Inventing IQ

How IQ Tests Were Born From War

The concerted effort to quantify intelligence took root in the early 20th century, propelled by the rise of industrialization and the recognition of psychology as a science. It reached a crescendo during World War I, resulting in the well-known measurement we refer to today as the IQ test.

Initially, the concept behind the first "intelligence test" was laudable: identifying schoolchildren who required additional support. In 1904, French psychologists Alfred Binet and Theodore Simon were commissioned by their government to devise this evaluation. They created questions concentrating on areas not directly taught in schools, such as attention, memory, and problem-solving skills. This became the Binet-Simon Scale; the first recognized IQ test.

In 1916, Lewis Terman, a psychology professor at Stanford University in the US, developed an English test version. The test was divided into verbal and non-verbal IQ segments for the first time. As the US was about to enter World War I and needed an efficient method to classify over two million recruits, IQ tests found their first practical use in selecting individuals. Regrettably, this would begin a sad history for IQ tests, with instances like the US State of Virginia's sterilization and Nazi Germany's resolution to exterminate children with low IQs.

Despite the appeal of quantifying phenomena, using improper metrics can lead to disastrous consequences. Since those early days, our understanding of intelligence has evolved significantly. For example, we now acknowledge multiple types of intelligence—such as creative and emotional—not represented by IQ tests. We also recognize that intelligence is not a fixed attribute but can be developed and enhanced, and that’s where the most important focus should be.

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