In ancient Chinese philosophy yin and yang is a concept of dualism, of how opposite or contradictory forces may actually be complimentary, interconnected and interdependent in the natural world. This is also true in the musical world. Music without shades of light and dark, loudness and softness, adagio and allegro (tempos), major and minor keys, and other dynamisms would be so boring. Music on the whole, could not exist without the contrasts in its aural landscape.