An IQ-test is unsuitable to measure pure intelligence independent of culture and history.

How IQ-scores encourage racism

Intelligence is one of the most studied aspects of human cognition. However, it seems that IQ – the intelligence quotient – does not accurately represent intelligence. In fact, the way IQ is determined encourages racism, and the scientific community is not free from these biases.

This post is also available in Dutch.

The intelligence quotient (IQ) was created to easily quantify one’s intelligence. Although there is no scientific consensus on what intelligence actually is, quite soon scientists differentiated between two types of intelligence: fluid intelligence and crystallised intelligence. Fluid intelligence is the capacity to solve new problems, and crystallised intelligence pertains to knowledge-based skills. Crystallised intelligence increases with age and never decreases, whereas fluid intelligence is more stable and only decreases as you get older.

How do you measure intelligence?

The first problem arises when you want to calculate an IQ-score. How do you even measure someone’s intelligence? Many famous IQ-tests (such as the WAIS: Wechsler Adult Intelligence Scale) contain challenges that many people from western countries can easily solve, but are much harder for people from non-western countries. Think of, for example, challenges about organising objects that are used differently (or not at all) in non-western countries, or about ‘common’ knowledge that is irrelevant in certain areas of the world. And who even decides what is and isn’t a sign of intelligence?

Measuring IQ depends on culture

For this reason, so-called ‘culture-friendly’ IQ tests have been developed that take cultural differences into account. One such example is to organise universally used, abstract figures, such as squares and triangles, rather than objects that may come from a particular culture. But even this solution can cause new problems. There are cultures where there is no word for ‘square’, because the shape is in no way relevant for their society. These linguistic differences determine how people perceive relations between objects and therefore influence one’s performance on such an IQ test. It would make much more sense to ask certain tribes about their knowledge of nature, how to train animals or how to survive in the wilderness; skills and knowledge that most people in the western world do not have. Even though intelligence can be a universal human construct, the most effective way to measure this intelligence is not universal, but rather depends on the environment where one was raised.

IQ and racism

The consequence of common IQ tests being biased against people from some cultures is that certain populations are unfairly typecast as unintelligent. The IQ-scores are not interpreted within the context of culture and socio-economic climate, so that differences can induce the racist idea that certain (often non-Western) populations are naturally less intelligent than other (e.g., Western) populations. But those differences in IQ-scores can be explained by the Western nature of the test. An IQ-test is therefore unsuitable to measure pure intelligence independent of a country’s culture and history. Group differences in IQ within countries are often caused by environmental factors such as unequal opportunities and differences in socioeconomic status and education, and do not provide any information on underlying biology.

Racism in scientific research

The problem does not lie only in IQ-scores: the current use of IQ creates scientific research that unfairly fuels racist ideas. For example, a highly regarded journal (Psychological Science) published an article in February 2020 that researched the relationship between IQ, violence, and religion. The researchers used a dataset of national IQ-scores where some countries had an average IQ of 50. Just to be clear, a score of 100 is usually considered average­1 and scores below 70 are said to indicate an intellectual disability. It soon became clear that these unlikely low scores were the consequence of very unrepresentative samples from the low-scoring countries. For example, the average IQ of Somalia (67.7) was based on a group of 8- to 18-year-old Somalian refugees in a refugee camp in Kenya. This dataset should never have been used. What followed was a lot of criticism from other scientists on the racist implication that certain African populations have intellectual disabilities, and the article was withdrawn a month ago.

Racism in the scientific machine

But how could this article have even been published? The person responsible for the publication process of the article has indicated in an extensive statement that he and his team were not aware of the racist implications of the article. He admitted that the team consisted of only white people. This is typical for science, a field that is primarily made up of white people.

Racism is not only about explicit behaviour towards certain populations; our actions are mostly determined by implicit prejudices. Even “neutral” and “objective” science cannot escape this and has issues with racism. If we ever want to end racism, this is something of which we must be aware and should point out to each other.

1The average of 100 is based on the population of the United Kingdom. How representative of the world is that?

Relevant sources

‘Flawed estimates of cognitive ability in Clark et al. Psychological Science, 2020:

An extensive discussion on the problems of IQ on Twitter (substantiated with scientific literature):

#ShutDownStem/#ShutDownAcademia was an initiative to shut down science for one day and to work on a plan of action against racism:

Original language: Dutch

Author: Felix Klaassen
Buddy: Jeroen Uleman
Editor: Floortje Bouwkamp
Translator: Wessel Hieselaar
Editor translation: Rebecca Calcott

Featured image courtesy of Pixabay via Pexels

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