Ketsueki-gata

Otherwise known as prediction of character through blood types. Like the Astrological signs in the West AND like the Chinese Zodiac.

From what I've seen in America, people really don't pay much attention to their blood type, which I think is unfortunate because if you ever need a blood transfusion it takes time to test you for your blood type. In an emergency seconds can be really important.

I know I'm an O-... I know sucks right?!! But here are the blood types for humans(lets not worry about the + and - for right now); O, A, B, and AB.

  Chart from Google.
Okay, as you can see, the blood types are caused by the absence or presence of antigens on the surface of the red blood cell. You can only have one blood type present in your blood stream, if you are given the wrong blood type your body will reject it and that can potentially make you sick. This is why knowing your blood type and having a record of it in your medical records is essential.

Blood types are inherited from the parents, but a mother can often carry a child that has a different blood type.

The + and - signifies the RH system. The Rh system tells people that you either carry or do not carry an antigen, most commonly the D antigen. So RH+ means your blood DOES contain the D antigen and if your RH- it means you DON'T carry the D antigen. + types can receive both + and - blood types and - can only receive negative types.

O+ blood type's can only receive O+ and O- blood. O-'s can only receive O- blood(hence why is sucks to be an O-). A+'s can receive A+, A-, O+, and O- blood. A-'s can receive O- and A- blood. B+'s can receive B+, B-, O+, and O- blood. B-'s may receive O- and B- blood. AB+ can receive any blood type... so if your AB+ your super lucky! AB-'s can receive AB-, A-, B-, and O- blood. So because I'm an O- I'm a universal donor, but I can only receive type O- blood.

I will now note that Japan, as far as I know, doesn't recognize the RH factor in Ketsueki-gata. 

But on to the topic at hand: Ketsueki-gata...Like in Western Psychology, there are various personality types in Japan. There are differing variations on this such as Myers-Briggs personality types, in which there are 16 personality types. In the West, There are types A, B, C, and functional A personalities. A is aggressive, and they have a predisposition to get heart disease. B people are laid back and tend to be calm, most people tend to be considered B's. C's are introverted and have a predisposition to cancer. Functional A's can work through their aggression. (A/B Meyer Freidman and Ray Rosenman) (C Temoshok and Dreher) (Functional A (Hardy Personality) Suzanne Kobasa)

In Ketsueki-gata:

Type A: Positive traits: Creative, reasonable, responsible, reserved, patient, helpful.
Negative traits: tense, easily stressed, stubborn, meticulous, demanding.

Type B: Positive traits: Wild, adventurous, active, creative, passionate, strong, daring.
Negative traits: Irresponsible, unpredictable, careless, reckless, undependable, immature.

Type AB: Positive traits: Controlled, rational, social, 'split personality', spontaneous, collected.
Negative traits: Critical, 'split personality', indecisive, forgetful, hesitant, belittling.

Type O: Positive traits: Agreeable, sociable, optimistic, mild, compatible, calm, amendable,
Negative traits: Vain, rude, jealous, arrogant, abrupt, insensitive, awkward, aggressive.