Blood Types in Japanese Culture - History

History

The ABO blood group system is widely credited to have been founded by the Austrian scientist Karl Landsteiner, who discovered three different blood types in 1900. Ethnic studies showed different blood group distributions across the world (for example, in the 1900s, German people were sampled as having mostly types A and O blood, while Asians, Jews, and others were discovered to have a higher percentage of blood type B). This research was used by the Nazis to further ideas of supremacy over different races. These notions were debunked before Nazi Germany invoked race laws such as the Nuremberg Laws, where the wording "German blood" is figurative for Aryan lineage.

In 1926, Rin Hirano and Tomita Yashima published the article "Blood Type Biological Related" in the Medical Journal of Army. It was seen to be a non-statistical and unscientific report, motivated by racism.

In 1927, Takeji Furukawa, a professor at Tokyo Women's Teacher's School, published his paper "The Study of Temperament Through Blood Type" in the scholarly journal Psychological Research. The idea quickly took off with the Japanese public despite Furukawa's lack of credentials, and the militarist government of the time commissioned a study aimed at breeding ideal soldiers. The study used ten to twenty people for the investigation.

In another study, Furukawa compared the distribution of blood types among two different ethnic groups, the Formosans in Taiwan and the Ainu of Hokkaidō. His motivation for the study appears to have come from a political incident: After the Japanese occupation of Taiwan following Japan's invasion to China in 1895, the inhabitants tenaciously resisted their occupiers. Insurgencies in 1930 and in 1931 resulted in the deaths of hundreds of Japanese settlers.

The purpose of Furukawa's studies was to "penetrate the essence of the racial traits of the Taiwanese, who recently revolted and behaved so cruelly". Based on a finding that 41.2% of a Taiwanese sample had type O blood, Furukawa assumed that the Taiwanese rebelliousness was genetically determined. The reasoning was supported by the fact that among the Ainu, whose temperament was characterized as submissive, only 23.8% had type O. In conclusion, Furukawa suggested that the Japanese should increase intermarriage with the Taiwanese to reduce the number of Taiwanese with type O blood.

Interest in the theory faded in the 1930s as its unscientific basis became evident. It was revived in the 1970s with a book by Masahiko Nomi, a lawyer and broadcaster with no medical background. Nomi's work was largely uncontrolled and anecdotal, and the methodology of his conclusions was unclear. Because of this, he was heavily criticised by the Japanese psychological community, although his books remain popular. His son continued to promote the theory with a series of books, and by running the Institute of Blood Type Humanics.