Addressing the points made by Ingraham, we are pleased to hear further confirmation of reports relating brain computed tomographic density to brain size, and agree with the need to normalize data accordingly.
We appreciate the letter by Zipursky et al, which draws attention to a number of important issues regarding the hypothesized relationship between socioeconomic status (SES) and brain size. These have engendered previous debate in the Archives.1 Historically, this issue has been difficult to examine objectively, often generating more heat than light. First, it tends to bring our ideas on fairness and justice to the fore. Second, much nonobjective "science" has clouded attempts at assessment to date.1 We accept that the study by Hooton2 is far from methodologically strong, but little other objective evidence has been gathered. We also agree with Zipursky that "current evidence supporting a primary relationship between SES and brain size in general