Intelligence and race

SIGNIFICANCE: Observed differences in mean IQ levels for racial and ethnic groups have generated prolonged and intense controversy on whether intelligence is determined by environment or genetics. The fact that human DNA is nearly identical across racial and ethnic groups argues against race-based genetic differences. The consequences of the position taken on this issue are enormous for social policy, education, and overall race relations.

Contemporary debate on the relationship between intelligence and race can be traced to the nineteenth-century eugenics movement initiated by Francis Galton, Charles Darwin’s half-cousin. Eugenics is a science that aims to improve the hereditary characteristics of a race or breed, usually through selective mating. Galton proposed eugenics as a means of promoting the chances of “superior” races to prevail over the rapid growth of “inferior” races. In Hereditary Genius (1869), Galton concluded that mental traits were as inheritable as physical features. Galton’s colleague, Karl Pearson, the founder of statistical correlation, shared his anxiety about a dysgenic trend, one that favored the “weaker races,” which were reproducing at a higher rate than the “mentally better stock.”

Galton’s efforts to measure intelligence using the speed and accuracy of mental processes as criteria led to attempts to create mental tests. The term “mental test” itself was coined in 1890 by British scientist James McKeen Cattell.

Test Development

During this time, French psychologist Alfred Binet was conducting experiments on his two daughters to develop an accurate method of measuring intelligence. Binet’s major concern was not eugenics but helping schoolteachers distinguish the “malicious” (students who lacked motivation) from the “stupid” (students who lacked the intellectual capacity to succeed). In 1904, Binet created a scale known as the Binet-Simon Scale and advocated that all students be tested with it to separate the “malicious” from the “stupid.”

At the start of the twentieth century, several US psychologists, including Edward L. Thorndike, Naomi Norsworthy, Henry Goddard, and Lewis Terman, all believers in eugenics, were also developing methods to test intelligence. The first version of the Stanford-Binet Intelligence Test, which improved on the Binet-Simon Scale, was produced by Terman at Stanford University in 1916. The notion of intelligence quotient, or IQ—mental age divided by the chronological age of the person tested and multiplied by 100—was introduced by Wilhelm Stern, making it possible to compare people’s performances. Finding that the average IQ of children from upper-class families was 107 and that of working-class children was only 93, Terman concluded that the difference was genetic, not an outcome of the home environment. He questioned the utility of education to help lower-class children become “intelligent voters or capable citizens.”

During World War I, Terman convinced the United States Army to use psychological testing to assess the mental fitness of soldiers. Because many of the 1.7 million men who were tested were not proficient in English or hailed from impoverished backgrounds, their test scores were depressed, leading the researchers to conclude that immigrants from the non-English-speaking world and lower-class Americans were genetically inferior. This influenced immigration policy, helping spread the view that immigrants who were not White Anglo-Saxon Protestants were harming American culture.

In 1939, David Wechsler developed a new IQ test, the Wechsler-Bellevue test. It was very similar to the Stanford-Binet; however, it measured not only verbal skills but also performance skills. In 1955, it was renamed the Wechsler Adult Intelligence Scale (WAIS). Modifications were added later to create the Wechsler Intelligence Scale for Children (WISC) and the Wechsler Preschool and Primary Scale Intelligence (WPPSI). By the end of the twentieth century, hundreds of other tests, including tests designed to measure scholastic aptitude and achievement, had been created and used, highlighting the United States’ fascination with intelligence.

Challenges to IQ Testing

Objections to intelligence testing were first raised as early as 1913 by J. E. Wallace Wallin, a clinical psychologist from Iowa who noticed that children judged to be morons (a term coined by Goddard to refer to someone with an IQ below a certain level) were sometimes unfairly institutionalized. Robert M. Yerks, a psychologist from Harvard University, also warned about the dangers of untrained examiners clinically diagnosing people. In response, the American Psychological Association, at its 1915 meeting, passed a resolution discouraging unqualified individuals from administering psychological testing.

Widespread criticism of psychological testing arose in the 1960s in response to two conclusions that most psychologists had reached: Black individuals as a group consistently scored fifteen points lower than White individuals on standardized IQ tests, and Black individuals did better or at least as well as White individuals on test items involving simple tasks and rote memorization. These conclusions reinforced prevalent negative stereotypes of African Americans, justifying continued discrimination against Black individuals in education and jobs. As criticism of intelligence testing increased, the validity of the tests was challenged in court. Civil rights activists protested against placing children in special education programs based on IQ tests. Charges of racism and examiner bias were made in professional circles as well as in the media. An avalanche of books, articles, and dissertations were produced, mostly challenging the Black inferiority thesis.

Racial/Ethnic Differences and IQ

A definite difference exists between Black and White Americans in mean scores on IQ tests. Most people also acknowledge that regardless of race, class differences exist in mean IQ scores: Upper-class White individuals perform better than lower-class White individuals. What is contentious is the interpretation of these observed differences; that is, whether they stem from the genetic makeups of different groups or are determined by environmental factors.

The controversy was sharpened by an article published by Arthur Jensen, an educational psychologist, in the Harvard Educational Review in 1969. This article held that inherited factors largely accounted for individual differences in human intelligence. Jensen asserted that educational programs designed to raise the IQs of African American children were largely ineffective because of African Americans' genetic limitations. Although he did not deny the influence of environmental factors, he claimed that they were merely “threshold variables.”

Two other prominent psychologists who defended hereditarian thesis for decades are Hans Eysenck, a British psychologist, and Richard Herrnstein, a psychologist from Harvard University. Eysenck supported Jensen’s position and distinguished between two main types of intellectual abilities: abstract reasoning ability, on which IQ is based, and associative learning ability, which involves memory and rote learning. In his estimation, significant racial and social class differences exist in abstract reasoning, although virtually no such differences are found in associative learning.

Herrnstein long maintained that genetics is a significant factor in IQ differences between racial and ethnic groups. His definitive statement, coauthored by Charles Murray, is The Bell Curve: Intelligence and Class Structure in American Life (1994). Herrnstein and Murray insist that race and IQ are genetically linked. Problems of individuals living in poverty—unemployment, crime, low income, and the like—are to be blamed, at least in part, on low IQ. Herrnstein and Murray were pessimistic in assessing programs designed to raise people’s intellectual abilities. Evoking Galton’s fears of a dysgenic trend, the authors believed that the United States is irrevocably turning into a caste society stratified by IQ differences.

Critics of The Bell Curve question the findings of this book on several grounds: Data collected in this book are unreliable; available data do not support the thesis that intelligence is unequally distributed among various races; its authors reach conclusions that are far beyond what the data warrant; and, finally, even if genetics is a factor in intelligence, by the authors’ own admission, it accounts for no more than 5 percent to 10 percent of the variance, far from what is needed to justify their fatalistic view on social stratification.

What Is Intelligence?

The difficulties in resolving the IQ controversy are many: There is no reliable method of isolating the influence of environmental variables from genetics in measuring intelligence, and the concepts used—intelligence, race, and ethnicity in particular—are not precisely definable.

A challenging but critical problem is determining what constitutes intelligence. Intelligence is an abstract construct, rather than an objective entity, constructed to account for specific cognitive abilities. The cognitive skills a scientist identifies to define intelligence when designing a test have significant consequences for test outcomes. Intelligence tests are designed to identify and measure cognitive abilities using quantitative methods based on a theoretical conception of intelligence. Existing intelligence tests measure such abilities as the ability to master common information (such as how many days there are in a year), verbal comprehension (such as what “serendipity” means), knowledge of culturally/legally acceptable ways to deal with problems (such as what one would do if one were the first person in a movie theater to notice smoke and fire), basic mathematical ability (such as the abilities to add, subtract, and multiply), as well as the ability to reason abstractly, compare and contrast different objects or ideas, recall information, manipulate situations mentally, analyze and solve practical problems, distinguish what is essential from what is merely accidental, and learn a new task.

Considerable discussion exists on whether human intelligence is a unitary idea or whether there are several kinds of intelligence. In 1904, British psychologist Charles Spearman proposed that intelligence is made up of two parts: general intelligence (g) and the specific ability measured by particular test items (s). In 1941, R. B. Cattell distinguished between fluid (Gf) and crystallized (Gc) intelligences. Going beyond Cattell, some have recognized the need to consider intelligence as comprising several types, some of which are not measured by available IQ tests. Psychologist Howard Gardner has identified many types and forms of intelligence other than cognitive. Studies also show that intelligence is not fixed but remains changeable over time, depending on new opportunities and experiences. For example, one study found that the IQs of African American college students rise significantly higher as a result of their receiving a college education.

Cultural and Other Biases

Modern research has found that IQ tests measure, more than anything else, knowledge of White middle-class culture. Researchers have noted that subcultural differences play a decisive role in how people grasp and process information and their learning styles and attitudes toward test-taking. Not all groups are equally familiar with the content of the test items presented to them; words are not univocal across subcultures. Individuals taking the test who are of the same ethnicity, race, and gender as the individual who created the test questions are more likely to get a better score regardless of their true ability level.

Researcher Janet E. Helms has suggested that socioeconomic status, culture, and race may influence a person’s performance on the Wechsler Adult Intelligence Scale-Revised (WAIS-R). For example, persons from lower socioeconomic classes may not establish a trusting relationship with the examiner, and individual characteristics of the examiner and their biases in interpreting ambiguous answers may affect test scores. African Americans score lower when tested by White individuals than when tested by Black individuals, a fact known as early as 1936 but ignored until the 1960s. Also, people with limited vocabulary may not understand the instructions given and the explanations offered in response to their questions. Individuals who speak English as a second language are also disadvantaged by typical IQ tests.

Impact on Social Policy

Intelligence testing has become an incendiary issue because of its involvement in continued systemic discrimination of minority groups, including a belief in the superiority of the Anglo-Saxon race, eugenics movements, the enslavement of Black individuals, discriminatory immigration policies, discriminatory hiring policies, and efforts to remedy past injustices. Some observers have pointed out that the intense interest in IQ today parallels its ideological beginnings toward the end of the nineteenth century.

In the nineteenth century, when industrialization was in full swing, the pressures of the marketplace demanded greater social equality and inclusion of all social strata in the social processes. Eugenics and Social Darwinism arose as reactionary movements to oppose programs and policies designed to provide increased opportunities to individuals in low-income and working classes.

The second half of the twentieth century saw a social revolution that, in many ways, paralleled the Industrial Revolution. In the United States, disadvantaged people demanded fundamental changes in social institutions and the abolition of racist policies. Following the civil rights victories of the 1960s, social and educational affirmative action programs were implemented to remedy the effects of past discrimination. The 1980s and 1990s witnessed the rise of a reactionary movement that gradually dismantled many of these programs, and debate about them has continued into the twenty-first century.

While modern psychometrics experts widely assert that flaws in the construction of tests lead to particular racial groups scoring lower on intelligence tests rather than a person's race determining their intelligence, the lasting impact of racist policies using intelligence and other standardized testing remains evident. Race is a socially constructed concept, and applying such a concept to scientific principles of testing does not produce useful results, but an inaccurate basis for perpetuating bias. Modern society has laws limiting intelligence testing use in specific hiring and admission settings.

Bibliography

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Daley, Christine E., and Anthony J. Onwuegbuzie. “Race and Intelligence: It’s Not a Black and White Issue.” The Cambridge Handbook of Intelligence, edited by Robert J. Sternberg, Cambridge UP, 2020, pp. 373–94.

Flyn, James. Race, IQ, and Jensen. Routledge, 1980.

Helms, Janet E. “The Triple Quandary of Race, Culture, and Social Class in Standardized Cognitive Ability Testing.” Contemporary Intellectual Assessment: Theories, Tests, and Issues, edited by Dawn P. Flanagan, et al., Guilford, 1997.

Herrnstein, Richard, and Charles Murray. The Bell Curve: Intelligence and Class Structure in American Life. Free, 1994.

Jacoby, Russell, and Naomi Galuberman, editors. The Bell Curve Debate: History, Documents, Opinions. Random, 1997.

Jensen, Arthur R. “How Much Can We Boost IQ and Scholastic Achievement?” Environment, Heredity, and Intelligence. Harvard Educational Review, 1969.

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Rose, Steven. “Darwin 200: Should Scientists Study Race and IQ? NO: Science and Society Do Not Benefit.” Nature, vol. 457, no. 7231, 2009, pp. 786–88, doi.org/10.1038/457786a. Accessed 10 Dec. 2024.