My review of James Flynn’s Are We Getting Smarter? is in today’s Wall Street Journal.  Highlights:

When most people hear about the Flynn effect, they conclude that we
really are getting smarter. Mr. Flynn is more cautious. He opens the
book by reviewing his previous work on intelligence tests. IQs have
risen, but we’re definitely not smarter across the board. We’re better
with puzzles and similarities but not better at arithmetic. Vocabulary
and general information have risen for adults but barely budged for
children.

If you still want to say that people
are “smarter” than they used be, Mr. Flynn doesn’t object, but, he
writes, “it would probably be better to say that we are more modern.”
Modern humans, he explains, see the world through what Flynn calls
“scientific spectacles.” We are comfortable with abstract
classification, logic, and hypotheticals–including, Mr. Flynn suspects,
moral hypotheticals.

A nice story, but it has a glaring hole:

The author is confident that rising IQs reflect our greater use of
“scientific spectacles.” Yet the General Social Survey and other studies
of scientific knowledge show that most American adults are
scientifically illiterate. On true-false tests, they correctly answer
60% of basic questions–barely better than chance. Their grasp of
scientific method is similarly dismal. How can science explain rising IQ
if we know virtually no science?

The most eye-opening chapter for me – and probably most gripping for general readers – will be Flynn’s evidence on the effect of aging on intelligence.  The scoop:

What becomes of low- and high-IQ adults when they’re old? The answer is
complex. Verbal intelligence peaks in middle age, then slowly declines.
But there is a substantial “bright bonus”: People with high IQs decline
far less than people with low IQs. If you’re in the top percentiles of
the population, your verbal intelligence will be about as good in your
80s as it was in your teens. For analytical intelligence, however, there
is a massive “bright tax.” People peak in their teens, then decline.
The higher their initial IQ, the greater the atrophy. The most
analytically powerful teens end up being the most analytically powerful
retirees, but even the brightest eventually become mediocre.

To be honest, Are We Getting Smarter? could have used a hard-nosed editor.  Flynn has definitely written better books.  But the top one-third of the material is well worth the price of admission.  As I say in the conclusion:

Few readers will agree with more than half of Mr. Flynn’s closing
observations. All, however, are food for thought. If Mr. Flynn’s
explanation for rising IQ is right, he isn’t merely explaining mankind’s
mental evolution. Reading–and critically evaluating–Mr. Flynn actually
makes us smarter. Or at least more modern.