> Because of all of these confounding factors, it's not really possible to draw any conclusions from what we know to be a bunch of variously flawed studies. To

> Because of all of these confounding factors, it's not really possible to draw any conclusions from what we know to be a bunch of variously flawed studies. To me, the most uncomfortable truth revealed by all this research is how willing some people are to jump at ultimately tenuous research that supports racist preconceptions. This is deeply unfair to psychometrics researchers. For it to be racist the claim would have to be that group differences in mean psychometric differences are overwhelmingly hereditary and so far as I know absolutely nobody with any education on the subject is making that claim. They allow that it could be nutrition, toxin exposure, cultural, or any number of other factors. Nobody credible says it's just heredity because the evidence doesn't support that. Nonetheless, the differences are measurable and persistent.