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
(see Diagram). Should we be alarmed?
It will be several more years before we can be certain of the new trend, but
even if the dip is sustained for decades to come it won’t spell catastrophe for
intellectual life. Far from it. Take the IQ rise of recent decades at face
value, and the average child today should be as bright as the near genius of
yesteryear. So where is the unparalleled renaissance this should have brought
about? The fact that there hasn’t been one powerfully exposes the limitations of
IQ as a proxy for intelligence.FIG-mg23320101.jpg
Kids today may well be geniuses at solving the sort of abstract on-the-spot
problems that dominate IQ tests. But the way the world has shaped up indicates
this to be a narrow, perhaps even trivial, aptitude. True, recent decades have
seen ever younger chess grandmasters and greater scientific productivity. But
rising IQs are unlikely to be fuelling such trends. The financial rewards for
exceptional talent in any sphere, including chess, are much greater than they
were. And today’s scientists are under far more pressure to publish.
Advertisement
Even if we wanted to intervene to keep IQ scores on an upward track it is not
obvious what we could do. That’s because the cause, or causes, of the IQ rise
remain a mystery. Better nutrition? Children born into the severe Dutch famine
of 1944 did not miss out on the rising IQ curve. Better education? The gains are
missing or small on the kind of IQ tests closest to school-taught material.
In recent years the IQ rise has been variously attributed to visual
stimulation from cartoons, crowded computer screens, video games, even fast-food
place mats and cereal boxes smothered in word games and mazes. But all this is
speculation. Nobody has a shred of empirical evidence that any of these
influences actually boost IQ. A century ago, scientists developed simplistic
ideas about racial differences in IQ scores and ended up providing ammunition
for the Nazis and other eugenicists. This century’s IQ experts must take care
they do not manufacture undesirable ammunition of a different kind. In an ever
more complex world, it is inevitable that brain power should become more highly
valued and perhaps increase in certain ways. Fast food chains and the consumer
electronics industry neither need nor deserve the credit for bringing it about.
