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Which Environmental Factors Explain the Black–White IQ Gap?

Source: Aporia Magazine \ Author: Noah Carl \ Date Published: 2024-11-29

TL;DR

Noah Carl's piece critiques a PNAS paper by Kevin Lala and Marcus Feldman that equates the hereditarian hypothesis with racism. Carl argues that while Lala and Feldman dismiss hereditarianism as having "no scientific evidence," they do not provide a compelling environmental alternative — i.e., a specific, evidence-backed theory of which environmental factors explain racial IQ gaps. The article is a challenge to environmentalists to produce positive evidence, not just critique.

Core Argument

The article opens by noting that every so often, an academic paper is published that equates hereditarianism with racism. The latest example is Lala and Feldman's paper in Proceedings of the National Academy of Sciences, titled "Genes, culture, and scientific racism."

Key quotations from Lala and Feldman's paper that Carl highlights:

  • They refer to "racist claims of ubiquitous genetic differences between socially defined races."
  • Such claims, they argue, "help to perpetuate racist ideas."
  • They state that Cochran and Harpending's theory of Ashkenazi Jewish intelligence has "racist underpinnings."

Lala and Feldman assert that "there is no scientific evidence that supports the claims of Shockley, Jensen, Herrnstein, Murray, and other hereditarians that there are substantial genetic differences in intelligence between races."

Carl's Challenge

Carl's central point: if hereditarianism is to be dismissed so sweepingly, there must be a compelling environmental alternative. Lala and Feldman, he argues, do not provide one:

  • They did not identify specific environmental factors (e.g., nutrition, education quality, stereotype threat, lead exposure) that can fully account for the measured IQ gaps.
  • They did not provide empirical evidence showing that controlling for those factors eliminates the gaps.
  • In the absence of a positive environmental theory, dismissing hereditarianism as merely "racist" is an argument from authority rather than evidence.

Significance

The piece sits at the centre of the long-running nature-nurture debate in intelligence research — a field with profound implications for education policy, social justice, and scientific methodology. Carl's critique highlights what he sees as a double standard: environmental explanations are presumed correct despite lacking the same level of specificity that hereditarian theories are criticised for.

Note: This article was behind a paywall; the summary is based on the publicly available introduction and framing sections.