One hundred years ago, on April 6, 1917, the United States entered World War I by declaring war on Germany. When American psychologists heard the news, they dispatched Robert M. Yerkes, then president of the American Psychological Association, to Canada to confer with Carl C. Brigham of the Canadian Hospitals Commission to learn about the contributions that Canadian psychologists were already making to the war effort. Yerkes was a comparative psychologist at Harvard University, with a joint appointment as consulting psychologist at Boston State Psychiatric Hospital, where he helped develop a scale of intelligence.

He was also a born organizer. On his return to the United States, he set up a dozen committees to explore the useful roles that psychologists might play in the war. While most of these committees led nowhere, Yerkes successfully established the Committee on Methods of Psychological Examination for Recruits, which included Henry Goddard and Lewis Terman, two pioneers of intelligence testing in the United States (who had translated the Binet-Simon scale of intelligence into English). The committee had originally planned to implement a variety of tests for recruits, but they eventually restricted themselves to intelligence testing, with the aim of “segregating and eliminating the mentally incompetent”—or, to use the parlance of the day, the “feebleminded.” Their work initiated the largest program of psychological testing that had been attempted to that date, but also provided powerful impetus for two movements that had been developing since the turn of the century: the call for immigration quotas and the sterilization of the feebleminded.

Intelligence testing in the Army

In May 1917, realizing that it would be impractical to test intelligence individually, Yerkes’ committee spent two weeks developing tests that could be administered in groups and conducting trials of these tests at educational institutions and Army bases. Working through the National Research Council, Yerkes proposed group intelligence testing to the Army, which created the Division of Psychology under the Surgeon General. When Yerkes’ plan for the mass intelligence testing of Army recruits—the Army Testing Project—was approved, he commissioned a team of 400 Army personnel to administer group intelligence tests to all Army recruits. This included the Alpha written test for literate soldiers and the Beta pictorial test for those who could not read English. By the end of the war, close to 2 million soldiers had been tested.

One of the striking findings of the Army Testing Project was that around half of the Army recruits tested at or below the level of “moron.”

On the basis of the test results, about 8,000 men were recommended for immediate discharge on grounds of mental incompetence another 19,000 were assigned to labor and noncombat battalions. Psychologists who participated in the Army Testing Project felt they had made a valuable, practical contribution, and found their work an exhilarating contrast to normal academic life. (Yerkes himself regretted that the war did not last longer.) Publications such as Harper’s Magazine and The New York Times lauded their achievement. However, the Army itself was less than enthusiastic, and discontinued the program shortly after the war ended. (In contrast, the Army judged the other major psychological war committee a great success. Walter Dill Scott’s Committee on the Classification of Personnel in the Army developed scales for officer selection, and in 1918 Scott was awarded the Distinguished Service Medal.) Though it was short-lived as part of military efforts, the Army Testing Project had significant consequences in the social sphere.

Fears of a creeping “feeblemindedness”

One of the striking findings of the Army Testing Project was that around half of the Army recruits tested at or below the level of “moron.” The term moron had been introduced by Henry Goddard to classify adults with the mental age of a child between 10 and 12. Individuals judged to have a mental age between 4 and 10 years were classified as low-grade, medium-grade, or high-grade imbeciles; those with a mental age of 3 or under were classified as idiots. These classifications were based on Goddard’s translations of the 1908 and 1909 Binet-Simon intelligence scale, which Terman revised in 1916. Terman’s revision, which was later known as the Stanford-Binet test (after Terman became professor of psychology at Stanford University), became the standard American intelligence test.

In the first decade of the 20th century, Alfred Binet and Theodore Simon introduced in France a scale for measuring a child’s intelligence. The scale comprises 54 tests. These were arranged according to appropriate age levels between 3 and 13 years old, calibrated so the average 9-year-old would score at level 9. Binet and Simon used the term “mental level” rather than the later term “mental age” because they believed their scale was a useful means of identifying children in need of remedial education (for whom they devised special educational programs) rather than as a fixed measure of intelligence. However, Goddard and Terman treated the Binet-Simon tests as though they measured genetically determined intelligence.

The disconcerting findings of the Army Testing Project led Yerkes to conclude that “feeblemindedness… is of much greater frequency than had previously been supposed” and caused a moral panic among psychologists, politicians, and the public at large. A number of works that were both alarmist and racist publicized the supposedly dire consequences of allowing immigrants from eastern and southern Europe to displace (and contaminate) the original Nordic (northern and western European) stock. For example, Carl Brigham, who had advised Yerkes on the Canadian war effort and later helped to develop the Alpha intelligence test, claimed in his 1923 book A Study of American Intelligence that the average intelligence of recent immigrants was less than that of native-born Americans. The average intelligence of Americans, he argued, had been declining since 1900.

There were those who critiqued these hysterical responses. The behaviorist John B. Watson and the anthropologist Franz Boas were critical of the hereditarian presumptions of the intelligence testers. Journalist Walter Lippmann, in a scathing series of articles in New Republic, condemned intelligence testing as an “engine of cruelty” based upon the pretentious abuse of the scientific method. Their efforts were to little avail. Before the members of Congress, Harry Laughlin, superintendent of the Eugenics Records Office at Cold Stream Harbor, voiced concerns about the pollution of the national stock. This led in 1924 to the National Origins Act, which restricted immigration to quotas that were based on the 1890 census—a census taken before the 20th century wave of eastern and southern European immigration.

State-sanctioned eugenics

Several years earlier, fears about degeneracy in the general population had led Charles Davenport, author of Eugenics: The Science of Human Improvement by Better Breeding, to found in 1910 the Eugenics Records Office at Cold Stream Harbor, Long Island, an office dedicated to research on the inheritance of psychological traits, including intelligence and feeblemindedness. The British hereditarian Francis Galton had previously coined the term eugenics (from the Greek for “well-born”) to describe his suggested program for improving the national “stock.” Galton, like many of his contemporaries, had recognized that one of the implications of his half-cousin Charles Darwin’s theory of evolution was that human progress was not inevitable: humankind, if left to its own devices, was just as likely to degenerate as to progress. This concern was seemingly confirmed by rising crime, alcoholism, tuberculosis, and feeblemindedness among the Victorian lower classes.

“It is better for all the world, if instead of waiting to execute degenerate offspring for crime…society can prevent those who are manifestly unfit from continuing their kind… Three generations of imbeciles are enough.”

Galton originally recommended programs of positive eugenics. In these programs, the “highly-gifted” (assessed via Galton’s own measures of human intelligence) should be encouraged through generous financial government incentives to breed and to breed often. However, the Boer War, in South Africa, shifted Galton’s view. The war lasted from 1899 to 1902, far from the quick and decisive victory that many expected when the British Empire was pitched against a nation of farmers. Galton and his protégé Karl Pearson fretted that reduced levels of “national efficiency” were in fact a threat to national survival. They suggested programs of negative eugenics, through which the state would institutionalize and sterilize those deemed mentally defective.

In 1914, before working on the Army Testing Project, Yerkes and Goddard had served on the Committee to Study and to Report on the Best Practical Means of Cutting Off the Defective Germ-Plasm in the American Population, a research committee that had been commissioned by the American Breeders Association. After considering the options of life segregation (compulsory institutionalization), restrictive marriage laws, eugenic education (to encourage educable defectives to voluntarily decline to propagate their kind), general environmental betterment (to improve social conditions), and euthanasia, they recommended segregation and sterilization as the “most feasible and effective in cutting off from the human population the supply of defectives.”

State legislatures quickly adopted their recommendation. By 1930, around 30 states had sterilization laws on their books, and within five years approximately 35,000 individuals had been sterilized. Harry Laughlin, who had promoted the National Origins Act in Congress, published in 1922 a Model Eugenical Sterilization Law, which became the template for most state laws. The law targeted those persons “who, because of degenerate or defective hereditary qualities, are potential parents of socially inadequate offspring,” and its stated aim was to “prevent certain degenerate human stock from reproducing its kind.”

Once again there was opposition, but again it came to naught. In 1927 the Supreme Court heard the case of Buck v. Bell. At question was the right of the State of Virginia to sterilize Carrie Buck, who along with her mother and illegitimate daughter, Vivian, had been classified as feebleminded. (Vivian’s illegitimacy was taken as evidence of Carrie’s feeblemindedness; in fact, Carrie had been raped by a nephew of the foster parents who committed her.) The Supreme Court ruled in favor of the State of Virginia, and Carrie Buck was sterilized. Justice Oliver Wendell Holmes Jr., writing in favor of the majority, claimed:

“It is better for all the world, if instead of waiting to execute degenerate offspring for crime, or to let them starve for their imbecility, society can prevent those who are manifestly unfit from continuing their kind… Three generations of imbeciles are enough.”

This movement had international appeal. Laughlin’s Model Eugenical Sterilization Law also formed the legal basis of Germany’s 1933 Law for the Prevention of Genetically Diseased Offspring, which sanctioned the sterilization of 350,000 “hereditarily diseased” persons, including anyone deemed mentally deficient, schizophrenic, manic-depressive, or epileptic, as well as anyone who happened to be congenitally blind, deaf, or severely deformed.

Enthusiasm for the sterilization of the feebleminded waned in the United States after Nazi Germany extended eugenic programs to wholesale extermination programs. By the 1930s many psychologists had recanted their earlier positions. Carl Brigham, for one, dismissed his earlier claims about inheritance and degeneracy as “without foundation.” Nonetheless, the practice continued in the United States into the 1960s, by which time around 65,000 individuals had been sterilized. The last sterilization law was only removed in 1981.

The Army Testing Project had one other consequence of social significance. After the war, Carl Brigham joined the psychology faculty at Princeton University, where in 1925 he devised a college admissions test based upon the Army Alpha test, which he had helped to create. The following year, Brigham developed his test into the Scholastic Achievement Test (SAT) for the College Board. Once again, he had a change of heart, later condemning the use of the SAT and opposing the creation of the Educational Testing Service. By then, of course, that train had long since left the station.