The Chinese, like the ancient Egyptians, were deeply concerned with guaranteeing the survival of the individual; the person’s being, after physical death. Their ideas were based on the ancient Chinese conception of the polarity of negative and positive, dark and light, yin and yang; the two essential principles in the cosmos, the eternal universal balance. But what does that have to do with vampires? I’ll explain soon enough, don’t you worry my sweets.
According to the Chinese, just like the universe consists of yin and yang, a balance of negative and positive, the same goes for people. The human personality consists of light and dark “souls.” There is a light soul, the Hun (also known as animus) and the dark soul, P’o (also known as anima), which are welded together during life but are separated at death. The hun soul is the superior of the two; it partakes in the finest, the best and good qualities of a person. The p’o soul on the other hand is inferior, it is the dark and evil part of a being, totally negative.
Now that that is explained we can get to the vampire point. In Chinese vampire lore, the p’o plays an important part in the creation of the undead. Should any part of a corpse remain intact or undestroyed, the p’o might be able to use this part to pass forth from the tomb or grave, becoming a vampire and making that body or body part the base of its powers. The accidental exposure of whole body parts to the sun or the moon was a terrible move, as the p’o gained power from both and could be energized enough to go out and drink human blood, thus adding even more to its strength. So, while the hun goes on to the afterlife, the p’o can become an evil spirit or vampire.
Another ancient belief on an ancient subject.