It depends. If you mean personality, then dual personality is a body with two independent thinking systems. This explanation is very complicated and can be simply understood as two different people living in the same body. Multiple personalities, which can almost be understood as multiple people sharing a body and * * * sharing a body. This kind of personality is difficult to form, which is triggered by the national defense mechanism of the human body. Not much to say here. Talking too much will confuse you.