Sometimes I worry about humanity.
In Japan, you are what your blood type is
In the year just ended, four of Japan’s top 10 best-sellers were about how blood type determines personality, according to Japan’s largest book distributor, Tohan Co. The books’ publisher, Bungeisha, says the series – one each for types B, O, A, and AB – has combined sales of well over 5 million copies.
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As defined by the books, type As are sensitive perfectionists but overanxious; Type Bs are cheerful but eccentric and selfish; Os are curious, generous but stubborn; and ABs are arty but mysterious and unpredictable.All that may sound like a horoscope, but the public doesn’t seem to care.
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Matchmaking agencies provide blood-type compatibility tests, and some companies make decisions about assignments based on employees’ blood types.Children at some kindergartens are divided up by blood type, and the women’s softball team that won gold at the Beijing Olympics used the theory to customize each player’s training.
Not all see the craze as harmless fun, and the Japanese now have a term, “bura-hara,” meaning blood-type harassment.
And, despite repeated warnings, many employers continue to ask blood types at job interviews, said Junichi Wadayama, an official at the Health, Welfare and Labor Ministry.
http://www.physorg.com/news152723712.html
Wow. All of those blood type personalities are so totally me.
Tiny Frog 
[…] A, B und AB. Ganz Recht, Blutgruppen-Horoskope stehen in Japan ganz hoch im Kurs. Die Details hat Tiny Frog: “In Japan, you are what your blood type is” « Calvin, der Skeptiker Dieser Eintrag wurde von Benjamin B. geschrieben, am Monday, […]
I had heard of the blood-type personality thing, but I didn’t know it was so prevelant there.
Yep, it’s prevalent here in Japan, though I don’t know how many people really take it seriously. All started some time back – 20 years or so? – when someone introduced the idea in a book.
I would love to see a proper empirical debunking of the notion, if anyone knows of one. (Or heck, a proper empirical *proof* of it, if it should – to my surprise! – turn out to have merit!)
By the way, I’m an O – but, like any goofy astrological personality matrix, I can see myself in *any* of the broadly drawn descriptions. Meh.
I’m an A+, which explains why I always did well in school.
Yeah, I don’t know much about efforts to debunk it. I suppose it would be similar to efforts to debunk astrology. Even without a “proper” debunking, from the standpoint of reason, it just seems absurd to claim that the small amino-acid chains on red-blood cells would play such a large role (or any role at all) in forming a person’s personality. Even if that were true, one would expect that all different kinds of amino-acid chains hanging off cells (there are probably millions of these) would affect personality – which would mean the blood-based personality effects would be swamped-out by other amino-acid chains. In other words, they have to believe that the short amino-acid chains associated with blood-types have huge effects, while claiming that the millions of short amino-acid chains everywhere else on cells plays no role in personality formation.
Well, in this case as in many, burden of proof is on the maker of the claim. So if the claimants can’t show valid scientific support for the idea, then it’s effectively debunked.
And can they do so? Truth to tell, I don’t know; I never looked into the support for the claim. It just sounded too silly, and not particularly a topic of interest to me anyway. Heck, who knows, there *could* be truth to it. I can only say that, for reasons such as those you mention, it sure *sounds* goofy!