《礼记·乐记》
所以，这样的乐，是审定一个基调以定调和之音，再配上各种乐器表现其节奏，使节奏合成为乐章，就可以用来使父子、君臣各安其位，和谐相处，使普天之下的百姓亲附。这就是先王制乐的原则。
故乐者审一以定和，比物以饰节；节奏合以成文。所以合和父子君臣，附亲万民也，是先王立乐之方也。
Therefore, such music is to determine a keynote to determine the harmonious sound, and then match it with various instruments to express its rhythm, so that the rhythm can be combined into a movement, which can be used to make the father and son, the monarch and his ministers each in their place, and live in harmony. Make the people of the world intimate. This is the principle of the ancient kings' music.