Hereditarianism: a progressive research program

I am posting this because this is not widely known, but I think this angle should be taken more seriously. I hope philosophers will read this and get inspired!

Peter Urbach (this guy, not this guy!) was a student of Imre Lakatos, and in 1974 he wrote a frank assessment of the status of the contrasting research programs in psychology: the hereditarian program and the environmentalist one. Hereditarian here is concerned with genetic causation in general not limited to between group differences. There is no abstract, but part one opens with:

In the question of intelligence, all roads lead back to the work of Francis Galton in the late nineteenth century. He was the first to formulate a theory of ‘general intelligence’ 1 ; he pioneered the construction of mental tests; and he was the inventor of experimental methods for investigating the inheritance of mental abilities.

The controversy between those who hold that individual and group differences in intelligence test scores are primarily due to inherited differ- ences and those who hold they are primarily the products of environmental differences is one of the oldest and most acrimonious in social science. The controversy has been ahnost universally marred by a lack of clearly defined standards by which to assess the rival theories. Whenever such standards have been invoked, they have been either Utopian 2 or unsatis- factory. 3

I intend to describe and appraise the rival views of intelligence in terms of Lakatos’s methodology of scientific research programmes and thereby to evaluate the two competing programmes in the light of their objective merits. This will also detach the debate from the political positions with which they are falsely associated in the public mind.

My thesis is that the hereditarian-environmentalist rivalry has existed not between two competing theories but between two competing research programmes. For there have been a series of—falsifiable and, indeed, falsified—hereditarian and environmentalist theories, each term in each of the two series dealing with some of the refutations (or anomalies) faced by its predecessor. Each of the two series can be characterised by a set of assumptions (‘hard cores’) common to all the terms. Moreover, each of the series is associated with certain ‘heuristic’ machinery guiding the con- struction of successive hypotheses in the series. Thus both the hereditarian and environmentalist approaches possess all the features identified by Lakatos in major physical scientific research programmes. 4

And his conclusion of part one:

The hereditarian programme has anticipated many novel facts. I have discussed the successful predictions (t) of the degree of family resemblances in IQ B , («) of IQ-related social mobility, 6 (Hi) of the distribution of IQ’s, and (iv) of the differences in sibling regression for American Negroes and whites, 1 since these are the most striking examples. When the environ- mentalist programme has attempted to account for the novel facts produced by the hereditarian programme, it has been unable to do so except in an ad hoc fashion. The hereditarian programme is not free from anomalies— but in this respect it is not exceptionally placed among scientific research programmes. Anomalies are anticipated by a good research programme and the puzzle-solving techniques for resolving them are articulated in advance. The crucial criterion for deciding whether a programme is progressive is whether it has anticipated novel facts. By this criterion, the hereditarian programme has been scientifically progressive and has contributed to the growth of knowledge. 2

This is even more true now than when it was written in 1974. The era of genomics has vindicated yet more predictions from the hereditarian program: 1) polygenic nature of intelligence and other traits, 2) mostly additive genetic effects (failure of especially GxE and also GxG research to substantiate claims), 3) newer methods to quantify heritability find substantial estimates (GREML and friends), 4) a decline in polygenic scores over time i.e. dysgenics was confirmed in multiple studies, 5) many more decades of environmentalist ad hoc claims, 6) general agreement now that brain training programs do not work, 7) failure of colorism model in empirical tests, 8) large scale studies of enrichment programs/early intervention failing to find lasting benefit (fade-out) and initial small gains, 9) replication crisis finding massive issues with mainstream and environmentalist research, but not hereditarian research. One could list more.

There is a pressing need to write an update on the Urbach papers. Rushton and Jensen (2005) mentions it but did not expand on it.

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