Isabelle Konuma

Isabelle Konuma, senior professor of Japanese studies at INALCO, recently published Eugénisme au Japon—Politiques et droit de 1868 à 1996 [Eugenics in Japan: Policies and law, 1868-1996] with INED Publications. She answered our questions about the premises of eugenics in Japan and the impact of the practice on the country’s demographics at the present time.

(Interview conducted in February 2025)

The term was translated into Japanese as yûsei early in the twentieth century to designate Galton’s thinking. We find the term in the national eugenics law of 1940, which was replaced in 1948 by a eugenic protection law; in 1996 it was withdrawn from Japanese law. Inspired by different eugenics models (British, German, American and others) and imperatives within the country at different times (colonialization policy, post-war demographic crisis and others), eugenics/yûsei refers to any procedure of selecting or identifying favorable or unfavorable reproductive behaviors according to values identified by the law, policies, and practices. Under the law of 1948, the scope of eugenics expanded considerably, encompassing not only genetic aspects but also living conditions (married couples’ child-bearing plans, mother’s availability during the child’s first years, hygienic follow-up during pregnancy and childhood, etc.).  This was done by way of numerous campaigns with social goals in which local communities were heavily involved, such as “the movement for a new life” (Shinseikatsu undô) and “the movement to prevent the birth of unhappy children” (Fukô na kodomo no umarenai undo)..

Despite being chronologically close, the national eugenics law of 1940 (Kokumin yûseihô) and the eugenic protection law of 1948 (Yûsei hogohô) did not have the same objectives and were enacted in different contexts. The law of 1940 reflected the thinking of the Japanese Racial Hygiene Society (Nihon minzoku eisei gakkai), which had been developing since the 1930s, and was heavily influenced by British, American, and German approaches. However, both the national context (the rise of science and curative medicine) and nationalist ideology (of the family-state and “paternal imperial blood,” combined with ancestor worship) prevented that law from extending as far as may have been wished. The law of 1948 was passed in a context of military defeat and “ethnic reconstruction” (comparable to what occurred during the interwar period in Germany), where if became vital to control demographics following the baby-boom (1947-1949) and the repatriation of colonists and military personnel once the colonies had been returned. In this context, it was deemed crucial to lower birth numbers in a controlled way and to rebuild a people of “quality”; the law was also needed to create a “state of culture” and to implement social measures. To understand the reproductive model founded on these two laws, it is essential to probe the rapprochement, not to say complementarity, between eugenics and fundamental rights, rights that had just been redefined and reaffirmed in the Constitution of 1946.

The book puts forward a new interpretation of “de-natality” in Japan. Falls in fertility are often explained in terms of girls’ schooling and women’s labor market integration, men’s difficulties finding stable employment, the importance of marriage before reproduction, or the model of sex-based domestic task sharing. But those studies do not always go so far as to question why such a model as eugenics—which dictates marital and reproductive behavior to generations of reproductive age—should exist. By recalling and focusing on the existence of a post-war eugenics regime that called not only for improving the population’s descendants in genetic terms but also improving children’s living conditions (conjugal model, interest in neo-Malthusianism, depenalization of abortion, “the myth of mother love,” etc.), this study aims to present a new reading of “de-natality” in Japan, the result of an actively undertaken policy to reduce births through eugenics methodology.