perhaps the best-known Taoist alchemist of China, who tried to combine Confucian ethics with the occult doctrines of Taoism.

In his youth he received a Confucian education, but later he grew interested in the Taoist cult of physical immortality (hsien). His monumental work, Pao-p'u-tzu (“He Who Holds to Simplicity”), is divided into two parts. The first part, “The 20 Inner Chapters,” discusses Ko's alchemical studies. Ko gives a recipe for an elixir called gold cinnabar and recommends sexual hygiene, special diets, and breathing and meditation exercises. He even prescribes a method for walking on water and for raising the dead. The second part of the book, “The 50 Outer Chapters,” shows Ko as a Confucianist who stresses the importance of ethical principles for the regulation of proper human relations and who severely criticizes the hedonism that characterized the Taoist individualists of his day. A partial English translation of Ko's writings appeared in 1967 in James R. Ware's Alchemy, Medicine, and Religion in China of A.D. 320, The Nei P'ien of Ko Hung.