The aim of this review article was to expose
the fundamental problems involved in Yerkes attempts to measure intelligence
during the First World War.
Yerkes was a psychologist and in 1915 mental testing did not enjoy much
credibility, so Yerkes tried to change this. Yerkes was concerned to
establish psychology as a ‘hard’ science and believed that using such
a ‘scientific’ approach to mental testing looked a promising route to
achieve this. He believed that intelligence testing should be as rigorous
as any other science and he equated science with number and quantification
During the First World War (1914-18)
Yerkes found an opportunity to promote the use and status of mental testing
and therefore the status of psychology as a serious science. The American
military gave Yerkes permission to carry out mental tests to over 1.75
million army recruits.
In 1917, Yerkes devised three types of
Army Alpha - A written test for literate
recruits. The Alpha test had eight parts, such as analogies, filling in the
missing number, and unscrambling a sentence. These types of tests have now
become common in modern IQ tests.
Army Beta - A pictorial test for men who
were illiterate or who failed the alpha. The Beta test had seven parts
including running a maze, number work and the picture completion task.
Individual Examination - An individual
spoken test for men who failed the Beta
The Alpha and Beta tests could be
administered to large groups and took less than an hour to complete.
Yerkes argued that his tests measured
‘native intellectual ability’, in other words, innate intelligence which was
unaffected by culture and educational opportunities.
Yerkes identified three ‘facts’
which were discovered from the intelligence testing.
The average mental age of White American adults was 13. The score
of 13 was at the top of the category of ‘moronity’. That is why the
title of the article is ‘A Nation of Morons’, because the ‘data’
showed that the USA was just that. Terman had previously set the
standard at 16.
It was possible to grade European immigrants by their country of
origin. The average man of many countries was a moron, with the fair
people of Northern and Western Europe scoring higher than the Slavs of
Eastern Europe and the darker people of Southern Europe. (The average
Russian had a mental age of 11.34; the Italian, 11.01; the Pole, 10.74).
The average score of Black men was
10.4, which was considerably below the White average.
findings were used to support the idea of genetic differences between
‘races’. Carl Brigham, one of Yerkes’ colleagues, using a genetic
explanation of the data proposed the racial superiority of the Nordic people
(from Northern Europe).
Similarly it was argued that the average
scores from the different national groups reflected innate racial
Based on these ‘facts’, and lobbying from
scientists who supported the eugenics argument, the Immigration Restriction
Act (1924) was passed by the US Congress. The Act set immigration quotas
based on the US population in 1890 (over 30 years prior to the Act). This
year was used as the benchmark because immigration from Southern and Eastern
Europe had been relatively low before this date.
During the next 20 years, conditions
deteriorated dramatically in Europe for Slavs and Jews as the Nazi
governments enacted policies of ‘racial purity’ culminating in genocide.
Estimates suggest that the immigration quotas barred up to six million
people from Europe, a number with great significance in the history of
Gould identified many problems with the
mass intelligence testing. In particular he pointed to the cultural bias in
The Beta test required a high level of
cultural and educational knowledge to be completed successfully. For
example, recent immigrants would have to be familiar with phonograms, tennis
courts and light bulbs.
There were also a number of problems in
the administration of the tests. In particular, many who were illiterate in
English were still allocated to the Alpha test and so scored zero or near to
zero. Because Yerkes had overestimated the level of literacy the queues for
the Beta test became very long, leading to the inappropriate re-allocation
of men to the Alpha test. Failures on the Alpha tests were often not
recalled to take the Beta test. Therefore, recent immigrants who had a poor
grasp of English, and Black men who had not been given much, if any, formal
education, were unable to score on the Alpha test.
Another problem was that even the Beta
test required the use of pencil and the writing of numbers, and many men had
never even seen or used a pencil before.
Conditions in which the tests were taken
were also unsatisfactory. For example, the time allowed was insufficient
and an air of panic surrounded the whole procedure. To men unused to the
written word or number, the event must have been extremely bewildering.
Gould argues that with such problems, the
data should be looked at with considerably scepticism.
Gould clearly exposes in his review some
of the ridiculous and racist explanations put forward by Yerkes and his
Gould’s article highlights the scientific
racism, (i.e. the use of bogus scientific arguments to oppress another
group) in the arguments made by Yerkes and uncovered some of the awful
consequences of this racism.