[This is an important paper by Rushton who is an expert on human intelligence. He and Lynn in the UK are very important scientists in this field. Lynn is actually fantastic. He is a real pioneer in this field. Rushton writes a paper that basically tackles some garbage that is being put out there. The garbage is that White/Black IQs are narrowing. If this were true it would be terrible news for Whites. But thank goodness it is NOT TRUE, and Rushton points this out. So I suspect it is the Jews, as usual, talking their Jew crap when it comes to race. Jews will do ANYTHING in order to befuddle Whites, and confuse us. Even when Jews know the truth, it is to me as if they deliberately, almost always, without fail, ENGAGE IN CREATING CONFUSION. Our race is constantly seeking the THREAT OF TRUTH SO AS TO FOLLOW IT and the Jews are confusing it like crazy. In this case, Jews are talking all kinds of bunk about IQ. For Jews, LYING IS A CRITICAL SURVIVAL STRATEGY. They have to lie. Not only in order to profit and move forward, but in fact even to just live. For them it is a case of lying every day of their existence, creating confusion, while stealing, tricking and cheating what they can, while they can. Truly. That is what their lives are about. For them, the real threat is that Whites might actually move forward and they need to confuse us, and block our path or else we'll be streaking ahead and they'll be losing. Jews of course will lie in any way. They will lie in science and in history. They'll lie about the future and they'll lie about today and they'll lie about history. That's the crux of their existence. We must remain firmly hooked on the TRUTH and the TRUTH ONLY. And Jews know that the TRUTH can DESTROY THEM … so they lie endlessly… Jan]


The University of Western Ontario

Arthur R. Jensen

University of California, Berkeley

Despite repeated claims to the contrary, there has been no narrowing of the 15- to
18-point average IQ difference between Blacks and Whites (1.1 standard devia-
tions); the differences are as large today as they were when first measured nearly
100 years ago. They, and the concomitant difference in standard of living, level of
education, and related phenomena, lie in factors that are largely heritable, not
cultural. The IQ differences are attributable to differences in brain size more than to
racism, stereotype threat, item selection on tests, and all the other suggestions given
by the commentators. It is time to meet reality. It is time to stop committing the
“moralistic fallacy” that good science must conform to approved outcomes.
In our target article (Rushton & Jensen, 2005), we proposed a hereditarian
model—50% genetic–50% environmental—to explain the 15- to 18-point average
IQ difference (1.1 standard deviations) between Blacks and Whites. We reviewed
the worldwide distribution of test scores, the g factor of mental ability, the
heritability of within- and between-groups differences, the relation of brain size to
intelligence and of race differences in brain size, regression to the mean, cross-
racial adoption studies, racial admixture studies, and data from life-history traits
and human origins research. We were unable to identify (in Section 12 of Rushton
& Jensen, 2005) any reliable environmental contribution to the Black–White IQ
difference, including the non-g Flynn effect (i.e., the secular rise in IQ scores). We
also found that on many dimensions, East Asian–White differences were a mirror
image of Black–White differences. In Section 14, we concluded in favor of an
even stronger hereditarian model— 80% genetic–20% environmental— based on
Jensen’s (1998, p. 443) “default hypothesis” that, by adulthood, genetic and
environmental factors carry the same weight in causing group differences as they
do in causing individual differences.

Gottfredson (2005) is the only commentator who confronted head-on all the
empirical, theoretical, and moral issues. The other commentators (Nisbett, 2005;
Sternberg, 2005; Suzuki & Aronson, 2005) sidestepped the totality of the three-
way race– behavior matrix shown in our Table 3. They invoked one or other of the
culture-only refrains, that “race” is only “skin deep”; if not, then any difference
is too small to matter; if not, then it is due to cultural factors such as statistical
artifacts, insensitive tests, racism, stereotype threat, and poverty; if not, then it is
poor form to talk about it. They also offered the usual culture-only promissory
notes that the Black–White IQ gap can be reduced by economic improvements,
interventionist programs, culture-friendly assessment systems, and nonweighted
J. Philippe Rushton, Department of Psychology, The University of Western Ontario, London,
Ontario, Canada; Arthur R. Jensen, School of Education, University of California, Berkeley.
Correspondence concerning this article should be addressed to J. Philippe Rushton, Department
of Psychology, The University of Western Ontario, London, Ontario N6A 5C2, Canada. E-mail:

models of gene– environment interaction. Their examples only confirm what we
described in Sections 2, 13, and 14: Culture-only theory is a degenerating research

Are Black–White IQ Differences Narrowing?

Nisbett (2005) provided the most empirically forceful of the rebuttals. He
claimed that the Black–White IQ difference had decreased to only 10 points in
magnitude ( 0.70 standard deviations) and that it could be eliminated altogether
within 20 to 60 years. He based this assertion on a purported narrowing of the
Black–White difference on school achievement tests (reading, vocabulary, and
mathematics), which he then extrapolated to the IQ differences.

Reality, however, is stubborn. Jensen (1998, pp. 375–376, n. 33, 407– 408,
494 – 495) showed that gains in scholastic achievement do not equal gains in g,
and the Black–White differences in g are as large as ever, even for measures of
reaction time. Jensen’s conclusion dovetails with a meta-analysis by Roth, Bevier,
Bobko, Switzer, and Tyler (2001) that we cited at the opening of our target article.
They found a mean effect size of 1.1 standard deviations that ranged from 0.38 to
1.46 (based on a sample of 6,246,729 from corporate, military, and higher
education samples) depending on the g loading of the test. On the question of
whether the difference was diminishing, they suggested any reduction was “either
small, potentially a function of sampling error . . . or nonexistent for highly g
loaded instruments [italics added]” (Roth et al., 2001, p. 323).

In her commentary, Gottfredson (2005) underscored this message with evi-
dence that no narrowing had taken place in average Black–White differences. She
contrasted Black–White differences on highly g-loaded “IQ tests” with those on
less g-loaded “school achievement tests.” Gottfredson found that Black–White
differences on IQ tests remained constant at 1.0 standard deviation throughout the
20th century. She agreed that the differences on school achievement tests did
narrow slightly from 1.07 to 0.89 standard deviations from the 1970s to the 1990s
when the National Assessment of Educational Progress collected data on 9- to
17-year-olds. However, as she then pointed out, even this 20% reduction in
educational achievement (a) had occurred by the mid-1980s and no longer
continues, (b) is compatible with the group differences in g, and (c) does not
contradict the hereditarian hypothesis.

These variable Black–White differences are explained by Spearman’s (1927)
hypothesis, which states that Black–White IQ differences are “most marked in just
those [tests] which are known to be saturated with g” (p. 379; see Section 4 of
Rushton & Jensen, 2005). The differences are lower on specific tests of memory,
or arithmetic and spelling, than they are on general reasoning and transforming
information. One implication is that test constructors could in principle reduce the
Black–White difference to zero (or even reverse it) by including only non-g items
(or those negatively loaded on g). However, they would then be left with a test
that had little or no predictive power. Roth et al.’s (2001) meta-analysis con-
cluded: “Overall, the results for both industrial and educational samples provide
support for Spearman’s hypothesis. That is, black–white differences on measures
of cognitive ability tended to increase with the saturation of g in the measure of
ability” (Roth et al., 2001, p. 317).



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