Yin and yang and yang are bound together as parts of a mutual whole (for example, there cannot be the bottom of the foot without the top). A way to illustrate this idea is to postulate the notion of a race with only men or only women; this race would disappear in a single generation. Yet, men and women together create new generations that allow the race they mutually create (and mutually come from) to survive. The interaction of the two gives birth to things, like manhood. Yin and yang transform each other: like an undertow in the ocean, every advance is complemented
Zhou Dunyi credited in Taoism as the first philosopher to popularize the concept of the taijitu or "yin-yang symbol". Born in 1017 in Yingdao County, Daozhou prefecture, in present-day Yongzhou, southern Hunan, Zhou was originally named Zhou Dunshi. Raised by a scholar-official family, he was changed his name in 1063 to avoid a character in the personal name of the new Emperor Yingzong. His father died when he was fourteen and he was taken in by his uncle Zheng Xiang. He received his first posting in government through his uncle. Although very active in his civil service career, he never did achieve