Originating in Chinese philosophy, yin and yang, yinyang or yin-yang is the concept of opposite cosmic principles or forces that interact, interconnect, support and perpetuate each other. Yin and yang can be thought of as complementary and, at the same time, opposing. Together they form a dynamic system in which the whole is greater than the interdependent components, and both parts are essential for the cohesion of the whole.
― Yin and yang Wikipedia page