 Lewontin (2006) later adds “The point of the (1974) paper was to explain why the statistical partitioning of observed variation in phenotype into variance associated with variation in genetic relationship as opposed to variance assigned to environmental dissimilarities does not, in fact, separate genetic and environmental causes in development” (2006, 536). He adds that advances in molecular genetics now make it “possible to provide a detailed molecular analysis of the chain of causation between nucleotide substitution and cell development and function” (Lewontin, 2006, 536). (Sober (1988) also emphasizes this aspect of Lewontin’s criticism of the analysis of variance.) Lewontin makes clear what he takes genetic causation to be: the causal chain from a DNA sequence to a protein product taking place within cells of organisms. His point is that statistical methods of population genetics and behavioral genetics alone are not appropriate to the task of revealing genetic causes construed this way. We revisit this issue in Section 5. recast in light of GWAS and other “molecular” techniques of measuring heritability.