authors also fail to address evidence for
> lower heritability of IQ scores
> > >> within a large sample of black identical and fraternal twins, which
> suggests that environments are
> > >> less equally distributed among blacks than among whites.
> > >> Latinos and Asians play only minor roles in press accounts, but
> major roles in the book.
> > >> Both groups score higher on tests than blacks and have better social
> outcomes, in keeping with the
> > >> authors' thesis about an IQ-social pathology link. In the NLSY data
> set, Latinos score lower on
> > >> ability tests and have higher rates of social pathology than whites, but
> higher scores and lower
> > >> rates than blacks. Asians were not sampled in significant numbers in the
> NLSY, but other research
> > >> shows them to have an equal or higher average IQs than whites, and very
> low rates of social
> > >> pathology.
> > >> Part 3, Social Policy Proposals. The authors' solutions to the
> social and economic
> > >> consequences of low intelligence are to cut off welfare and affirmative
> action and to admonish
> > >> everyone to find a "valued place" in his or her "clan" or local
> community. The authors' eugenic
> > >> concerns are addressed by public policies that would eliminate incentives
> for poor, unwed mothers
> > >> to reproduce.
> > >> Charles Murray did not need the scientific literature on individual
> and group differences in
> > >> intelligence and achievement to propose the abolition of welfare supports
> to single mothers or the
> > >> abolition of affirmative action for African-Americans. He had already
> proposed those policies to a
> > >> skeptical Congress many years ago. Data on the correlates of
> intellectual variation in the U.S.
> > >> population do nothing to further his case. Rather, since the 1980s,
> Murray has argued that serious
> > >> economic costs are associated with forcing selection of unqualified
> minority candidates in higher
> > >> education and employment (i.e., higher training costs and lower
> productivity). Further, selection of
> > >> less qualified minorites cheapens the achievments of those
> African-Americans, whose qualifications
> > >> are equal or superior to those of whites.
> > >> Even the authors do not suggest that their public policy proposals
> arise from the scientific
> > >> data. In fact, one could argue that knowing that low IQ is largely
> heritable calls for more, not less
> > >> support for those so disadvantaged through no fault of their own. Low
> IQs reduce individuals'
> > >> chances to be fully self-sufficient in a technological society;
> therefore, compensation for low IQ is
> > >> a plausible American policy. Compensation for disabilities derives from
> our concerns with social
> > >> justice for those whose disadvantages are not their fault. Social
> welfare democracies (e.g., the
> > >> European Union and the Nordic Countries) have the same IQ distribution as
> the U.S., yet their
> > >> public policies prevent abject poverty, homelessness, and medical
> neglect among those with low
> > >> IQs. A "valued place" is hard to build on hunger, poverty, and despair.
> > >> Justifying affirmative action programs that select and promote less
> qualified minorities over
> > >> higher IQ whites depends entirely on the value society attaches to ethnic
> diversity in educational
> > >> and employment settings. If assuring African-Americans "valued places"
> throughout American
> > >> society has a high value, then selection models can be devised to make
> that happen. Scientific
> > >> research on race differences in IQ scores can inform us about how to
> carry out that policy, but
> > >> science cannot define the values that make ethnic diversity important.
> Policies proposed in the
> > >> book favor economic efficiency over social harmony.
> > >> The Bell Curve is a challenging book that compiles a vast research
> literature on IQ and
> > >> social outcomes and spells out the troubling facts on ethnic group
> differences. Because of the
> > >> authors' radical proposals to abolish welfare and affirmative action,
> however, otherwise rational
> > >> scientists and policymakers will be tempted to dismiss the very data that
> could inform more benign
> > >> and effective public programs to address the needs of low IQ Americans.
> >
>
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