A Nation of Morons

Stephen Jay Gould

Robert Yerkes was keen to make psychology a science. His opportunity came with America’s entry into the First World War. America was faced with the prospect of working out the capabilities of the thousands of recruits. Yerkes devised an intelligence test that consisted of three parts.

1.     The alpha test was to be taken by literate recruits.

2.     The beta test was to be taken by illiterate recruits, or those who had failed the alpha test.

3.     The individual interview was to be taken by those who had failed the beta test.

The tests often relied upon the recruit’s knowledge of American society.

Procedures were not followed. The black recruits particularly were disadvantaged by the biased testing procedures. Many recruits who had failed the alpha test were not given the opportunity to take the beta test. Results for those who had had the opportunity to be retested with the beta test, after failing the alpha test, demonstrated that retesting usually yielded a higher score.

Depending on the results the men were graded on a scale ranging from A to E (with pluses and minuses). Depending on this grade the recruits were allocated military work that required an intellectual skill commensurate with the grade they achieved in Yerkes tests. Recruits graded C - were to be considered as "low average intelligence-ordinary private". Men graded D were considered "rarely suited for tasks requiring special skill, forethought, resourcefulness or sustained alertness". Men graded D or E were not expected "to read and understand written directions".

Each test took less than an hour to complete. Both tests were similar to many modern intelligence tests; as modern tests are based on Yerkes test.

The alpha test consisted of written questions such as: "Crisco is a: patent medicine, disinfectant, toothpaste, food product?" The beta test was a pictorial test.

A problem with these tests is that they are culturally biased. A problem with the alpha test is that it really measures how widely read a candidate is, rather than intellectual ability. The recruits varied greatly in access to education.

Yerkes asserted that his tests measured "native intellectual ability". Can you solve "Washington is to Adams as first is to..."?

Many recent immigrants did poorly; which was not surprising considering many questions concerned facets of American society at that time. Many immigrants would not have known what Crisco was, for example. Even the pictorial beta test involved the recognition of objects that would have been unfamiliar to people new to America (e.g. a bowling alley).

Yerkes underestimated the number of recruits who would have had to take the beta test. Long queues were forming for the beta test. To alleviate the situation, many illiterate recruits were given the alpha test and naturally failed. Many of these were not given the appropriate beta test. In some camps it became established practice not to retest black recruits.

Boring, then Yerkes assistant analysed the data for 4893 recruits who had taken both tests. He found that the average mental age on the alpha test was 10.775, whereas it was 12.158 for the beta test. This suggests that if the recruits, who had failed the alpha test, had been allowed to take the beta test, they would have ended up with a higher score.

Many of the black and foreign recruits were anxious and befuddled at the new experience of having to take an exam. Many did not know how to hold a pencil. Many did not know as to what use the results of the exam would be put to. The beta test required the use of a pencil, knowledge of numbers and the ability to write them.

Many recruits did not finish the exam in the time allocated. They weren't informed, quite often, about the length of the exam.

After the First World War, Boring studied 160,000 cases, and converted the scores from the three tests into a unitary score for each individual.

Three main facts arose from this analysis.

The average mental age of white American adults was 13 years. A few years before, the average mental age was considered to be 16. At that time there were many eugenicists (people who believed that only genetically strong couples should breed) who blamed the lowering of the mental age on interbreeding between northern European whites and "inferior races". Blacks, southern and eastern Europeans were considered inferior.

The darker skinned southern Europeans and the Slavs of Eastern Europe were found to the less intelligent than western and northern Europeans. The average Russian had a mental age of 11.34, the Italian, 11.01, the Pole, 10.74.

The average mental age of the Negro was 10.41. At one camp it was believed the darker the skin, the less intelligent the Negro was!

Carl Brigham, then assistant professor of psychology at Princeton University published this information, in 1923. The book was called A study of American intelligence.

The data was fiercely defended. For example, Jews were thought to be unintelligent. This contradicted the fact that there were many brilliant Jewish people in the society at that time; Einstein being one of them! Brigham explained this as owing to the greater variability of intelligence within the Jewish population. The intelligent Jews were the exception to the rule!

Later Yerkes realised that the apparent supremacy of the northern Europeans was probably owing to the fact that many had been long established in American society. Southern Europeans and Slavs were relatively recent immigrants. He had thought his beta test would not be biased by length of residence in America.

This view was supported by the finding that there was a significant positive correlation between length of residence in America and the test score. However, the eugenicists argued that the most intelligent people immigrated to America first and the dregs of society made up most of the recent immigrant population.

This data helped the passage of the immigration restriction act of 1924. Quotas were set on the number of immigrants allowed into America. The level was set at two percent of people from each nation recorded in the 1890 census. The 1890 census was used, as there were very few southern Europeans, Slavs and Jews, etc. in America at that time.

Many would be Jewish refugees, trying to flee from Nazi Germany in the 1930's, were not allowed into America because of these quotas.

Points to note

• Many psychologists in America during the First World War believed that intelligence was innate. They therefore were unlikely to attribute poor test results to social deprivation, being unfamiliar with the culture, or the effects of slavery and subsequent prejudice.
• This illustrates the effects of dogma. Psychologists and other scientists can sometimes be blinded by their own theories. They may be so intent on proving their theories to be correct that testing can become biased towards supporting their theories and the interpretation of results may also be biased.
• A biased interpretation might confuse cause and effect. For example, Yerkes argued that less intelligent men spent less time in school because they were unintelligent. The real explanation was most likely that deprived men who had little education did poorly on Yerkes intelligence test.
• One should not infer a cause from a correlation. This is because:
• you have no way of telling which variable effects the other variable (as illustrated in the previous point)
• Some third variable may be acting upon the two correlated variables. For example, racial segregation could explain a lack of schooling amongst African Americans and poor test results.
• If one is to infer which variable affects which, there must be a theory that explains the relationship between the two variables. Yerkes attempts to support his theory by invoking the same theory to explain the relationship between the two variables; he thus has what is known as a circular argument.