Chang Tsai (1020–1077), Chinese philosopher, a major Neo-Confucian figure whose Hsi-ming (‘Western Inscription’) provided much of the metaphysical basis for Neo-Confucian ethics. It argues that the cosmos arose from a single source, the t’ai chi (Supreme Ultimate), as undifferentiated ch’i (ether) took shape out of an inchoate, primordial state, t’ai-hsü (the supremely tenuous). Thus the universe is fundamentally one. The sage ‘realizes his oneness with the universe’ but, appreciating his particular place and role in the greater scheme, expresses his love for it in a graded fashion. Impure endowments of ch’i prevent most people from seeing the true nature of the world. They act ‘selfishly’ but through ritual practice and learning can overcome this and achieve sagehood. P.J.I.