I can see how the argument may be confusing . . . Gladwell's mincing words a bit, trying hard not to explicitly call out the racism inherent in the arguments pu

I can see how the argument may be confusing . . . Gladwell's mincing words a bit, trying hard not to explicitly call out the racism inherent in the arguments put forth by some in this tired IQ debate. Allow me to paraphrase the statement, kid-gloves off: There are a lot of pseudo-scientists out there who claim that IQ tests are perfectly accurate, not at all culturally biased, and are in fact objective, innate measures of intelligence. According to these folks, black people are just fundamentally less intelligent than white people, that's why IQ scores are so correlated to race. This theory would predict that "tainting" pure white blood with "intellectually inferior" black blood should yield children who are stupider than their white counterparts, without regard to cultural factors. In practice, though, the evidence appears to point to a more nuanced explanation, as there is a statistically significant difference between IQ scores when cultural factors (such as race and gender combinations of the parents) differ. In other words, IQ may not be statistically independent of the non-genetic factors surrounding the test-taker. That might clear it up. If not, the remainder of the paragraph that you quoted may elucidate it further: "And it shouldn't make much of a difference where a mixed-race child is born. But, again, it does: the children fathered by black American G.I.s in postwar Germany and brought up by their German mothers have the same I.Q.s as the children of white American G.I.s and German mothers. The difference, in that case, was not the fact of the children's blackness, as a fundamentalist would say. It was the fact of their Germanness--of their being brought up in a different culture, under different circumstances."