Thanks, @Bartleby789 . Unlike the Scrivener, you have engaged in this back and forth without a hint of “I’d prefer not to” and many of your points are well taken and have given me some additional sources to look at.
This will be my last post on this particular back and forth, and again I would encourage people reading this exchange to explore the source material itself and make a judgment as to which side has the better argument. It is worth noting in that exploration that no hereditarian makes the argument that intelligence is 100% genetic - every researcher allows for the existence of environmental factors that influence intelligence. Some researchers (e.g., Haier) do believe that intelligence is 100% biological and (perhaps) 100% expressed through genetic factors, but they note that there are complex interactions between genes and environmental factors at various stages of life (epigenetics, for those who are interested).
By contrast, environmentalists must make the difficult claim that intelligence is 100% environmental, in effect that observed group differences are “recreated” each succeeding generation, and hence the search is on for what environmental factors are causing those differences. The stakes are high because, and here I am revealing my own bias, if group differences are environmental we as a society need to focus on narrowing group differences, rather than on optimizing education and intelligence at the individual level (to the extent that we can enhance intelligence through environmental factors - and remember, no hereditarian disputes the existence of such factors). In addition, the stakes are also high for lower-performing groups as well. If genetic factors are important in intelligence, then an emphasis on equalizing environments will actually lead to a widening of, at least, achievement gaps, and perhaps of intelligence gaps themselves (to the extent that intelligence can be altered by environmental effects). This widening will occur because as environmental conditions are equalized, non-environmental (i.e., genetic) factors will predominate. There is some evidence that this is exactly what is happening, and it is directly contrary to the political agenda of the IQ environmentalists.
As for a few specific points brought up. I have seen much of the data presented in the linked Nisbett, et al. article (much is quite old and has been presented in, for instance, Hunt’s textbook “Intelligence”), but I haven’t seen them neatly pulled together in one spot, so thanks! Not to belabor the point, but it is instructive regarding how these debates go to examine how Nisbett “refutes” brain size correlations, as argued by @Bartleby789. He simply ducks the question with the statement that there has been no new “probative” evidence and cites to two of his earlier works. One of those is what I linked to upthread, and here is his “discussion” in there:
“The rest of Rushton and Jensen’s (2005) article consists of reports of brain
size and reaction time correlates and other indirect evidence. If the direct evidence
were not so strongly supportive of a purely environmental explanation of the
Black–White difference in IQ, then such findings would have relevance to an
understanding of the difference. But when direct evidence points so clearly to the
conclusion that there is no hereditary basis for the difference, indirect correlational
evidence has little meaning.”
http://www1.udel.edu/educ/gottfredson/30years/Nisbett-commentary-on-30years.pdf
Note that the correlations for brain size, variously given as 0.4 (Jensen) or as low at 0.32 (Nisbett) are in fact moderately strong evidence. In fact, the entire argument of the environmentalists ultimately rests on some combination of SES variables, which even though always confounded with intelligence, still typically only show correlations of less than 0.4 with intelligence. Reaction time correlations are even higher. Environmentalists simply pick and choose what evidence supports their political agenda.
(The other work cited by Nisbett is one of his books, which not surprisingly was released in 2009 to rapturous praise by the NY Times, among others. For a review of the book’s many deficiencies, see http://laplab.ucsd.edu/articles2/Lee2010.pdf )
Last (I promise), @Bartleby789 argues that the acknowledgement that East Asian mean IQ is higher than Whites is not inconsistent with a “white supremacist agenda” because the difference is only between 1/10 and 1/3 of a standard deviation. Well, in the very first Jensen article I linked to (section 3, p. 240), the standard deviation is given as 4/10 (106 vs. 100, SD of 15; 6/15 = 0.40), so you really don’t have to look very far to see hereditarians positing higher numbers! Moreover, most hereditarians (e.g., Jensen, Rushton, Gottfredson, Harpending, Cochran, Hernstein, Murray and about a dozen others) have no issue noting that Ashkenazi Jews have mean IQ fully one standard deviation above Whites as a group, which is approximately the same size as the Black-White gap. Again, this acknowledgement is difficult to reconcile with a “white supremacist agenda” - perhaps even more difficult than the noted Black-White gap! As you get into the literature, you will find a great deal of implicit name calling by one particular side.
Anyway, this is a fascinating area to explore, much richer than the popular media would have you believe. The policy implications for affirmative action or other “compensatory” programs are not dictated by whether you adhere to a hereditarian view or a 100% environmental view. Personally, I believe that we need to move past recrimination and the belief that any time one group performs better or worse it is somehow the “fault” of another group or of “society.” Such a view is incredibly damaging both to society as a whole, as well as to the very groups that are purportedly being helped.