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My WSJ Review of Flynn's Are We Getting Smarter?

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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 general interest 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.

COMMENTS (7 to date)
roystgnr writes:

Being scientific doesn't mean knowing more facts about observations scientists have made or about the theories which explain those observations; in this context it means being more comfortable with the processes of logical deduction and induction which can be used to effectively create and test such theories based on such observations.

Now, I'm not at all convinced that the latter quality has improved in the general population either, but whether it has or hasn't won't be directly discernible from a trivia contest, not even if the trivia questions came from science textbooks whose content every adult ought to be able to understand.

roystgnr writes:

Looking at the GSS questions, there actually is one that asks about a core aspect of the scientific method rather than just about scientifically-obtained facts. And the percentage of people who identified an experiment-with-control-group as being better than one without and who could also explain why is rising by roughly one percent per year.

Steve Sailer writes:

"And the percentage of people who identified an experiment-with-control-group as being better than one without and who could also explain why is rising by roughly one percent per year."

Thanks. That sounds roughly in accord with my subjective sense of the last 40 years: the weight of science documentaries on TV and the like is slowly accumulating, which is good.

gwern writes:

roystgnr: which is?

Luke Carlson writes:

What's the difference between analytic intelligence and verbal intelligence? How are they measured?

lemmy caution writes:

Flynn's article in the wsj was interesting:

The mind-set of the past can be seen in interviews between the great psychologist Alexander Luria and residents of rural Russia during the 1920s—people who, like ourselves in 1910, had little formal education.

Luria: What do a fish and crow have in common?

Reply: A fish it lives in water, a crow flies.

Luria: Could you use one word for them both?

Reply: If you called them "animals" that wouldn't be right. A fish isn't an animal, and a crow isn't either. A person can eat a fish but not a crow.

The prescientific person is fixated on differences between things that give them different uses. My father was born in 1885. If you asked him what dogs and rabbits had in common, he would have said, "You use dogs to hunt rabbits." Today a schoolboy would say, "They are both mammals." The latter is the right answer on an IQ test. Today we find it quite natural to classify the world as a prerequisite to understanding it.

Here is another example.

Luria: There are no camels in Germany; the city of B is in Germany; are there camels there or not?

Reply: I don't know, I have never seen German villages. If B is a large city, there should be camels there.

Luria: But what if there aren't any in all of Germany?

Reply: If B is a village, there is probably no room for camels.

The prescientific Russian wasn't about to treat something as important as the existence of camels hypothetically. Resistance to the hypothetical isn't just a state of mind unfriendly to IQ tests. Moral argument is more mature today than a century ago because we take the hypothetical seriously: We can imagine alternate scenarios and put ourselves in the shoes of others.

People might be ignorant of science but by now most people are familiar with classification of entities by their characteristics instead of by their use. That familiarity can increase measured IQ by several points.

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