# Kathryn Paige Harden and the Myths of Genetic Determinism
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Chapter 1: Introduction to Genetic Determinism
Recently, Kathryn Paige Harden, alongside James Madole, published a paper in Behavioral and Brain Sciences that highlights a critical distinction within the genetics community. Their aim appears to be to categorize certain genetic researchers as "supra-causal," a term synonymous with determinism. This is the same Harden who wrote The Genetic Lottery: Why DNA Matters for Social Equality. Although I sensed this was her underlying agenda in the book, I don't recall her explicitly differentiating her perspective from that of the so-called supra-causal geneticists. One of the researchers they critique is Robert Plomin. However, there are discrepancies in how Harden and Madole portray these geneticists, and while I can substantiate this point, their broader goal of excluding some geneticists for credibility's sake remains unverifiable. Their approach essentially states, "We're not like those geneticists; we're the credible ones!" Here’s why their paper fails to draw the intended distinction.
Section 1.1: The Misunderstanding of Plomin's Views
Harden and Madole claim that Plomin views genes as supra-causal. Yet, they dedicate insufficient time to defining this term, leading to a failure in distinguishing their causal model from Plomin’s. The confusion arises because Plomin discusses genetic causes in terms of populations rather than individuals. While I believe both Harden and Madole are aware of this nuance, they seem to misrepresent Plomin’s population-level discourse to mischaracterize his position. According to Harden and Madole, their model asserts that genes are shallow causes: “[…] they operate within intricate causal systems (non-unitary), produce heterogeneous effects across individuals (non-uniform), and are not mechanistically informative (non-explanatory).”
If you’re familiar with contemporary geneticists beyond Herbert Spencer, you may recognize the flaws in this definition.
Subsection 1.1.1: Why Their Definition Lacks Substance
Their framing presents a false dichotomy between two ideologies: the supra-causal and the non-causal. This represents a classic fallacy of moderation, mistakenly suggesting that the middle ground is inherently correct simply because the extremes are deemed untenable. Furthermore, there is no real separation between their views and those they mischaracterize as supra-causal, given that Plomin does not subscribe to the notion that genetic causes are unitary, uniform, or explanatory. Plomin has consistently clarified that he does not believe genetic causes are singular, as evidenced by his assertion that teaching basic skills can largely mitigate environmental disparities, indicating that he does not view genes as the sole determinants.
Plomin also refutes the idea that genetic effects are uniform across individuals, as illustrated by his tenth law of behavioral genetics, which states that “abnormal is normal.” In his foundational paper, he elaborates on how many clinical traits arise from the interplay of multiple genes, rather than being attributable to a single genetic factor. Therefore, the introduction of an additional gene may influence someone who possesses many genes for a particular trait differently than it would affect someone with fewer genes for that trait.
Moreover, Plomin posits that polygenic scores are probabilistic rather than deterministic predictors. He acknowledges the existence of individual variations across different levels of these scores. Would Harden argue that Plomin would dismiss environmental factors, like exposure to certain substances and its link to schizophrenia, as having no causal role? It’s unlikely.
Chapter 2: Evaluating the Integrity of Harden's Argument
After reviewing Harden and Madole’s article, I find it challenging to differentiate Plomin’s actual causal framework from theirs based on the criteria they present. Their mischaracterization of Plomin’s beliefs leads to the construction of a deterministic strawman. Even Charles Murray’s stance on genetic causation remains ambiguous, contrary to Harden’s claims. Notably, Plomin himself has stated that Harden misrepresents his views.
Why Would Harden Misrepresent?
The final point of consideration is the motivation behind the claims made by these well-respected researchers. If they genuinely believe their statements, the implications are even more troubling, given the depth of misunderstanding exhibited. It seems plausible that Harden aims to address the left's concerns regarding genetics, particularly the criticisms associated with genetic determinism, which often evoke fears of eugenics. In response to these concerns, some geneticists feel compelled to draw a line between their own beliefs and the extreme determinist views held by others.
However, this approach is flawed; as discussed, Harden’s distinctions fail to hold up, and her causal model does not significantly differ from those she aims to critique. The term "supra-causal" itself closely aligns with determinism, and it is widely recognized among serious researchers that Plomin does not endorse a deterministic view of genetics.
While we should consider Harden’s motivations for her writings, it is crucial to approach her opinions with scrutiny, especially given her repeated assertions across various platforms, much like Plomin.
References
1. Herrnstein, R. J., & Murray, C. A. (1996). The bell curve: Intelligence and class structure in American life (1st Free Press pbk. ed). Simon & Schuster. 3. Madole, J., & Harden, K. (2022). Building Causal Knowledge in Behavior Genetics. Behavioral and Brain Sciences, 1–76. doi:10.1017/S0140525X22000681 4. Plomin, R. (2018). Blueprint: How DNA makes us who we are. The MIT Press. 5. Plomin R, DeFries JC, Knopik VS, Neiderhiser JM. Top 10 Replicated Findings From Behavioral Genetics. Perspectives on Psychological Science. 2016 Jan;11(1):3–23. doi: 10.1177/1745691615617439. PMID: 26817721; PMCID: PMC4739500. 6. Plomin R., Long B., Personal Communications, June 2022.