A common superstition in Japan is that blood type is an indicator of a person's personality; similar to the Western belief in the Signs of the Zodiac (the Zodiac custom is also popular in Japan).
This custom is said to have started when some doctors in Japan made a medical report stating that people with Type A Blood were generally mild-tempered and intellectual, while people with Type B Blood were just the opposite. Today in Japan, blood type is popularly used as a personality-type indicator. Even though it hasn't been proven to have any scientific basis, many Japanese people believe in these distinctions to one degree or another.
Furukawa Takeji (1891-1940) proposed the theory on the relation between blood types and temperament. During the late Taisho -- early Showa period (1920s).
There are three facts that were found especially interesting and informative.
(1) Furukawa majored in experimental education at university, and upon his employment at a women's high school, he worked in its administration office. He came to believe there that temperamental differences of applicants were responsible for the failure of predicting school performance from results of entrance examination.
(2) He thought that human temperament was so simple that a theory needed to consider only two temperament types.
(3) He was from a family of many doctors, and was familiar with blood type, which was the newest physiological discovery of the day.
Type A
Speaking broadly, it is said that people with Type A Blood are calm, composed, and very level-headed and serious. They have a firm character, and are reliable and trustworthy (and hardheaded). They think things over and make plans deliberately, and they plug away at things steadily and assiduously. They try to make themselves more like their own ideal of what they should be. A Types may look aloof or distant to others. They try to suppress their own emotions, and because they have continual practice in doing this, this makes them appear strong. But, actually, they have a fragile, nervous side, as well. They tend to be hard on people who are not of the same type, and so they consequently tend to be surrounded with people of the same temperament.
Type B
People with Type B Blood are curious about and interested in everything. That's may be good, but they also tend to have too many interests and hobbies, and they tend to get all excited about something suddenly and then later drop it again just as quickly. But they do manage to know which of their many interests or loved ones are the ones that are really important, the ones they should hold on to. B Types tend to excel in things rather than just be average. But they tend to be so involved in their own world or become so carried away with something that they neglect other things. They have the image of being bright and cheerful, full of energy and enthusiasm, but some people think that they are really quite different on the inside. And it can also be said about them that they don't really want to have much real contact with others.
Type O
Type O Blood people are said to set the mood for a group and to take on the role of creating harmony among its members. Their image is one of taking it easy, of being peaceful and carefree. They are also thought to be big-hearted and benevolent, and they tend to spend money on others generously. O Types are generally "loved by all." But, they also, surprisingly, have a stubborn and strong-willed side, as well, and tend to secretly have their own opinions on things. On the other hand, they have the flexible, adaptable side of readily accepting new things. They are easily influenced by other people or by what they see on TV. They seem to appear level-headed and trustworthy, but they often slip and make big blunders inadvertently. But that is also the point that makes O Types lovable.
Type AB
People with Type AB Blood are said to have a delicate sensitivity. They are considerate of other people's feelings and deal with them with care and caution. On the other hand, though, they are strict with themselves and those close to them. They, therefore, seem to have two personalities: one for those "outside," and another for people on the "inside." They often become sentimental, and they tend to think too deeply about things. AB Types have a lot of friends, but they need time to be alone and think things through, as well.
Blood Type A is the most common Japanese blood type. In America, Blood Type O is by far the most prevalent. In Japan, schools carry out thorough physical exams, and so the majority of Japanese people find out their own blood types from the results of these exams. Many Japanese are amazed to learn that a large number of Americans don't know their own blood types. "What's your blood type?" is a question heard much more frequently in Japan than, say, "What's your zodiac sign?" is heard in America. It is sometimes even used in casual self-introductions in informal situations.
Hence this is why you will see in many Anime and Manga listings and information and talked about blood types. This shows how blood type is considered an important enough characteristic in Japan.
I had to put this in because I couldn't figure out why every Asian actor I reviewed or looked up had their blood type posted. At the time, I was like "who gives a flying ****". Evidently the Asain culture do. So I've been doing a little research and comparing it to the Western culture of the zodiac. I'm a Leo. And I'm a total Leo through and through...even the physical traits are soooooo ME.
Well, if you take my blood type (O+) and add my Lioness traits and put them together...well, you get a perpetual bitch. LOL! I'm sure once Bobby reads this he'll be in total agreement. LOL!
But then if you add the Chinese zodiac sign of the Boar (yeah, I was born the year of the pig...stop laughing!), it evens me out and makes me an alright normal person. *whew* I was getting scared there a bit.
