Which matters more for influencing criminal behavior: nature or nuture? This 1919 paper from England, “the most complete first hand scientific study of the criminal that exists in any language,” found it was nature.

Presenting what seems to be the most complete first hand scientific study of the criminal that exists in any language, it goes a long way toward proving that there is no “criminal type,” and casts grave doubt upon the previously held theory that the criminal is a product chiefly of environment.

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Dr. Goring comes to the conclusion that physical and mental defectiveness, like many other human qualities, is inherited, and he infers that crime is, to a large extent, a product of nature rather than of nurture and environment.

So what indeed determines criminal behavior, according to the study? Primarily inherited mental disorders:

First convictions show a preilection for the age period 15 to 25, which Dr. Goring concludes to be significant. Comparing this fact with the age incidences of liability to various diseases, he is inclined to interpret the facts as evidence that a “mental constitutional proclivity is the primal source of the habitual criminal’s career.”

The nature vs. nurture debate still plagues us today. Coming down on the nature side is the thought-provoking book  Why Beautiful People Have More Daughters by Alan S. Miller and Satoshi Kanazawa. I actually had an email correspondence with Kanazawa after reading his book, and he was very friendly and helpful in elucidating some of his book’s ideas further. Coming down more on the nurture side is the 2018 documentary Three Identical Strangers, which I’d also highly recommend.

Every month I listen to the debate show Intelligence Squared U.S., in which teams of two debate a topic and the audience votes on which side most changed their minds. October’s episode on nature vs. nurture was terrific. I won’t spoil which side won, but the final score was +7% to +5%, one of the closest matches in the history of the show.

Criminal Is a Defective, but Not a Type: Conclusions from Biometrical Study of 3,000 British Convicts Discredit Lombroso’s Theory and Minimize the Influence of Environment

Published: Sunday, December 21, 1919