Wealth and IQ

A reader writes:

I recently heard on television a college professor and author speaking enthusiastically in favor of affirmative action. When asked about disparity between white and black I.Q.'s even when family household income is controlled for, he replied something along the lines of "You are controlling for the wrong factor. If instead of income you control for family household wealth black and white I.Q.'s are identical." Without any specialized knowledge or training, I have nonetheless followed the affirmative action controversy over the years and don't ever remember hearing this before or hearing this particular tack taken by any of its proponents Do you know if it is true?

This comes up now and then, so let me try to explain how this sleight of hand works:

The implication is that wealth serves as an environmental effect that changes IQ by 15 points (the one standard deviation difference between whites and blacks). But, there's no evidence from any adoption or separated twin study that says that net worth has much impact on adult IQs, so the alleged causal mechanism is not true. Indeed, most of the environmental variation in IQ does not appear attributable to anything measurable in the environment -- it might have more to do with random infections or bumps on the head or developmental differences.

What he's trying to do is find a selection effect where he can select blacks who are, say, two standard deviations above the black mean for IQ and compare them to whites who are one standard deviation about the white mean and then, hesto presto, discover that they are equal in IQ.

Net worth is particularly suited to playing this game. Blacks have a much harder time than whites accumulating wealth (they inherit less, their houses don't appreciate as fast because they tend to live in crime-ridden black neighborhoods, and they save less of their income), so blacks with high net worth are much more elite relative to other blacks than whites with the same positive net worth. So, that's how you get them as having equal IQs.

My published articles are archived at iSteve.com -- Steve Sailer