Bosh, Bosh, me kill big straw man

Alex Tabarrok, in noting the effect of leaded petrol fumes on the intelligence of children can't quite resist another sly semi-endorsement of Lynn and Vanhanen's discredited book: IQ and the Wealth of Nations:

Ever notice that the politically correct attack any discussion of IQ as unscientific and racist, until the discussion turns to lead? Merely mention lead and the liberals will readily quote studies (for once correctly) showing that even low levels of lead can reduce the IQ of children by 4 to 7 points. For some reason, the objections of test bias, multiple intelligences, and racism disappear in this context.

Now, Tabarrok is a very smart guy, much smarter than I am but I am utterly perplexed at the simplistic, illogical argument profferred here. If it is the case that those who have discovered the correlation between leaded petrol and IQ adopt a similar blend of sloppiness, fabrication and tendentiousness in collating their data as Lynn and Vanhanen did with their "data", they deserve similar opprobrium. If they didn't, then it doesn't make any sense to complain about the objections to Lynn and Vanhanen. The question ought to be: Is the data reliable, does it demonstrate the correlation? Tabarrok apparently fails to realise that, at least in the case of Lynn and Vanhanen, the "politically correct" attack them from solid ground.

Comments

[Abiola Lapite]

You give Tabarrok too much credit when you say

Tabarrok is a very smart guy, much smarter than I am

How smart can the guy be if he fails to realize he's just committed the Tu Quoque fallacy? That he has a certain competence within his narrow field is no sure indicator that his intellect is similarly powerful when directed at anything else.

[Frank McGahon]

Perhaps. I think there is a trap into which it is easy to fall into when discussing intelligence, which is to mistake the useful shorthand of considering it as a single, strictly measurable quality (analogous to, say, height) for a complete theory of intelligence. This is perhaps analogous to the trap of assuming intelligence doesn't exist because it is multifaceted. Debunking the notion that IQ tests measure nothing doesn't in itself prove that IQ tests measure all of intelligence. Ironically, given his undoubted expertise in his field, Tabarrok's error here would tend to bolster the "multiple intelligence" theory he blandly disparages!