The life of a diversicrat is disagreeable. He is surrounded by irritants. Of
them, he finds none more unsettling than race, particularly racial
differences. He confronts them daily, on the athletic field, in the
classroom, in the workplace and on the street. Most prickly are IQ
differences. Intelligence, after all, is the hallmark of our species. The
diversicrat twists and strains to explain IQ gaps away, abandoning parsimony
for convolution. But he does not stop with explication. He is an ideological
crusader. And like most crusades, this one has victims. Sadly, they include
the ill-starred and hapless mentally retarded. Their wretched malady is
secondary to the fact that they are asymmetrically black.
  Nature-nurture issues do not concern us here. We ask how, not why. We
accept racial IQ incongruities as facts, noting only that efforts to erase
them have failed. The average IQ of East Asians (Chinese, Japanese and
Koreans) is about 1/3 standard deviation (SD) or about 5 IQ points higher
than that of Europeans. Ashkenazic Jews score higher still. Their mean IQ is
about 15 IQ points above that of non-Hispanic whites. In the US, the African
American with a mean score of 85 is at the bottom of the cognitive deck. He
thus finds himself disproportionately represented among the ranks of the
retarded. All this is anathema to the diversicrat.

  The black-white IQ gap has been studied and analyzed for more than 80
years. It has outlived sweeping attitude changes, from extreme anti-black
discrimination to bias against whites, Asians and males. The billion-dollar
Head Start budget has not dented it. Though IQ scores have been rising
worldwide for decades (the Flynn effect) the cognitive distance between
blacks and whites has remained remarkably constant. In fact, the 1 SD
black-white IQ gap is as close to a fundamental sociological constant as we
come.

  When the IQ of non-Hispanic whites is normalized to a mean of 100 and SD
of 15, the African American mean falls at about 85 with an SD of about 13.5.
The black IQ distribution both lags behind and is narrower than the white.
The small difference in width manifests itself significantly at the bell
curve extremes, reducing both the numbers of retarded and exceptional
blacks.

  Figure 1 shows IQ distribution curves for African Americans and
non-Hispanic whites. The areas under the curves are normalized to unity, so
that the narrower black distribution appears taller. Two standard deviations
from each side of the white mean mark IQ boundaries for retardation and
giftedness. Outside these borders, in the shaded regions, are the cognitive
extremes. There, the areas under the curves represent the fractions of each
group who meet IQ criteria for retardation or giftedness. (Most striking is
the tiny black representation in the gifted region.) The ratio of areas
shows blacks to be 6.1 times more likely than whites to fall below the
boundary for retardation, and 53 times less likely to be gifted. So profound
are the group differences that they are apparent to the man in the street,
who observes a profusion of African Americans at the bottom of the economic
and educational ladders, and a scarcity at the top.