Scott Alexander defends the validity of intelligence and IQ tests by comparing them to comas and the Glasgow Coma Scale in medicine.
Longer summary
Scott Alexander argues that intelligence and IQ tests are valid concepts, analogous to comas and the Glasgow Coma Scale in medicine. He contends that whether there's a single general factor of intelligence is less important than the usefulness of IQ as a predictive measure. Scott draws parallels between how comas and intelligence are measured, showing that both involve multiple factors combined into a single scale used for predictions. He criticizes arguments against the existence of intelligence as often being a motte-and-bailey fallacy, where the easily defensible position (uncertainty about a single general factor) is used to imply that all claims about intelligence are meaningless.
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