> Surely IQ is measuring something useful if it correlates so well with things like job performance, school performance, income, and crime? It might be just co

> Surely IQ is measuring something useful if it correlates so well with things like job performance, school performance, income, and crime? It might be just correlating to zip code. We know poorer neighborhoods in the US have vastly higher rates of lead which has negative effects against IQ and violence. I've seen far more evidence against the concept of a general intelligence than for.