The Four Main Trigrams
The World Upside Down: Essays on Taoist Internal Alchemy, by Isabelle Robinet, page 66
Two trigrams are at the origin of all others, their father and mother. They are Qian ☰, which is related to Heaven and is made of three Yang solid lines, symbolizing pure Yang; and Kun ☷, which is related to the Earth and is made of three broken lines, symbolizing pure Yin. Qian and Kun joined and gave birth to the other trigrams, two of which are especially important for the alchemist: Kan ☵ and Li ☲. The inner line of Kan (a Yang line enclosed between two Yin lines) and the inner line of Li (a Yin line enclosed within two Yang lines) are True Yang and True Yin, respectively. Their multiple meanings and functions cannot be fully described here. Let it suffice to say that they represent the trace of the father and the mother and of their union; and that they express above all a fundamental principle of interdependence: there is no Yin without Yang, and vice versa, or there would be sterility.
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