The most significant part of Chinese philosophy, is the 'all in one' belief. The earth, the celestial objects and human are all ONE system. It is important to notice that in this ONE system, there is no superior part. Each and any in the system has the ability to disturb it and cause it to deviate from the perfect harmony.
This 'lack of superior' philosophy was originated in the pre-class society. The scares of food and other living materials required every member of the society to be extremely considerate to other's needs. There was not even the co-existence of the Yin and Yang. It was simply co-existence because nobody could exist alone. There was no conflicting interest.
The co-existence and co-dependent of the opposite was originated around the 2600-2100 B.C. The growing awareness in the difference of the earth below and the celestial objects above, the men and women, the sun and the moon, the day and the night started to appear on the philosophical level. The two sides in one is not simply head and tail of one coin. It is even more than I am inside you while you are inside me type co-existence. Yin is originated from Yang and Yang is originated from Yin. They encircled and embrace each other. The constant moving balance is the ideal image of harmony.