As school returns, I am hearing comments about “intelligence” return to my media feeds and in chatter amongst people who purport knowledge of teaching and learning. This seems a good opportunity to post again on the dubious evidence if IQ as it is commonly understood.
For decades, IQ tests have shaped perceptions of intelligence, often with profound societal impact. However, a closer look at the history and underlying philosophy of these tests, as explored in Stephen Jay Gould’s The Mismeasure of Man, reveals critical flaws that undermine their claims of objectively measuring innate mental worth. The core argument against IQ testing, as presented by Gould, centers on the reification of intelligence – turning a complex, socially defined concept into a single, quantifiable, innate entity, and the subsequent misuse of these numbers to rank individuals and groups.
Alfred Binet, the French psychologist who developed the original scale, never intended for it to be used this way. His primary, benevolent purpose was to identify children in need of special educational help, explicitly rejecting the idea that his scores represented anything innate or permanent. He believed that the human mind was flexible and that educational intervention could effectively improve deficiencies, strongly protesting the “brutal pessimism” of those who claimed intelligence was a fixed quantity. Binet recognized that the scale “does not permit the measure of intelligence because intellectual qualities are not superposable”.
However, in America, Binet’s intentions were “dismantled” and “overturned” by hereditarians like H.H. Goddard and Lewis M. Terman. Terman, who developed the widely used Stanford-Binet IQ test, explicitly defended the innatist view and reified average test scores as a “thing” called general intelligence. This American interpretation became foundational to the belief that IQ measures a unitary, genetically based, unchangeable intelligence.
Further invalidating these tests is their inherent cultural bias. The Army Mental Tests during World War I, for example, were presented as measures of innate intelligence but were effectively an “index of familiarity with American culture”. Critics like Walter Lippmann observed that such tests often stressed conformity over original response, and the data itself was “finagled” to support predetermined conclusions, ignoring clear correlations with environmental factors.
The political impact of this mismeasure has been significant and harmful. It has been used to justify social hierarchies, promote policies like restricting immigration based on perceived “race deterioration,” and dismiss compensatory education programs. Gould argues that such deterministic arguments merely record “social prejudice” rather than objective scientific fact.
Ultimately, the argument against IQ testing, particularly its hereditarian interpretation, rests on the understanding that human intelligence is a diverse set of “largely independent abilities,” not a single, immutable, inborn “thing-in-the-head” that can be ranked on a linear scale.