Perhaps the chief interest in its study lies in the fact that we may see today the persistence of views about disease similar to those which prevailed in ancient Egypt and Babylonia.

The Chinese believe in a universal animism, all parts being animated by gods and spectres, and devils swarm everywhere in numbers incalculable.

The universe was spontaneously created by the operation of its Tao, "composed of two souls, the Yang and the Yin; the Yang represents light, warmth, production, and life, as also the celestial sphere from which all those blessings emanate; the Yin is darkness, cold, death, and the earth, which, unless animated by the Yang or heaven, is dark, cold, dead.

The Yang and the Yin are divided into an infinite number of spirits respectively good and bad, called shen and kwei; every man and every living being contains a shen and a kwei, infused at birth, and departing at death, to return to the Yang and the Yin.

Thus man with his dualistic soul is a microcosmos, born from the Macrocosmos spontaneously.