The Bell Curve

September 23, 2011 § Leave a comment

The Bell Curve is a social science book on “intelligence and class structure in American life,” by Richard Herrnstein and Charles Murray. It was the subject of much controversy upon its publication in 1994.

No part of The Bell Curve received more attention than Chapter 13, on “Ethnic Differences in Cognitive Ability.”  It is from this chapter that I have taken the most quotations. Unlike this blog, The Bell Curve is not about race, and many interesting passages cannot be quoted without undermining the purpose of this blog.

My copy of this book, bought at Powell’s Books in Portland, is unmarked except for the infamous Chapter 13, where a cryptic “Who’s tests?” is written opposite its first page, and Chapters 4 and 5, which are about cognitive partitioning in education and employment. The following paragraph has been bracketed, with one word written in the outer margin: “ANGER”:

The United States is still very far from [perfect equality] at the extremes. If one thinks of babies growing up in slums with crack-addicted mothers, at one extreme, compared to children growing up in affluent, culturally rich homes with parents dedicated to squeezing every last IQ point out of them, then even a heritability of .6 leaves room for considerable change if the changes in environment are commensurably large…But those are, by definition, the extremes, the two tails of the distribution of environments. Moving a child from an environment that is the very worst to the very best may make a big difference. In reality, what most interventions accomplish is to move children from awful environments to ones that are merely below average, and such changes are limited in their potential consequences when heritability so constrains the limits of environmental effects. (109)

My edition was printed in 1996. When this comment was written, and by whom, is anyone’s guess. “ANGER” is a common reaction to this book. These quotes may help the reader decide if this anger is justified.

Nothing seems more fearsome to many commentators than the possibility that ethnic and race differences have any genetic component at all. This belief is a fundamental error. Even if the differences between races were entirely genetic (which they surely are not), it should make no practical difference in how individuals deal with each other. The real danger is that the elite wisdom on ethnic differences––that such differences cannot exist––will shift to opposite and equally unjustified extremes. Open and informed discussion is the one certain way to protect society from the dangers of one extreme view or the other. (270)

Ethnic differences in measured cognitive ability have been found since intelligent tests were invented. The battle over the meaning of these differences is largely responsible for today’s controversy over intelligence testing itself. (270)

There are differences between races, and they are the rule, not the exception…Races are by definition groups of people who differ in characteristic ways. Intellectual fashion has dictated that all differences must be denied except the absolutely undeniable differences in appearance, but nothing in biology says this should be so. (272)

Recall first that the American black population numbers more than 30 million people. If the results from the NLSY apply to the total black population…around 100,000 blacks fall into Class I of our five cognitive classes, with IQs of 125 or higher. (278)

External evidence of bias [in IQ tests] has been sought in hundreds of studies…Overwhelmingly, the evidence is that the major standardized tests used to help make school and job decisions do not underpredict black performance, nor does the expert community find any other general or systematic difference in the predictive accuracy of tests for blacks and whites. (281)

[The black-white IQ gap] is wider on items that appear to be culturally neutral than on items that appear to be culturally loaded. (282)

All [Gould’s ideas about race] can be true, and yet people who call themselves Japanese or Xhosa or Caucasians or Maori can still differ intellectually for genetic reasons. We may call them “ethnic groups” instead of races if we wish…but some ethnic groups nonetheless differ genetically for sure, otherwise they would not have differing skin colors or hair textures or muscle mass. They also differ intellectually on average. The question remaining is whether the intellectual differences overlap the genetic differences to any extent. (296-7)

It seems highly likely to us that both genes and the environment have something to do with racial differences. What might the mix be? We are resolutely agnostic on the issue; as far as we can determine, the evidence does not yet justify an estimate. (311)

It is possible to face all the facts on ethnic and race differences and not run screaming from the room. (315)

Much of the attack on The Bell Curve  has a purpose that occasionally has been stated explicitly, but more often tacitly: somehow, to put the genie back in the bottle, quelling discussion of topics that the book brought into the open…The trouble with this strategy is that it will backfire. My proposition is that the critics of The Bell Curve are going to produce the very effects that their attacks have been intended to avert. (556-7)


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You are currently reading The Bell Curve at Great Minds on Race.


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