What is the meaning of Yin and Yang two gas of the western zhou dynasty?

Week, according to the mandarin language "records, GuoWenGong advised king xuan of zhou held after the ceremony of cadastral field, there are" example shock Yang bi fears of hair, the hair "" distribution of Yin and Yang, seismic ray delay".Weeks, and reigned two yearsThe earthquakeFather, "Yang said:" Yang fu not out, Yin forced not evaporate, so there are earthquakes."

We can see from the transcript, in the western zhou dynasty, people started to use of Yin and Yang to explain astronomical geography phenomenon.

Book "Lao zi", said: "all things negative Yin can embrace Yang, air flushing thought and", refers to the Yin and Yang two gas.

Yin and Yang is considered to be forms the foundation of the universe, the world all things are available, Yin and Yang.Such as day for Yang, for Yin;To Yang, the month is Yin;For Yang, Yin is below;Left for Yang, right for Yin;Male to male, female for Yin...As the example, tianrui, "said:" the tao of heaven and earth, the Yin and Yang "is often the case with the ancient cosmology.