Yin-Yang (pronounced yin-yan) are two opposite forces that exist in harmony, complement each other, and are dependent on each other. Yin is characterized as the negative force of darkness, coldness, and emptiness; yang as the positive force of light, warmth, and fullness. Yin-yang represents the two primal, opposite forces; hard and soft, masculine and feminine. The binary list is endless.

Both configurations are enclosed in a circle, which is indicative of the cyclical evolution of nature. The transmutation of two opposites is represented by the dark area blending into the white. Harmony between these opposite attributes is shown by the equality of the two areas. The white dot in the dark area and the dark dot in the white area of the double fish configuration show the interdependency of the two. During kung-fu’s evolution, the spiral configuration was adopted by the intellectuals and scholars, and the double fish configuration became synonymous with the commoners.