An article by Mari Yamaguchi discusses how Japanese believe blood type determines personality. “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.”
Many Japanese believe so strongly about the relationship between blood type and personality there are cases where blood type has lead to discrimination and to a type of harassment referred to as “Bura-hara.”
While these claims are without scientific foundation and are what we refer to as pseudoscience, they are accepted by people who believe that certain facts, traits, or previous events basically determine who they are and define who they can be. This can be traced back to the “Nature-Nurture” debates in behavioral science. Are we born to be? Or de we learn to be? Watson and early behaviorist believed that we are shaped by our environment and that we can learn to be anything we want basically.
Behaviorists believe that under the proper conditions (contingencies) we can learn new behaviors and essentially be better at what we do and thus who we are. I have had students in my class with life long problem behaviors such as extreme nail biting. They felt since they have been that way all of their lives, that is how they will spend the remainder of their lives. In class after being taught the ABCs of behavior, they were able to quit the habit within the 4 month semester.
It is problematic when people buy into the misconception that we cannot change. This is probably why people cannot accept the fact that they too can reinvent themselves to be with in reason what they want to be. While I can’t change my blood type (O = generous but stubborn) I refuse to believe I can’t change : -)