William Stern, the Creator Yet Fiercest Critic of the Concept of IQ

The man who coined the concept of IQ ended up being its biggest detractor. In fact, William Stern warned that classifying an individual's mental aptitude should also take into account everything, from their emotions to their determination.
William Stern, the Creator Yet Fiercest Critic of the Concept of IQ
Valeria Sabater

Written and verified by the psychologist Valeria Sabater.

Last update: 25 July, 2023

Have you ever been given an IQ test? Have you had to complete a psychometric test in a selective process? There are various instruments for these purposes, from the Wechsler Adult Intelligence Scale (WAIS) to the challenging Raven’s Progressive Matrices (RPM) test.

These resources aren’t only intended to show us how efficient we are at a cognitive level. They also classify us on our supposed social abilities. For example, think about the Mensa association. It’s a community into which only people with high abilities and who exceed the 98th percentile can enter. In fact, evaluating IQ is still important in many areas and scenarios.

For instance, they’re frequently used in court proceedings to assess the psychological maturity of defendants. Also when a person has suffered a head injury and medics seek to know the extent of their injuries. Then, of course, there are intelligence tests that are used to detect the best candidates for certain jobs. However, many experts have been warning of one particular aspect of these kinds of tests for decades.

They claim that using IQ as an exclusive way to measure an individual’s aptitude can be discriminatory and also limiting. Interestingly, the first person to warn about the danger of using this indicator as the only mechanism to evaluate human talent and aptitude was its own creator: William Stern.

The American Psychological Association applied intelligence tests during World War I to select recruits. The tests were clearly discriminatory in deducing that certain European immigrants living in the United States were mentally inferior.

Person taking a psychological test to measure William Stern's IQ
William Stern regretted popularizing his concept of intelligence quotient (IQ).

Who was William Stern?

William Stern (1871-1938) was a German psychologist and philosopher famous for his remarkable contributions to the field of intelligence and personality. He was the first to coin the term, intelligence quotient (IQ) and created innovative instruments to detect aptitude and talent in individuals. This immediately opened up an era in which selection processes began to be regulated by these instruments.

One area that benefited from the introduction of IQ was child development. That’s because psychologists had spent decades trying to assess the mental ages of children and appreciate individual differences in development. Figures like Alfred Binet and Théodore Simon had already tried. However, William Stern provided the defining key.

His theory proposed the following formula: IQ= cognitive age/chronological age x 100. Chronological age refers to the individual’s date and year of birth. Cognitive is a standardized measure that measures cognitive abilities compared to the average performance of subjects of the same age.

This data established an individual’s mental retardation at an IQ level of 70-85. Nevertheless, Stern warned that this formula shouldn’t be used as the only method to categorize the intelligence of an individual. His warnings were ignored.

“Mental frailty or borderline retardation cannot be assessed by IQ alone.”

-William Stern-

A strong interest in child development

Stern married another psychologist, Clara Joseephy. They were both interested in child development, which led to the implementation of a famous project. In fact, the Sterns studied their three children from birth to 18 years of age to understand how they established language and the entire set of cognitive processes: memory, attention, judgments, reasoning, etc.

Dr. James T. Lamiell conducted a study in which he collated all the conclusions that the couple reached in their family study. The IQ test didn’t measure certain aspects that also formed as a part of children’s intelligence. In fact, Stern highlighted the importance of volitional variables (motivation, resolution) and emotional ones.

Illuminated child's brain symbolizing the molecule that rejuvenates aging brains
For William Stern, emotions were also decisive in evaluating intelligence.

The IQ pioneer who ended up as its biggest critic

The person behind the IQ concept ended up being its biggest critic. It’s one of the most curious ironies in the history of psychometry and the study of intelligence. However, not everyone knows that William Stern didn’t want his name to be associated with this theory and its classic formula (Lamiell, 2003, p. 1).

In 1933, he wrote the following words:

“Under all conditions, human beings are and will remain the centers of their own psychological life and of their own worth. In other words, they remain persons, even when studied and treated from an external perspective with respect to the goals of others… My feeling is that psychotechnicians degrade people by using them as a means to the ends of others.”

-Stern, 1933, cited in Lamiell, 2003-

The philosophy of personalism against the mercantilism of personnel selection

William Stern developed IQ and other psychometric approaches to get to know people better, not to delimit their potential based on a percentile. As a matter of fact, he was a defender of the philosophical theory of personalism, an approach that perceives the human being as a free and unique individual who has an inherent value just for being who they are.

Individuals should never be treated like merchandise. They should be given the opportunity to actualize their potential whenever they want. This contrasts with the idea of intelligence tests. However, the labor industry and also the military have long selected people based on the IQ indicator.

Stern regretted all his life that psychotechnics turned people into machines for the job market or the military. Many saw their opportunities completely restricted for the simple fact of achieving a low or average score on these tests. This was at the beginning of the 20th century. Little did the reluctant father of the IQ test didn’t know that this trend would last for several more decades.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Allport, Gordon (Oct 1938). “William Stern: 1871-1938”. The American Journal of Psychology. 51 (4): 772–773. JSTOR 1415714
  • Lamiell, James T. (2003), Beyond Individual and Group Differences. Sage Publications, ISBN 9780761921721
  • Lamiell, James T (2009). “Some Philosophical and Historical Considerations Relevant to William Stern’s Contributions to Developmental Psychology”. Zeitschrift für Psychologie. 217 (2): 66–72. doi:10.1027/0044-3409.217.2.66
  • Stern, William (1914) [1912 (Leipzig: J. A. Barth, original German edition)]. Die psychologischen Methoden der Intelligenzprüfung: und deren Anwendung an Schulkindern [The Psychological Methods of Testing Intelligence]. Educational psychology monographs, no. 13. Guy Montrose Whipple (English translation). Baltimore: Warwick & York. ISBN 9781981604999

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.