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WHATEVER it is that IQ tests measure, we’ve been getting progressively better
at doing them for several decades. Political scientist James Flynn identified
the trend in the 1980s, and since then the evidence for rising IQs has grown as
relentlessly as the test scores themselves. Alas, nothing lasts forever. This
week we report the first evidence that the era of booming IQ growth is over
(see “Brain gain”).
Indeed, a pessimist scanning the latest figures from Denmark, a country
noted for its detailed IQ records, might conclude that average IQs have not just
peaked but are heading back down…