Questions of the Day and of the Fray number 1: Pearson, Karl. 1910. The Influence of Parental Alcoholism on the Physique and Ability of the Offspring. A Reply to the Cambridge Economists (London: Dulau and Co.). 26 pp.
Summary
The Influence of Parental Alcoholism on the Physique and Ability of the Offspring is part of the Galton Eugenics Laboratory’s “Questions of the Day and the Fray” series. Authored by Karl Pearson, F.R.S., and published in 1910, the work serves as A Reply to the Cambridge Economists.
Pearson addresses criticisms stemming primarily from a review by Mr. J. M. Keynes and opinions voiced by Professor Alfred Marshall, stating that the logic of both Cambridge economists appeared “faulty”. The original Galton memoir utilized Manchester and Edinburgh data to inquire whether temperate and intemperate sections of a population, under common environmental conditions and lacking other initial differentiations, had children that differed widely in physique or mentality.
Pearson strongly defends the integrity of the data, noting that the Manchester material was collected by the capable Dr. Ashby and was as reliable as the Edinburgh Report, which Marshall himself allowed to be of “marvellous excellence”.
The central defense against the critics—who asserted that the study population was exceptional “low grade” or “subnormal” stock—is that they failed to show any differentiation between the temperate and intemperate sections being compared. Pearson provides a detailed analysis of the occupations and wages of the Edinburgh fathers, demonstrating no marked class differentiation. The average wage for a drinker (25s. 6d.) and a temperate father (25s. 5d.) were virtually the same, contradicting suggestions that the drinkers were originally better stock who had fallen due to alcohol.
Pearson also defends the modern statistical methods used, including partial correlation coefficients, which he asserts are necessary to quantify the association between parental habits and filial character. These methods showed only a “very slight but sensible influence” of maternal alcoholism on the daughter’s height and weight, and practically none from the father. Ultimately, Pearson maintains that the critics failed to logically assault the memoir’s position by producing evidence of original differentiation between the two groups.
Questions of the Day and of the Fray number 1
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