It has been said above that the year BC 604 was, probably, that of Laozi’s birth. The year of his death is not recorded. Ssŭ-ma Chʽien , the first great Chinese historian, who died in about BC 85, commences his “Biographies” with a short account of Laozi . He tells us that the philosopher had been a curator of the Royal Library of Chou , and that, mourning over the decadence of the dynasty, he wished to withdraw from the world, and proceeded to the pass or defile of Hangu, 7 leading from China to the west. There he was recognised by the warden of the pass, Yin Hsi (often called Kuan Yin