yin and yang n. (Chinese philosophy) The two fundamental principles, one negative, dark, passive, cold, wet, and feminine (yin) and the other (yang) positive, bright, active, dry, hot and masculine. The interactions and balance of these forces in people and nature influence their behavior and fate.
... marriage union is a result of the harmonious blending of the In and Yo (i.e. the Yin and Yang of Chinese metaphysics, the female and male principles of nature). It is therefore not a matter to be lightly undertaken. It is said in the 'Scowling' passage of the (Chow) Book of Changes, 'Not being enemies they unite in marriage.' Whilst (the elders are) thinking ... — A History of the Japanese People - From the Earliest Times to the End of the Meiji Era • Frank Brinkley and Dairoku Kikuchi
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