Greetings!
I found this
on the web yesterday, and I'm totally confused.
I wonder if
all of these professors are mistaken or they just don't like black
people. What
do you think?
Racial Differences in Intelligence: What Mainstream Science Says
This public statement,
signed by 52 internationally known scholars, was active
on the information
highway early in 1995 following several rather heated and
negative responses
to Herrnstein & Murray's The Bell Curve. It was first
published in
The Wall Street Journal, Tuesday, December 13, 1994. An
alphabetical
listing of the scholars and their home institutions are given at
the end of the
statement.
Prologue
Since the publication
of "The BELL CURVE," many commentators have offered
opinions about
human intelligence that misstate current scientific evidence.
Some conclusions
dismissed in the media as discredited are actually firmly
supported.
This statement
outlines conclusions regarded as mainstream among researchers
on intelligence,
in particular, on the nature, origins, and practical
consequences
of individual and group differences in intelligence. Its aim is
to promote more
reasoned discussion of the vexing phenomenon that the research
has revealed
in recent decades. The following conclusions are fully described
in the major
textbooks, professional journals and encyclopedias in
intelligence.
The Meaning and Measurement of Intelligence
1.Intelligence
is a very general mental capability that, among other
things, involves
the ability to reason, plan, solve problems, think
abstractly,
comprehend complex ideas, learn quickly and learn from experience.
It is not merely
book learning, a narrow academic skill, or test-taking
smarts. Rather,
it reflects a broader and deeper capability for comprehending
our surroundings
-- "catching on," "making sense" of things, or "figuring out"
what to do.
2.Intelligence,
so defined, can be measured, and intelligence tests
measure it well.
They are among the most accurate (in technical terms,
reliable and
valid) of all psychological tests and assessments. They do not
measure creativity,
character, personality, or other important differences
among individuals,
nor are they intended to.
3.While there
are different types of intelligence tests, they all
measure the
same intelligence. Some use words or numbers and require specific
cultural knowledge
(like vocabulary). Others do not, and instead use shapes or
designs and
require knowledge of only simple, universal concepts (many/few,
open/closed,
up/down).
4.The spread
of people along the IQ continuum, from low to high, can be
represented
well by the BELL CURVE (in statistical jargon, the "normal
CURVE"). Most
people cluster around the average (IQ 100). Few are either very
bright or very
dull: About 3% of Americans score above IQ 130 (often
considered the
threshold for "giftedness"), with about the same percentage
below IQ 70
(IQ 70-75 often being considered the threshold for mental
retardation).
5.Intelligence
tests are not culturally biased against American blacks
or other native-born,
English-speaking peoples in the U.S. Rather, IQ scores
predict equally
accurately for all such Americans, regardless of race and
social class.
Individuals who do not understand English well can be given
either a nonverbal
test or one in their native language. 6.The brain processes
underlying intelligence
are still little understood. Current research looks,
for example,
at speed of neural transmission, glucose (energy) uptake, and
electrical activity
of the brain.
Group Differences
1.Members of
all racial-ethnic groups can be found at every IQ level..
The BELL CURVES
of different groups overlap considerably, but groups often
differ in where
their members tend to cluster along the IQ line. The BELL
CURVES for some
groups (Jews and East Asians) are centered somewhat higher
than for whites
in general. Other groups (blacks and Hispanics) are centered
somewhat lower
than non-Hispanic whites.
2.The BELL CURVE
for whites is centered roughly around IQ 100; the BELL
CURVE for American
blacks roughly around 85; and those for different subgroups
of Hispanics
roughly midway between those for whites and blacks. The evidence
is less definitive
for exactly where above IQ 100 the BELL CURVES for Jews and
Asians are centered.
Practical Importance
1.IQ is strongly
related, probably more so than any other single
measurable human
trait, to many important educational, occupational, economic,
and social outcomes.
Its relation to the welfare and performance of
individuals
is very strong in some arenas in life (education, military
training), moderate
but robust in others (social competence), and modest but
consistent in
others (law-abidingness). Whatever IQ tests measure, it is of
great practical
and social importance.
2.A high IQ
is an advantage in life because virtually all activities
require some
reasoning and decision-making. Conversely, a low IQ is often a
disadvantage,
especially in disorganized environments. Of course, a high IQ no
more guarantees
success than a low IQ guarantees failure in life. There are
many exceptions,
but the odds for success in our society greatly favor
individuals
with higher IQs.
3.The practical
advantages of having a higher IQ increase as life
settings become
more complex (novel, ambiguous, changing, unpredictable, or
multi-faceted).
For example, a high IQ is generally necessary to perform well
in highly complex
or fluid jobs (the professions, management); it is a
considerable
advantage in moderately complex jobs (crafts, clerical and police
work); but it
provides less advantage in settings that require only routine
decision making
or simple problem solving (unskilled work).
4.Differences
in intelligence certainly are not the only factor
affecting performance
in education, training, and highly complex jobs (no one
claims they
are), but intelligence is often the most important. When
individuals
have already been selected for high (or low) intelligence and so
do not differ
as much in IQ, as in graduate school (or special education),
other influences
on performance loom larger in comparison.
5.Certain personality
traits, special talents, aptitudes, physical
capabilities,
experience, and the like are important (sometimes essential) for
successful performance
in many jobs, but they have narrower (or unknown)
applicability
or "transferability" across tasks and settings compared with
general intelligence.
Some scholars choose to refer to these other human
traits as other
"intelligences."
Source and Stability of Within-Group Differences
1.Individuals
differ in intelligence due to differences in both
their environments
and genetic heritage. Heritability estimates range from 0.4
to 0.8 (on a
scale from 0 to 1), most thereby indicating that genetics plays a
bigger role
than does environment in creating IQ differences among
individuals.
(Heritability is the squared correlation of phenotype with
genotype.) If
all environments were to become equal for everyone, heritability
would rise to
100% because all remaining differences in IQ would necessarily
be genetic in
origin.
2.Members of
the same family also tend to differ substantially in
intelligence
(by an average of about 12 IQ points) for both genetic and
environmental
reasons. They differ genetically because biological brothers and
sisters share
exactly half their genes with each parent and, on the average,
only half with
each other. They also differ in IQ because they experience
different environments
within the same family.
3.That IQ may
be highly heritable does not mean that it is not
affected by
the environment. Individuals are not born with fixed, unchangeable
levels of intelligence
(no one claims they are). IQs do gradually stabilize
during childhood,
however, and generally change little thereafter.
4.Although the
environment is important in creating IQ
differences,
we do not know yet how to manipulate it to raise low IQs
permanently.
Whether recent attempts show promise is still a matter of
considerable
scientific debate. 5.Genetically caused differences are not
necessarily
irremediable (consider diabetes, poor vision, and phenal
ketonuria),
nor are environmentally caused ones necessarily remediable
(consider injuries,
poisons, severe neglect, and some diseases). Both may be
preventable
to some extent.
Source and Stability of Between-Group Differences
1.There is no
persuasive evidence that the IQ BELL CURVES for different
racial-ethnic
groups are converging. Surveys in some years show that gaps in
academic achievement
have narrowed a bit for some races, ages, school subjects
and skill levels,
but this picture seems too mixed to reflect a general shift
in IQ levels
themselves.
2.Racial-ethnic
differences in IQ BELL CURVES are essentially the same
when youngsters
leave high school as when they enter first grade. However,
because bright
youngsters learn faster than slow learners, these same IQ
differences
lead to growing disparities in amount learnedas youngsters
progress from
grades one to 12. As large national surveyscontinue to show,
black 17-year-olds
perform, on the average, more likewhite 13-year-olds in
reading, math,
and science, with Hispanics inbetween.
3.The reasons
that blacks differ among themselves in intelligence
appear to be
basically the same as those for why whites (or Asians
orHispanics)
differ among themselves. Both environment and geneticheredity are
involved.
4.There is no
definitive answer to why IQ bell curves differ
acrossracial-ethnic
groups. The reasons for these IQ differences betweengroups
may be markedly
different from the reasons for why individualsdiffer among
themselves within
any particular group (whites or blacks orAsians). In fact,
it is wrong
to assume, as many do, that the reason whysome individuals in a
population have
high IQs but others have low IQs must be the same reason why
some populations
contain more such high (or low) IQ individuals than others.
Most experts
believe that environment is important in pushing the bell curves
apart, but that
genetics could be involved too.
5.Racial-ethnic
differences are somewhat smaller but still substantial
for individuals
from the same socioeconomic backgrounds. To illustrate, black
students from
prosperous families tend to score higher in IQ than blacks from
poor families,
but they score no higher, on average, than whites from poor
families.
6.Almost all
Americans who identify themselves as black have white
ancestors --
the white admixture is about 20%, on average -- and many self-
designated whites,
Hispanics, and others likewise have mixed ancestry. Because
research on
intelligence relies on self-classification into distinct racial
categories,
as does most other social-science research, its findings likewise
relate to some
unclear mixture of social and biological distinctions among
groups (no one
claims otherwise). The average I.Q for African blacks was
found to be
75, the higher intelligence of American blacks is due to the
percentage of
white blood that is characteristic of American blacks.
Implications for Social Policy
1.The research
findings neither dictate nor preclude any particular social
policy, because
they can never determine our goals. They can, however, help us
estimate the
likely success and side-effects of pursuing those goals via
different means.
The following
professors -- all experts in intelligence and allied fields --
have signed
this statement:
•Richard D. Arvey,
University of Minnesota •Thomas J. Bouchard, Jr.,
University of
Minnesota •John B. Carroll, Un. of North Carolina at Chapel Hill
•Raymond B.
Cattell, University of Hawaii •David B. Cohen, University of Texas
at Austin •Rene
V. Dawis, University of Minnesota •Douglas K. Detterman, Case
Western Reserve
Un. •Marvin Dunnette, University of Minnesota •Hans Eysenck,
University of
London •Jack Feldman, Georgia Institute of Technology •Edwin A.
Fleishman, George
Mason University •Grover C. Gilmore, Case Western Reserve
University •Robert
A. Gordon, Johns Hopkins University •Linda S. Gottfredson,
University of
Delaware •Robert L. Greene, Case Western Reserve University
•Richard J.Haier,
University of Callifornia at Irvine •Garrett Hardin,
University of
California at Berkeley •Robert Hogan, University of Tulsa
•Joseph M. Horn,
University of Texas at Austin •Lloyd G. Humphreys, University
of Illinois
at Urbana-Champaign •John E. Hunter, Michigan State University
•Seymour W.
Itzkoff, Smith College •Douglas N. Jackson, Un. of Western Ontario
•James J. Jenkins,
University of South Florida •Arthur R. Jensen, University
of California
at Berkeley •Alan S. Kaufman, University of Alabama •Nadeen L.
Kaufman, California
School of Professional Psychology at San Diego •Timothy Z.
Keith, Alfred
University •Nadine Lambert, University of California at Berkeley
•John C. Loehlin,
University of Texas at Austin •David Lubinski, Iowa State
University •David
T. Lykken, University of Minnesota •Richard Lynn, University
of Ulster at
Coleraine •Paul E. Meehl, University of Minnesota •R. Travis
Osborne, University
of Georgia •Robert Perloff, University of Pittsburgh
•Robert Plomin,
Institute of Psychiatry, London •Cecil R. Reynolds, Texas A &
M University
•David C. Rowe, University of Arizona •J. Philippe Rushton, Un.
of Western Ontario
•Vincent Sarich, University of California at Berkeley
•Sandra Scarr,
University of Virginia •Frank L. Schmidt, University of Iowa
•Lyle F. Schoenfeldt,
Texas A & M University •James C. Sharf, George
Washington University
•Herman Spitz, former director E.R. Johnstone Training
and Research
Center, Bordentown, N.J. •Julian C. Stanley, Johns Hopkins
University •Del
Thiessen, University of Texas at Austin •Lee A. Thompson, Case
Western Reserve
University •Robert M. Thorndike, Western Washington Un.
•Philip Anthony
Vernon, Un. of Western Ontario •Lee Willerman, University of
Texas at Austin