Aaron Rosanoff had adjusted the definition of mental illness to make his inheritance calculations more accurate in order to justify the sterilization of the mentally ill
The scientific justification for the compulsory sterilization of the severely mentally ill rested on two premises: that “insanity” was an inherited disease and that the severely mentally ill were proficient at the mating game and thus were passing on their tainted genes to a large number of offspring. If either of these facts were not true, then the eugenicists’ argument that the mentally ill were a threat to the country’s “germ plasm” would be seriously undermined.
Proving that insanity was an inherited disease fell to Aaron Rosanoff, a doctor at Kings Park State Hospital in New York. Working under Charles Davenport’s tutelage, he charted the family histories of seventy-two insane patients. His initial results were not what he expected. Among the 1,097 relatives of the seventy-two patients, only forty-three had ever been hospitalized for a mental illness—a number far too low to show a causal genetic link. Rosanoff calculated that according to Mendelian inheritance, 359 of the relatives should have been mentally ill. His study seemed to disprove the notion he’d set out to prove. Where had he gone wrong?
The answer, he concluded, was that he had defined mental illness too narrowly. Plenty of mentally ill people were never hospitalized. Thankfully, the threshold for diagnosing mental disorders are somewhat arbitrary and can be adjusted. “Neuropathy,” he explained, manifested itself in many ways. Relatives of patients with manic-depressive insanity should be considered mentally ill if they were “high-strung, excitable, dictatorial, abnormally selfish,” or if they had an “awful temper, drank periodically, [or] had severe blue spells.” In a similar vein, relatives of patients hospitalized for schizophrenia should be classified as neuropathic if they were “cranky, stubborn, nervous, queer, [or] restless,” if they were “suspicious of friends and relatives,” if they “worried over nothing,” or acted like “religious cranks.”
And with that neatly expanded definition of mental illness at work, Rosanoff determined that the seventy-two hospitalized patients had 351 neuropathic relatives—almost an exact match to the number needed to support his hypothesis. “The hereditary transmission of the neuropathic constitution as a recessive trait, in accordance with the Mendelian theory, may be regarded as definitely established,” he happily concluded. When we mistake our models with reality itself, we stifle our capacity to learn new ideas.
References
- Whitaker, Robert. (2002). Mad in America Chapter 3. UNFIT TO BREED (p. 81). New York, NY: Basic Books.
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Type:🔴 Tags: Biology / Psychiatry / History Status:☀️