Archive for November 2007

Racial Realism and Pipe Dreams

November 28, 2007

Slate embarrasses itself with its article here, which is based almost exclusively on this paper here.

To start off, Rushton and Jensen have a methodology that is not conducive to making the sort of strong claims on genetic correlation they want to make. The worst part is their conclusion, where they take their hypothetical 50-50 split between nature and nurture and tilt it all the way up to 80-20 in favor of heredity. By their own data, the impact of better education and environment has an average minimum 10 to a maximum 20 point effect on IQ, which would totally eliminate or nearly close the gap between blacks and whites. Also by their own data, the IQ impact of programs to improve those factors are strongest in childhood but diminish during adolescence. I guess they could deny that adolescence is the time of individual awakening to cultural roles and expectations, but it would be a ludicrous position. What they conjecture instead is that genetic phenotype asserts itself over cultural influence at puberty. So basically, flip a coin and heads it is genetics or tails it is genetics.

To his credit and my dismay, the conservative Thomas Sowell has documented and criticized the strong cultural bias of IQ tests. Despite that, Rushton and Jensen ascribe the difference between the average IQ of African and American blacks to racial interbreeding with whites. Because obviously, no difference between African and American environment. Also, IQ is based upon a small number of genes which are recombined in a simple fashion.

Flynn has documented that racially averaged IQ is not a stable phenomenon. All groups are making increases relative to their past performance, but also relative to other groups there are changes that have taken place. Rushton and Jensen don’t delve into this, but the role of environmental factors like malnutrition have a statistically significant effect on health up to two generations later. It would not be speculative on my part to assume that those factors could carry forward in a similar manner upon development of traits, which would skew the data between environmental improvement and substantial IQ changes by forty years or so.

The whole thing on brain size and/or weight is straight out of pseudoscience 101. As Einstein’s brain showed, structure matters exponentially more than quantity of brain tissue. That is the materialistic rebuttal of the argument, which oddly enough might be prone to a genetic cause. If you believe in strong dualism, the connection between immaterial mind and brain is irrelevant to begin with. If you believe in functionalism, IQ is a complex phenomenon with a large number of overlapping elements, and it measures only one tile in the total mosaic of social fitness.

Their apparent policy prescription of eliminating affirmative action is based on the premise that degrees of racial inequity are inevitable due to a largely genetic component of IQ. If we lived in a society where only IQ mattered as an obstacle to integration into mainstream culture, their proposal would carry some degree of argumentative force if all their theories were valid.  Since we do not live in that society and their theories are very wobbly to say the least, their proposal is unjustifiable.

My last point of contention is that the percentage of genes involved in ethnic differences are estimated about 1% of the total genome (or one tenth that number if duplicate genes are ignored). Given the intricacies of phenotypes, those genes may actually have an effect on IQ, but I like my odds.

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