Yang and Yin (or Yen)

are terms used in Chinese philosophy to indicate the two phases under which the ultimate principle of the universe displays itself in the phenomenal world. They were generated by Tai-ki, or the supreme principle — Yang being a perfect, subtle, celestial, luminous nature; Yin being matter, imperfect, crude, earthly, obscure. From this duality of opposite essences, called the two Ke, all created existences have sprung. Gardner (Faiths of the World, s.v.) quotes from Hardwick as follows: "According to the different proportions in which Yang and Yin are blended is the character of every created existence. Everything is Yang and Yin together. For the highest actual manifestation in which Yang preponderates we look to heaven itself, which is, accordingly, to be esteemed the aptest image cognizable by the senses of the ultimate and all-embracing principle. Earth is, on the contrary, the highest form of Yin. The same duality, where one or other of the factors operated, either for the purpose of transforming or uniting, issued in the first production of the innate essences, which constitute the five elements of water, fire, wood, metal, and earth. A transcendental union and coagulation now takes place of the ultimate principle, the two essences, and the five elements. The positive essence becomes the masculine power, the negative essence the feminine poweri conceived in which character the former constitutes the heavenly mode, or principle; the latter the earthly mode, or principle. By a mutual influencing, the two produce all things in the visible, palpable world, and the double work of evolution and dissolution goes on without end — Yang evincing its peculiar force in every kind of progress, Yin in every kind of retrogression; Yang determining commencement, Yin completion; Yang predominant in spring and summer, and the author of all movement and activity; Yin more visible in the autumn and the winter, passive, drooping, and inert." The same idea pervades their notions of rational as well as irrational beings. In the ethical system of the Chinese, evil is Yin of the moral world, and good is Yang. SEE CHINA.