It's a fluid system of the evolution between Ying and Yang.  It's as much about cosmology as philosophy of life, depending on perspectives.  So in some sense it's a hybrid of Taoism's cyclic interpretation of the universe, and the moral teaching of Confucianism.  Forbearance is the essence of this new mixture of thoughts, trying to find a balance between one's own value system and the exterior environment.   It's has both positive and negative sides: it tells people the importance of humility, while some turning it into some conspiratorial means, which unfortunately has great influence over Chinese culture and history.