hsien
Some of the earliest texts of Chinese Taoism refer to immortal spiritual masters, the hsien. Their miraculous acts, such as riding on clouds and holding power over nature, served to illustrate Taoist ideals. While these references seem to have been allegorical, later texts speak of hsien much more literally. By the fourth century C.E., the promise of hsien had given rise to a practical alchemy. Adepts practiced dietary restrictions, breath control, and other esoteric techniques, all in pursuit of the immortality of the masters.