According to Matthews, Tabery, & Turkheimer (2025), our Admixture in the Americas project is “abhorrent” because nothing good could come from investigating “alarming hypotheses regarding the genomic basis of differences in cognitive abilities between racial and ethnic groups.” While Eric Turkheimer’s position is predictable given his well-known motivations, it is surprising to see philosophers like James Tabery also resorting to sloppy, moralistic reasoning. Notably, in the two Admixture in the Americas papers cited by Matthews et al. (2024), we explicitly stated that our research does not test a genetic model. Instead, drawing on Putterman and Weil’s Post-1500 Population Flows and the Long-Run Determinants of Economic Growth and Inequality and a large body of “deep roots” economic literature, we examined a genealogical model, recognizing that various factors could explain the intergenerational transmission of differences. In The Genealogy of Differences (2016), responding to a critique from Ibarra (2016), we elaborated:
According to [our model], intergenerationally transmitted factors such as genes, epigenes and culture code for individual-level traits related to individuals’ ability to acquire knowledge and to develop better societies (e.g., a cultural appreciation of education and learning affecting the development of cognitive abilities). By this model, BGA acts as a crude index of the lines of descent along which the individual-level traits, the true causal factors, are passed… to deny a priori the possibility of our model, Ibarra equates an intergenerational model with a behavioral genetic one and then, incredibly, adopts a Blank Slate position. This is, of course, a doubly absurd argument. First, we stipulated that our model was an intergenerational, or genealogical, transmission, and not necessarily a behavioral genetic one. We made that point in three separate sections of the [original] paper.
