Refers to people's spiritual aura. In ancient times, it was believed that the soul was Yang, which constituted human thinking and intelligence. The spirit is a rough and turbid Yin Qi, which constitutes the human sensory form. Harmony of soul (Yin and Yang) leads to human health. The dead soul (Yang Qi) belongs to the sky, the spirit is separated from the spirit (form), and the flesh and blood (Yin Qi) belongs to the earth. The soul is a yang god, and the soul is a yin god. Taoism has the saying of "three souls and seven spirits". Now science cannot prove whether the human soul can be detached or reincarnated as religion says, and whether the composition of the soul is correct.