IQ and Testing: Origin and Development

The first intelligence test was devised by French psychologist Alfred Binet (1857–1911) in Paris in 1905. The test, designed for schoolchildren, assessed both the child’s fund of acquired knowledge and academic skills. The child’s performance was compared to the typical performance of children of various ages. If children did as well as other children of the same age, they were labeled “normal.” If children did as well as older children, they were “bright.” If the child could only do as well as younger children, Binet concluded that their intelligence was not developing properly and they should receive remedial education. Binet prescribed courses of “mental orthopedics” for those who did poorly on his test. The test was thus to be used as a diagnostic instrument, indicating a possible need for corrective treatment. Binet did not regard the test as measuring some fixed, unchangeable capacity, however, and he railed against the “brutal pessimism” of those who might think otherwise.

Within a decade of Binet’s original work, adaptations of his test, including some designed for use with adults, were in use in the United States. The pioneers of the American mental testing movement (Henry Goddard [1866–1957], Lewis Terman [1877–1956], and Robert Yerkes [1876–1956]) all asserted that intelligence tests did measure a fixed, unchangeable capacity, largely determined by an individual’s heredity. Familial resemblance in IQ scores was claimed to be evidence of the role of heredity. In addition, racial differences in average IQ were erroneously seized upon as evidence of genetic superiority and inferiority.

In 1912 Henry Goddard administered supplemented Binet tests to European immigrants arriving at Ellis Island in New York harbor. He reported that 83 percent of Jews, 80 percent of Hungarians, 79 percent of Italians, and 87 percent of Russians were “feeble-minded.” Lewis Terman, who introduced the Stanford-Binet test to the United States, wrote that IQs in the 70–80 range, indicating borderline mental deficiency, were “very common among Spanish-Indian and Mexican families of the Southwest and also among negroes. Their dullness seems to be racial… . The writer predicts that … there will be discovered enormously significant racial differences which cannot be wiped out” (1916, pp. 91–92).

A claim was soon made that Terman’s prediction of racial differences had been verified. Robert Yerkes had been head of a massive program to administer specially developed IQ tests to draftees into the United States Army during World War I. Many of the draftees were foreign-born and either unfamiliar with the English language or illiterate in English. Yerkes and a committee of psychologists devised two “group tests” of intelligence. “Alpha” was a written test that could be administered to large groups. “Beta” was a “nonverbal” test designed for men either unfamiliar with English or illiterate. Instructions for Beta were given in pantomime to groups of soldiers.

After the war, in 1921, the National Academy of Sciences published an analysis, edited by Yerkes, of the data collected during the army’s testing program. This was the first large-scale demonstration that American blacks scored lower on IQ tests than whites. Given the stereotypes that prevailed at the time, however, that finding occasioned little surprise. The data with immediate political impact were the IQ scores of foreign-born draftees. The Yerkes report indicated that the immigrants with the highest scores came from England, Scandinavia, and Germany. The lowest scorers were immigrants from Russia, Italy, and Poland, whose average IQs were not perceptibly higher than that of native-born blacks. The Army findings were supported in a 1923 textbook by Rudolf Pintner, who indicated that the median IQ found in six studies of Italian children in America was only 84—as low as the average of American blacks.

In 1923 Carl Brigham published a re-analysis of the Army data, concluding that the tests had demonstrated “a genuine intellectual superiority of the Nordic group” over “Alpine and Mediterranean blood.” Yerkes, in a preface to Brigham’s book, stressed the relevance of the Army data to “the practical problems of immigration.” At the time, a flood of “New Immigration” from the “Alpine and Mediterranean” countries of southern and eastern Europe was replacing the earlier stream of immigrants from English-speaking and “Nordic” countries. Popular support for a new and restrictive immigration law was widespread. The Army data were cited repeatedly in Congressional debates that ended in the passage of a racist immigration law in 1924. The new law imposed “national origin quotas” on future immigration. The design and effect of the quotas was to reduce sharply the proportion of “Alpine and Mediterranean” immigrants.

Forty-five years later, racial differences in average IQ again came to the fore in a political context, but this time the genetically inferior groups were no longer Alpines and Mediterraneans—they were blacks. Arthur Jensen, in an influential and widely publicized review article published in 1969, maintained that efforts at compensatory education were doomed to failure. He argued that children who did poorly in school did so because of their low IQs. Further, IQ was in large measure hereditary, and not very malleable. The gap between blacks and whites in educational achievement, like the gap in average IQs, was said to be largely due to genetic causes. That view was repeated by J. Philippe Rushton and Arthur Jensen (2005), who argued that the underrepresentation of blacks in “socially valued outcomes” was genetically determined, and that policies such as affirmative action should be reconsidered in this light.

To claim that IQ scores are largely hereditary is to denigrate the importance of educational and other environmental influences. Taken to an extreme, Rushton and Jensen have straight-facedly reported that the average IQ of sub-Saharan Africans is 70—meaning that about half of the people in this part of Africa are mentally retarded. The desperate environmental conditions and inferior education to which most Africans have been exposed are ignored as causes of any differential in performance.

The political usage of purported low scores for Africans is clearly illustrated by Richard Lynn and Tatu Vanhanen, who wrote:

Hitherto theories of economic development have been based on the presumption that the present gaps between rich and poor countries are only temporary and that they are due to various environmental conditions… . Because of the evidence we have assembled for a causal relationship between national IQ’s and economic disparities, it has to be accepted that there will inevitably be a continuation of economic inequalities between nations. Intelligence differences between nations will be impossible to eradicate because they have a genetic basis (2002, p. 195).

Lynn and Vanhanen choose to interpret the correlation between IQ scores and ethnic and racial differences as a genetic effect, ignoring the obvious environmental and cultural differences between ethnic and racial groups.

SEE ALSO Jensen, Arthur.

BIBLIOGRAPHY

Brigham, Carl C. 1923. A Study of American Intelligence. Princeton, NJ: Princeton University Press.

Jensen, Arthur R. 1969. “How Much Can We Boost IQ and Scholastic Achievement?” Harvard Educational Review 39: 1–123.

Lynn, Richard, and Tatu Vanhanen. 2002. IQ and the Wealth of Nations. Westport, CT: Praeger.

Rushton, J. Philippe, and Arthur R. Jensen. 2005. “Thirty Years of Research on Race Differences in Cognitive Ability.” Psychology, Public Policy, and Law 11 (2): 235–294.

Terman, Lewis M. 1916. The Measurement of Intelligence. Boston: Houghton-Mifflin.

Leon J. Kamin