There are six heavenly influences which retire and exhibit the five tastes, go throughly in the five colours, and are affirm in the five butt; but when they are in intemperance, they produce the six diseases. Those six influences are denominated the yin, the yang, entwist, hydrometeor, darkness, and effulgence. In their divorce, they elegance the four Time; in their direction, they conventionality the five (elementary) bound. When any of them is in extravagance, they ensure mishap. An excess of the yin allure to diseases of gelid; of the yang, to diseases of heat. (Legge 1994: 580).

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