Over on Discover gnxp, Victor said “As far as IQ is concerned, I find such comparisons meaningless. An IQ test devised by members of some African tribe is going to be very different from one devised by Western academics. And I can guarantee that most “Caucasians” would not do very well on such a test.”

I mention this not because it is true or sensible, but rather because it is often said. I can hardly count the times that I have seen someone make this argument. The person putting it forth usually thinks of it as utterly crushing. Another related argument is that there are ‘lots of different kinds of intelligence” – so who can say what really matters?

Well, I can. IQ, as measured by IQ scores, is a decent measure of the cognitive skills that you need in order for technical innovation or more routine science and engineering. It’s generally useful in modern technical civilization. Populations with low average IQ produce very few individuals that are good at innovation. Very few. If there were one or a few kinds of intelligence that were not measured well by IQ tests, but allowed people with low IQs to accomplish remarkable things – you’d think we would notice. We know that they don’t invent railroads or transistors or penicillin: what comparably important and useful things have they done?

Look, if magic worked, and was the product of these other kinds of intelligence, I’d revise my opinion. That’s why Henry should have let the witch doctor turn him into a frog: we could have really learned something.

Let us suppose that Victor is right, and that the typical European or East Asian would do worse than average, if raised from babyhood among Australian Aboriginals some 20,000 years ago. Probably no IRB would approve this, and I hear that the Hays Office doesn’t approve of the naked singularities required for time travel, but let us suppose it. So what? Victor has made a prime philosophical and practical error. He is saying that an entirely hypothetical environment, one that does not exist, is comparably important with life its own self. We live here and now, not back then, or in one of the worlds of if. In this world, the one we actually occupy, certain traits help you succeed. IQ tests have value in measuring a certain subset of those traits.

IQ pays off in technical civilization – in terms of wealth, health, and power – and that’s the only civilization left, really. I’m not holding my breath for the Sentinelese takeover.