Intelligence tests emerged in the Progressive Era as a means for evaluating individual abilities, channeling individuals into particular lines of education and work, and restricting immigration. Battles over the nature of intelligence, however, had been waged for centuries. In the middle of the 19th century, two prominent scientists formally structured the terms of the debate. John Stuart Mill and Francis Gal-ton promoted two diametrically opposed theses regarding the development of behavior and intelligence. Where Gal-ton saw nature, Mill saw nurture. Galton was convinced that genetics were the predominant force in the development of intelligence. Mill, on the other hand, championed the idea that social conditioning was the prevailing force. Galton used his idea of the supremacy of nature to develop the first intelligence tests, which were hindered by his preconceptions. He saw a direct correlation between intelligence and motor functions. Thus, his tests assessed motor skills and not intelligence.
Dozens of scientists followed in Galton’s footsteps. It was not until Alfred Binet (1857-1911) developed his theories, based on assumptions closer to Mill than to Galton, that real progress was made at charting human intelligence. Binet pioneered the method of analysis that is still prevalent in many intelligence tests today. When Binet’s theories were fully developed, the resulting tests were far superior to anything that Galton or his followers had offered. Tests that followed Binet’s fundamental assumptions attempted, and to a degree succeeded, in ascertaining some of the roots of intelligence.
As variations of the Binet intelligence tests became the norm in the early 20th century, they were used to distinguish differences. The first major distinction made was based on sex. Men and women scored differently on the test. As a result, assumptions were made regarding the relative intelligence of men and women. The tests also were used in an attempt to determine who was more likely to commit a crime, and it was discovered that prisons were filled with men and women who tested low on the Binet
Scale. The term “feebleminded” was used to describe adults who tested at a level below that of a 13-year-old child. Both of these theories were challenged soon after they were presented. Despite advancements in testing methods, the test was culturally biased in its measurements.
During World War I the U. S. Army used the best available test, the Stanford-Binet intelligence test, to determine the mental competency of soldiers. The tests, like those before them, relied on assumptions that those tested would have a firm understanding of American history as well as social and cultural norms. As a result, testees without the requisite background were deemed less intelligent. The army dropped the tests in 1919, but alternative intelligence tests were soon developed and implemented to measure intelligence both in and out of the Armed Forces.
During the 1920s, intelligence testing became closely associated with ethnic, racial, and class-based stereotypes. During that decade of ethnic and racial division, intelligence tests were used to support limits on the rights and liberties of ethnic and racial minorities. They provided support for legal restrictions on immigration. While ethnic and racial minorities were the primary targets, these were not the only stereotypes to be reinforced through intelligence testing. It became an effective tool in reinforcing the political, social, and economic systems. Simply put, intelligence tests provided the rationale for social inequality. But when wealthy rural Americans scored poorly on the tests, the idea that the rich were naturally smarter than the poor was undermined.
Intelligence tests presented more new questions than they answered. The nature of intelligence, whether determined by nature or nurture, was not solved by the tests. In fact, IQ tests provided ammunition for proponents of both schools. Those who supported the idea that intelligence was rooted in heredity could use the scores as proof. Those who championed nurture over nature also employed them as evidence of the importance of environment in cultivating intelligence.
See also immigration; race and racial conelict.
Further reading: Carl Degler, In Search of Human Nature: The Decline and Revival of Darwinism in American Social Thought (New York: Oxford University Press, 1991); Raymond Fancher, The Intelligence Men: Makers of the IQ Controversy (New York: Norton, 1985).
—Steve Freund
World History
