London's mayor, Boris Johnson, got himself in hot water last week with the following politically incorrect remark:
Like it or not, the free market economy is the only show in town. ... No one can ignore the harshness of that competition, or the inequality that it inevitably accentuates; and I am afraid that violent economic centrifuge is operating on human beings who are already very far from equal in raw ability, if not spiritual worth.
Whatever you may think of the value of IQ tests, it is surely relevant to a conversation about equality that as many as 16 per cent of our species have an IQ below 85, while about 2 per cent have an IQ above 130. The harder you shake the pack, the easier it will be for some cornflakes to get to the top.
And for one reason or another – boardroom greed or, as I am assured, the natural and god-given talent of boardroom inhabitants - the income gap between the top cornflakes and the bottom cornflakes is getting wider than ever.
Johnson was attacked for daring to say out loud that there's a correlation between IQ and income/wealth inequality. Most commentators cited a 2007 paper by Jay Zagorsky that supposedly refutes Johnson's claim.
But I'm not so sure. I think most commentators privately agree with Johnson, and their mock outrage is simply to enflame their readers.
First, you should read the Zagorsky paper yourself and reach your own conclusion. Contrary to reports, Zagorsky's analysis actually shows a strong correlation between IQ and income/wealth before he fudges the numbers by "controlling for other variables". In doing so, he muddies the result. Let me explain. Imagine a study that shows that men are, on average, physically stronger than women, then controls for shirt size, and comes to the conclusion that women are just as strong as men! Since shirt size is probably linked to the outcome being measured (physical strength), by controlling for it you falsely skew the result.
Second, I believe Johnson is admirable in trying to identify root causes of inequality, regardless of political correctness. If inequality in income and wealth results from differences in IQ (that are beyond your control), let's do something about it, not attack the messenger. I believe that other innate qualities like temperament, energy-level and drive are more important than IQ in explaining natural inequality, but the point remains. If we accept that natural inequality is true, it justifies more income re-distribution and higher taxes on the wealthy to support the poor. To say otherwise and fall back on political correctness just makes inequality worse.