(“inner cultivation”), an early Chinese Taoist system aimed at purifying the practitioner's “vital force” (ch'i (qi)) and enabling him to attain awareness of true reality as encompassed in the Tao. In hsin-shu the purification of ch'i meant cleansing the mind and heart of thoughts and emotions; only when an individual had reached a state beyond conscious desires, fears, and ideas was he able to receive the spiritual power of the Tao. Control of breath seems to have been the main technique for achieving the desired state.

For the hsin-shu theorists, spiritual awareness was not an end in itself; their ideal figure was the sage-activist who exerted a powerful and positive influence on the governing of the nation. Health and prolonged life were also said to result from practicing hsin-shu. Many non-Taoists, including possibly the Confucian sage Mencius, were influenced by hsin-shu theory during the late 4th and early 3rd centuries BC. Its two major texts, included in the book known as the Kuan-tzu, date from this period.