Questions of the Day and of the Fray number 5: Pearson, Karl. 1912. Social Problems: Their Treatment, Past, Present and Future, A Lecture Delivered at the Galton Laboratory for National Eugenics, March 19, 1912 (London: Dulau and Co.). 40 pp.
Summary
This 1912 lecture advocates that the future of sociology must be built upon the foundation of “measurement and number”, criticizing social policies derived from sentiment, authority, or faulty statistics. Pearson illustrates common statistical blunders with several case studies:
- Imbecility and Vintage: Pearson attacks the widely held medical belief (cited by Professor Forel and Dr. Saleeby, among others) that the wine vintage season produces an “enormous conception of idiots” due to alcohol’s toxic effect on germ cells. Using Swiss birth data, Pearson shows that the slight increase in October conceptions of imbeciles is negligible—just three extra cases beyond expectation—a number “well within the limits of random sampling”.
- Housing and Growth: He refutes the Glasgow finding (Mackenzie and Foster) that children from one-roomed houses were vastly smaller than those from four-roomed homes. This association was revealed to be a statistical fallacy caused by the over-representation of younger children in the one-roomed dwellings. When statistically corrected for age, the extreme difference in weight dropped significantly (from 11.7 lbs. to 5.5 lbs. for boys), demonstrating that simple correlation confused age with housing effect.
- Inebriate Reformatories: Pearson dismisses the notion that the fall in female drunkenness apprehensions in Greenock was caused by the local reformatory. By comparing Greenock’s reduction with the nearly identical (or larger) reductions seen in Paisley and Leith (which lacked reformatories), he concludes that the cause was general (e.g., economic changes) and not the specific institution—a clear case where the belief that “association is causation” led to flawed legislative recommendations.
Questions of the Day and of the Fray number 5
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