Longing for a reason to discriminate other people, Japan simply invents one.

[DetlefK]

http://www.thedailybeast.com/articles/2017/05/29/un-true-blood-japans-weird-taste-for-discrimination-against-type-bs

At least since the 1920s, many Japanese have held a superstitious belief that there is a serious correlation between blood type and personality. Type As, (like Jake Adelstein), are supposed to be considerate, hard-working, and pay great attention to details. Type Os are good baseball players, happy-go-lucky, easy-going, and amiable. However, in recent years, according to a prominent critic of this pseudo-science, there is discrimination against certain blood-types—especially “the opinionated and extremely curious” Type Bs.

The Japanese term for this is “blood harassment” or “burahara” when abbreviated.

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“But even in a country like Japan where roughly 98 percent of the population is the same ethnicity, people still find a way to discriminate and group people into convenient molds.”

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Masao Ohmura, personality psychologist at Nihon University, suggested in a Japan Times article, that because the Japanese are genetically quite a homogeneous people, grouping by blood was a way of achieving diversity—if only the illusion of diversity.

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Negative stereotyping credits the B types as selfish, and ABs as eccentric and unpredictable.

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Japan has long been a country where the population is 98-99 percent Japanese, and discrimination against identifiable outsiders remains prevalent. Third or fourth generation Korean-Japanese who often do not speak Korean and are indistinguishable from Japanese people in appearance often are treated with disdain. There’s even discrimination against the burakumin, the former outcast clan of Japan who were once butchers and leather workers.

Blood type discrimination is an extension of these attitudes and the government is discouraging it officially. But, ironically, Japan’s governments have done little as yet to discourage more blatant forms of racism. If only there were more aggressive and courageous B-types or open-minded internationally inclined AB types in the government, perhaps we’d see some change for the better.





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For example, if you look at old japanese video-games from the 1980s and 1990s, sometimes the character-description also mentions the blood-type. To the Non-Japanese this is just odd, but to a japanese player it tells him what kind of personality that fictional character has.