阴阳 (Yin-Yang) is a foundational concept in Chinese philosophy and cosmology that illustrates how seemingly opposite or contrary forces are interconnected, interdependent, and complementary. It embodies the belief that all things in the universe consist of two opposing yet harmonious energies that continuously interact and balance each other. In this composition, I reflect the concept of 阴阳 through the interplay between a wind quartet and a string quartet. The wind quartet represents 阳 (Yang) through the use of the harmonic series. The string quartet represents 阴 (Yin) through the subharmonic series. Like 阴阳 itself, the two quartets are interconnected, interdependent, and complementary, their musical materials entwining and transforming to create a dynamic equilibrium. The interaction between them not only highlights their differences but also reveals their unity, reflecting the ever-present balance of Yin and Yang.