Tai-ji & Yin-yang
The ancient Chinese philosophy, that Yin and Yang are the two sides of black and white
“Yin” and “Yang” were often used instead of north and south by ancient chinese, it originated from the Central Plains during the Xia Dynasty (2070 BC – 1600 BC) , refering to the middle reaches of the Yellow River that is in the area north of the Tropic of Cancer, in which there will be no direct sun all year around, the sun will only shine from the south.
So for the mountains, the south side of the mountain can be illuminated by the sun, that is, the “Yang” is sunny, and the north cannot be shined which is “Yin”. So that “Yin” is the dark side that is not sunny, usually it means the south of the river and north of the mountain; “Yang” is the bright side of sunshine, usually it means north of the water and south of the mountain. However, because of the different direction of the mountains and rivers, so it may represent in the other way around. Some places and cities are named after the mountain and river, for example: Huai Yin City means the city on the south of Huai River
With the emergence of Zhou Yi , “Yin” and “Yang” expanded from the simple metaphor of dark and bright to the nature of all things, and then it has evolved into the cornerstone of the “Tao” theory.
This is what “Tao” contains that one Yin and one Yang refers to the two opposing and interconnected forces in everything in the world, and in such an unpredictable state that cannot be measured. Eventually it became the foundational doctrine of all mystic schools.
Yin and Yang are the two sides of black and white of Taiji, and Yin and Yang can produce Taiji. Taiji in Taoism generally refers to the most primitive state of order in the universe, it appears after the chaotic period (Wu Ji) of Yin and Yang, then formed the origin of everything (universe).
It is also an overview of the development of the world. The process that Taiji generates two complementary forces is how the heaven and earth was formed up.
Black and white in the Taiji diagram are the respective attributes of Yin and Yang. The “S” line represents the change of Yin and Yang and the balance between movements. Among them, white eyes in black and black eyes in white represent Yang in yin and Yin in Yang. and it means infinite separability in Yin and Yang metaphorically