Religion and philosophical tradition originating in China, generally emphasizing individual freedom and spontaneity, laissez-faire government and social primitivism, techniques of self-transformation, mystical experience, and individual and government ethical responsibility. It is founded on the texts of the Tao-te Ching, Chuang-tzu, and Lieh-tzu. Later, the tradition diverged, resulting in strictly philosophical Taoism on the one hand, and religious Taoism on the other. The governing principle of the latter is the struggle to reach a state of 'immortality' through a strict regimen of dietary restrictions, breath control, meditation and visualization of the gods that inhabit the body, sexual control and discipline, the practice of theoretical internal alchemy (nei-tan) used to energize the Yin and Yang forces within the body, and the use of magic talismans. Successful devotees were known as hsien (Immortals).