The conviction that there is a hereditary predisposition to most mental illnesses attracted early on the attention of the leaders of the eugenics movement. Yet, at the beginning of the 20th century, when the first eugenics societies were founded, psychiatric classifications were still in their infancy in the US and in Canada. They consisted of a few broad labels (like the opposition “idiots” vs. “lunatics”) and were primarily used for statistical purposes. With the emergence of psychiatry as a genuine branch of medicine and the progressive social recognition obtained by psychiatrists during the first part of the 20th century, psychiatric classifications underwent a sizeable expansion. Eugenics ideas exerted a subtle influence on this development. They did not directly impact the content of psychiatric classification, but they indirectly influenced its form and the way it should be used.

The early development of psychiatric classification
In the late 18th-century, the development of psychiatric clinical knowledge was closely related to the multiplication of asylums in many European cities, with the influential contributions by authors as different as the French physician and botanist François Boissier de Sauvages, the Swedish botanist, zoologist and physician Carl Linnaeus, the Scottish physician William Cullen, and, later on, the French alienists Philippe Pinel and Jean-Etienne Esquirol. Classification systems of this period, as Michel Foucault has described in Madness and civilization, perfectly echo “the old asylum structure of non-reciprocal observation” (Foucault 1988, 250-251), with its characteristic mixture of broad humanitarian principles and strict surveillance techniques, of knowledge and power. The act of classifying mental disorders also illustrates the persistent effort by alienists of this time to develop a “technology for the enhancement of [their] professional power” (Goldstein 1987, 321).

During the 19th-century, many different nosological systems were proposed by great professors of psychiatry, sometimes at the risk of increasing confusion in the field. Important discussions arose amongst clinicians around the 1850s concerning the main goals and principles of psychiatric classification. Should the divisions inside the classification be considered natural or artificial? And above all, are there various insanities, or is there only one? Benedict-Augustin Morel (1809-1873) played a central role in this debate: he discarded previous classifications based on surface symptoms and sought to establish an etiological classification centered on the idea of the hereditary transmission of insanity (Berrios 1999).

Morel’s hereditary degeneration theory exerted a profound influence in psychiatric nosology, in criminal anthropology, and in popular imagination. The rise of hereditarianism in psychiatry during the following decades encouraged the growing interest of psychiatrists outside the asylums and inside the society (Dowbiggin 1991, 122). In North America, hereditarianism would soon link the concerns of social Darwinists to those of early proponents of eugenics.

Eugenics and the first US statistical psychiatric classification
It wasn’t until the end of WWI that US psychiatrists were provided with their first national reference classification. The Statistical Manual for the Use of Institutions for the Insane was published in 1918 in collaboration between the American Medico-Psychological Association (AMPA) and the National Committee for Mental Hygiene (NCMH). This classification, a forty-page document, aimed at bringing more uniform statistics in the institutions of mental diseases across the territory. The greater part of the manual consists of instructions for how to fill in statistical cards and tables by taking into account variables as diverse as sex, age, degree of education, environment, and marital status. One striking feature of the manual is its special emphasis on racial considerations. At a time when the psychiatric institution is taking an active part in the immigration debate, with the idea of keeping out insane immigrants, racial considerations inside the classification are given the same importance as the medical diagnostic itself. Clinicians are provided with a short “race classification”, and they are sent back to the “excellent” Dictionary of races and peoples (1911) published by the Immigration Commission.

The 1918 manual thus illustrates the moment when the involvement of US psychiatrists with eugenic measures reaches its highest point. Madison Grant’s The Passing of the Great Race has just been published a couple of years before (Grant 1916), and the influence of eugenic ideas impregnates many psychiatric discussions. Two of the authors of the 1918 classification are renowned eugenics promoters. Thomas W. Salmon is the medical director of the NCMH, an expert in the psychiatric evaluations on immigrants in Ellis Island, and a key player in the discussions around immigration policies (Salmon 1913). Horatio M. Pollock, a statistician and a precursor in the development of psychiatric epidemiology, draws on the data he collected at the New York State Hospital in order to inform current eugenics discussions around the most effective measures to prevent the spreading of mental illness (see Pollock 1921). Both authors share the same concern for the huge social cost of mental diseases and mental deficiency. They are both opposed to compulsory sterilization, but they wish to promote a broad range of other eugenic measures: from education to segregation, immigration restriction and marriage laws.

In Canada, similar concerns at the intersection of psychiatric nosology and statistics, hereditary considerations and the immigration issue arose during the same period. The Canadian equivalent of the NCMH, the Canadian National Committee for Mental Hygiene (CNCMH), was founded in 1918 by Clarence Hincks and Clifford W. Beers. Hincks’ mentor, Charles Kirk Clarke (1857-1924) – often considered the father of Canadian psychiatry – put a strong emphasis on the “degenerate character” of the immigrant population and was a strident proponent for radical eugenic measures. In the Foreword of William G. Smith’s A Study in Canadian Immigration, Clarke deplored with gravity that: “Why the United States attracted the many, and often the best, while we had to be content with the few, and frequently the worst, is easily to understood by those who had the courage to unearth the facts and recognize them as fact rather than fiction” (Smith 1920, 7-8). He furthermore deplored that there was no “port of entry similar to that of Ellis Island” at Quebec, where a close psychiatric examination of each new immigrant could be done.

Conclusion
The 1918 Statistical Manual reflects the general attitude of North American institutional psychiatry towards eugenics. Between 1907 and 1940, 18,552 mentally patients have been sterilized in the United States without the NCMH and the AMPA (transformed into the APA – American Psychiatric Association – in 1921) officially opposing this measure (Grob 1983, 173). In Canada, the involvement of the CNCMH in the establishment of sterilization laws was even more direct and proactive.

From the point of view of eugenicist promoters, however, it should be noted that psychiatric nosology has never been thought of as representing a central key issue. Psychiatric classifications were often considered not enough scientifically grounded and also too restrictive. The project to establish a truly “eugenical classification of individuals”, as defended for example by Harry H. Laughlin in his “Model Sterilization Law”, was much more inclusive, with the feeble-minded and the insane representing only two classes out of the ten proposed broad classes (e.g. paupers, inebriates, criminals…). Furthermore, the rationale and methodology for such a classification were sought in biology (Charles Davenport) and in psychology (E.L. Thorndike, R.M. Yerkes and Henry H. Goddard) through psychometric testing, rather than in classical psychiatric knowledge imported from old Europe.

In the 1930s, US psychiatric institutions sought already to distance themselves from the eugenics movement. The publication in 1933 of the first official edition of the Standard Classified Nomenclature of Disease, which included a section on Diseases of the Psychobiologic Unit, represents a turning point towards a more medical, positivist and optimistic psychiatric clinical practice. From then on, mental illness was commonly said to be just like any other illness. The end of WWII would mark both the end of the eugenics movement and the beginning of a new era of clinical standardization in the US, culminating in the advent of the first edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-I 1952). In Canada, despite eclectic diagnostic practices, the influence of the American psychiatric nosology, the DSM system, grew progressively during the following decades.

-Steeves Demazeux

• American Medico-Psychological Association, and National Committee for Mental Hygiene, 1918. Statistical Manual for the Use of Institutions for the Insane. New York: NCMH.

• American Psychiatric Association, 1952. Diagnostic and Statistical Manual of Mental Disorders (DSM-I). Washington DC: American Psychiatric Association.

• Berrios, German E., 1999, “Classifications in psychiatry: a conceptual history”, Australian and New Zealand Journal of Psychiatry 33(2):145-160.

• Davenport, Charles, 1912, “The Trait Book”, Eugenics Record Office Bulletin No.6.

• Demazeux Steeves, 2014, “Psychiatric epidemiology, or the story of a divided discipline”. International Journal of Epidemiology, 43(1):i53-i66.

• Dowbiggin, Ian Robert, 1991, Inheriting Madness: Professionalization and psychiatric knowledge in nineteenth-century France. Berkeley: Univ of California Press.

• Dowbiggin, Ian Robert, 1997, Keeping America sane: psychiatry and eugenics in the United States and Canada, 1880-1940. Ithaca, NY: Cornell University Press.

• Foucault, Michel, 1988. Madness and civilization: A history of insanity in the age of reason. New York: Random House LLC.

• Goldstein, Jan E, 1987. Console and classify: The French psychiatric profession in the nineteenth century. Cambridge: Cambridge University Press.

• Grant, Madison, 1916. The Passing of the Great Race: The Racial Basis of European history. New York: Charles Scribner's Sons.

• Grob, Gerald N., 1983, Mental illness and American society, 1875-1940. Princeton: Princeton University Press.

• Pollock Horatio M., 1921, “Eugenics as a Factor in the Prevention of Mental Disease”, Mental Hygiene, 5(4):807-312.

• Salmon Thomas W., 1913 “Immigration and the mixture of races in relation to the mental health of the nation”. In: White WA, Jellife SE (eds). Modern Treatment of Nervous and Mental Diseases. Philadelphia, PA: Lea and Febiger.

• Reports of the Immigration Commission, 1911, Dictionary of Races and Peoples. Washington: Washington Government Printing Office.

• Smith William G., 1920, A Study In Canadian Immigration. Toronto: The Ryerson Press.