It Began with Galton

The concept that intelligence could be or should be tested began with a nineteenth-century British scientist, Sir Francis Galton. Galton was known as a dabbler in many different fields, including biology and early forms of psychology. After the shake-up from the 1859 publishing of Charles Darwin's "The Origin of Species" (read the e-book now!), Galton spent the majority of his time trying to discover the relationship between heredity and human ability.

The general attitude of the time held that the human race had a tiny number of geniuses and a tiny number of idiots, while the vast majority was composed of equally intelligent people. Whatever someone achieved in life was the result of hard work and willpower. Although a comfortable view, this wasn't enough to satisfy Galton, who believed mental traits are based on physical factors, and are in fact inheritable traits--the same as eye color or blood type.

Galton's ideas on intelligence were influenced also by the work of a Belgian statistician named Lambert Adolphe Jacques Quetelet. Quetelet was the first to apply statistical methods to the study of human characteristics, and actually discovered the concept of normal distribution--the tendency for the bulk population to fall somewhere between two extremes, with numbers dropping sharply at either extreme. If plotted on a chart, these values assume a shape roughly like that of a bell.

Galton's Ideas in America

Galton published his ideas on hereditary intelligence in a book titled Hereditary Genius, which is recognized as the first scientific investigation into the concept of intelligence. In the 1890s, an American student of Galton's, James McKeen Cattell, brought the idea of intelligence testing to America. Cattell's work caused brief but intense mental testing in America. What proved to be the test's downfall, however, was that scoring well on the Galton test did not indicate if a student would do well on schoolwork, which was considered the practical proof of good mental ability.

Binet and child intelligence

Meanwhile in France, a psychologist named Alfred Binet was busy devising tests to rate child intelligence. Like Galton, Binet was passionate about testing and measuring human capabilities. His understanding of intelligence evolved through intense trial-and-error testing with local students. Working with groups of average students and groups of mentally handicapped students, Binet discovered certain tasks that average students could handle but handicapped students could not. Binet calculated the normal abilities for students at each age, and could pinpoint how many years a student's mental age was above or below the norm.

The Paris educational authorities came across Binet's work and asked him to devise a test that could be used to separate normal children from special needs students. These tests were held between an interviewer and a single student, with questions like: "What is the difference between wood and glass?" and "Make a sentence using the words, Paris, fortune, gutter."

The idea that a test could determine a child's "mental age" became enormously popular. Just before World War I, a German psychologist named Wilhelm Stern suggested a better way of expressing results than by mental age--Stern determined his results by finding the ratio between the subject's chronological age and their mental age. Therefore, a 10-year-old scoring one year ahead of their chronological age (110) would be not as significant as a 5-year-old scoring one year ahead (120).

Terman coins intelligence quotient

An American psychologist named Lewis Terman coined the term intelligence quotient for Stern's Binet test scoring system. An average IQ score on a Binet test was 100. Any score above 100 was deemed above average, while any score below 100 was below average.

Pioneers have reservations

Recognizing that the Binet test had its limitations, both Binet and Stern doubted IQ scoring actually represented a fixed inborn quantity of intelligence. As Stern wrote in 1914: "No series of tests, however skillfully selected it may be, does reach the innate intellectual endowment, stripped of all complications, but rather this endowment in conjunction with all influences to which the examinee has been subjected up to the moment of testing."

Despite reservations of these two pioneers, the Binet test was enthusiastically accepted in America. In 1916, a Binet test was administered to a prisoner on trial for murder. Because the prisoner fared so poorly on the test, the Wyoming jury acquitted him by reason of his mental condition.

U.S. Army embraces IQ testing

The greatest spurt in American IQ testing came in 1917, when America entered World War I. Binet's original tests were designed to be administered to children on an individual basis, but the U.S. Army was faced with the dilemma of sorting huge numbers of draftees into various Army positions. To solve this problem, the Army put together a committee of seven leading psychologists to devise a mass intelligence test. The chairman of this committee was Robert Yerkes, who later admitted he was chosen simply because he was president of the American Psychological Association that year.

Luckily, one of the seven selected psychologists, Lewis Terman (coiner of the term intelligence quotient), had a pupil named Arthur Otis, who had already begun constructed a group intelligence test when the Army decided it needed one. By and large, the committee adopted the material Otis had already prepared, and in six weeks the tests were ready for the printers. A few weeks after that there was a trial run with four thousand men. Less than two years later, by the beginning of 1919, nearly two million American men had taken the Army intelligence tests.

The Army scores were not expressed using the intelligence quotient, but instead by simply awarding points for correct answers. On the basis of these points, men were divided into one of five classes, ranked from A to E.

IQ after WWI

Soon afterwards, many companies began testing programs to determine who would be hired, promoted or transferred. But the greatest market for intelligence tests was the schools. In the years following World War I, practically every school system in the country began some sort of intelligence scoring program. Of course, intelligence testing had its fair share of detractors, including Walter Lippmann, a well-known columnist and social commentator of the time. In 1922, he wrote: "One only has to read around in the literature of the subject...to see how easily the intelligence test can be turned into an engine of cruelty, how...it could turn into a method of stamping a permanent sense of inferiority upon the soul of a child...."

IQ falls out of favor (race discrimination)

In the 1960s and '70s, IQ tests began to fall out of favor, partially because of racially and culturally specific test questions. In 1964, the New York City Board of Education did away with IQ testing entirely, and other boards of education followed suit, often reluctantly. Many lawsuits related to job hirings and denied education also took place during this time, usually finding the IQ testers guilty of discrimination.

Gardner's theory of multiple intelligences

The concept of intelligence has continued to evolve, despite problems with and misuses of IQ testing. In 1983, Howard Gardner argued that "reason, intelligence, logic and knowledge are not synonymous...", setting forth a theory of multiple intelligences. Gardner defined seven distinct intelligences: logical-mathematical, linguistic, spatial, musical, bodily kinesthetic, interpersonal and intrapersonal intelligences. The concept of multiple intelligences helped broaden the idea of "intelligence" from a mathematical and verbal understanding, which had become cemented into American culture through years of national testing (i.e. the SATs).

U.S. reliance on IQ testing

Gardner's ideas have made their way into education, and are currently being used by many school districts. But traditional intelligence and scholastic aptitude testing has continued to gain acceptance and force in U.S. education. Today, certain colleges refuse to accept students below certain prestigious scores on the SATs and many private and premier public schools accept students almost solely on the basis of test scores.

While many of pioneers of intelligence testing have called for the removal of intelligence testing from schools, the American education system embraces IQ testing as a quick way to rate student ability. As intelligence psychologist Arthur Jensen wrote, "Achievement itself is the school's main concern. I see no need to measure anything other than achievement itself."

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Bibiliography

Cohen, Daniel. Intelligence, What Is It?. New York: M. Evans and Company, 1974.

Fancher, Raymond E. The Intelligent Men: Makers of the IQ Controversy. New York: W. W. Norton & Company, Inc., 1985.

Gardner, Howard. Frames of Mind. New York: Basic Book Inc., 1983.

Gardner, Howard. Intelligence Reframed. New York: Basic Book Inc., 1999.

Jensen, Arthur. Bias in Mental Testing. New York: The Free Press, 1980.