Yin-Yang: "Two polar energies that, by their fluctuation and interaction, are the cause of the universe. Yin and Yang are manifestations of the supreme ultimate, their concrete manifestations being Earth and Heaven.

From the union between yin and yang arise the five elements.

This manifestation of all phenomena is seen as a cyclic process, an endless coming into being and passing, a transformation of two opposites.

The underlying shared characteristic of yin and yang therefore consists in giving rise to this continuous change.

Originally the word yin designated the northern slope of a mountain, i.e., the side facing away from the sun- and was further associated with cold, turgid water and a cloud- covered sky.

Yang denoted the mountain slope facing the sun and was associated with brightness and warmth."  Yin and yang became representative of all polar relationships. Yin became "the feminine, the passive, the receptive, the dark, the soft. Symbols of yin are the moon, water, clouds, the tiger, the turtle, the color black, the north, and all even numbers. Yang corresponds to what is masculine, active, creative, bright, and hard. Symbols of yang are the sun, fire, the dragon, the color red, the south, mercury, and all odd numbers.

The well-known yin-yang symbol (the black and white circle) stands for the universe composed of yin and yang, which form a whole only in combination. The two spots in the symbol indicate that each of the two energies at the highest stage of realization already contain the seeds of the feminine and the masculine and are about to transform into their polar opposites.  " As for Chinese medicine, the body is healthy only when yin and yang hold each other in balance.

Too much yang causes heightened organic activity; too much yin, an inadequate functioning of the organs."