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Clever Arguments, Atrocious Science




Intelligence and Class Structure in American Life

By Richard J. Herrnstein and Charles Murray

Free Press 845pp $30

At the core of the American psyche is the belief that hard work, education, and perseverance can overcome any disadvantage of wealth, background, or class. It may even be true. The history of the U.S. is filled with individuals rising from rural poverty or immigrant ghettos to gain affluence, political power, or Nobel prizes.

These successes are even more striking given the public prejudices arrayed against many of these people. After the great wave of immigration from eastern and southern Europe in the early 1900s, for instance, a Denver Post columnist warned that New York City had become "a cesspool" of "immigrant trash." Social scientists "proved" that the new Americans, many of them Jewish, would drag down the nation's average intelligence, since they scored lower on IQ tests.

But a funny thing happened on the way to the future. Within decades, the "trash" was not only rising through society but also was showing remarkable gains in the supposedly fixed measure of IQ. In fact, Jews now score some 10 points higher than the white average.

Consider another group of "new" Americans, the newly freed blacks of the late 1800s. Historians say they shared the immigrants' belief in education as the path to advancement. By World War I, Northern blacks were outscoring Southern whites on Army IQ tests. Haverford College's Roger Lane has found that black literacy rates in Philadelphia quadrupled in the 1890s. Rising achievement led to blacks' first major political demand--that the city award jobs based on written exams.

But even though blacks performed better than white rivals on the tests, achievement didn't open doors. Philadelphia refused to hire accordingly, leaving "trained black doctors working as bell-hops," says Lane. "As a result, the hunger for education got beaten out."

These facts are only hinted at in The Bell Curve, the controversial new book by conservative American Enterprise Institute Fellow Charles Murray and late Harvard psychologist Richard J. Herrnstein. The authors admit "immigrants have sometimes shown large increases" in IQ, and that a lack of education can cause poor test performance. But their thesis is exactly the opposite: IQ scores, they say, are largely immutable and represent innate intelligence.

The ranks of the cognitively inferior, they assert, are disproportionately filled with blacks, Latinos, and today's immigrants. And that's a serious disadvantage, because low IQ--not education or opportunity--is the key factor underlying problems ranging from poverty and criminal behavior to out-of-wedlock births and being a bad parent. "Success and failure...are increasingly a matter of the genes that people inherit," the authors warn. That people can get ahead by plain hard work is "no longer true."

Worse, they add, growth of the dumb population may already be dragging America down. All of this is "uncomfortable" truth that the authors purport to be bravely revealing. To deny it, they say, is to cave in to political correctness.

There are grains of truth--and much cleverness--in this argument. People differ in a wide range of talents and abilities, and being smart is unquestionably an advantage. Moreover, the authors deserve credit for venturing provocative statements about social problems. They argue persuasively that many schools fail to challenge students, that affirmative action has undermined the perceived legitimacy of college degrees for minorities, and that America is increasingly split between haves and have-nots.

But The Bell Curve's message--that IQ is destiny--is not just politically incorrect, it's a breathtakingly wrongheaded interpretation of the underlying science. In fact, there's a grim sport for sharp-eyed readers in spotting the weak links, misrepresentations, and logical inconsistencies that riddle the supposedly objective analysis of the data.

Consider the book's assertion that IQ scores reflect fundamental cognitive ability and can be equated with "maturity...and personal competence." That's a huge reach. A number of social scientists, brusquely dismissed by the authors, say intelligence is many-faceted, and that IQ represents but one component. Yale's Robert J. Sternberg, for example, has constructed tests to measure "practical intelligence"--how well people deal with real-life situations. Scores on these tests predict job performance better than IQ tests--and scores don't differ among ethnic groups. What does IQ really represent? As the authors themselves point out, it seems to measure thinking speed.

Murray and Herrnstein forget to note other uncomfortable truths. Most of their key data come from a long-term study of some 12,000 people who once took an Armed Forces aptitude exam. But Pentagon scientists who administer it say the test isn't even an IQ test. Scores rise with the amount of schooling test-takers have, notes Bernard M. Baruch College's June O'Neill, who uses the test to study such issues as workplace discrimination. So it's no surprise that scores predict school performance.

Those who probe the statistics will find that many of the book's claims for the predictive power of IQ are dubious at best. If the average IQ of the U.S. drops just three points, the authors warn, poverty will jump 11%, crime 13%, and single motherhood 8%. But that assumes that all these measures change with every point difference in IQ. In fact, such negative outcomes rise only with increases in the number of people with very low scores--borderline retarded and below. Even then, they rise only modestly. For the vast majority, big differences in IQ lead to virtually no difference in such key measures as income. After all, the average IQ difference between any pair of siblings is 13 points, about the same as the black/white spread.

Even if we suspend reason and accept the book's belief in IQ, The Bell Curve founders on contradictions. Social scientists agree that IQ scores of all groups have risen some 15 points in the last 40 years--and the gap between whites and blacks has narrowed. So how can Murray and Herrnstein argue that growing social ills are partly caused by an increase in dumb folks? They admit that disadvantaged children adopted into more affluent and stable families can show big increases in IQ. So why do they insist IQs can rarely be changed? How can they say coaching doesn't raise scores over the long term, then dismiss a big long-term increase in a Milwaukee program as merely a product of coaching? And how can they denigrate the college degrees earned by blacks who matriculate despite lower SAT scores without saying that whites with the same SAT scores--the disadvantaged, perhaps, or children of alumni--are equally undeserving?

What's more, when it comes to key facts such as the high rate of blacks on welfare, the authors have to admit IQ isn't the explanation. They concede, for example, that data suggest "that blacks differ from whites or Latinos in their likelihood of being on welfare for reasons that transcend both poverty and IQ."

There are two inescapable conclusions. One is that IQ scores are not destiny, especially for the vast majority of us--of whatever color--who are not retarded. The other is that The Bell Curve is a house of cards constructed to push a political agenda--an attack on affirmative action, the welfare system, and schools that fail the gifted. Those views deserve airing. As Herrnstein and Murray argue, a forthright discussion of these issues might even lead to better social policy.

But to couch their opinions as scientific truth is downright dangerous. The Bell Curve could trigger insidious discriminapion. A century ago, doors closed on people striving for a better life just because of the color of their skin. Now, the slamming will be justified on the grounds of lower intelligence. That's not the kind of America we want to create.JOHN CAREY


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