The Han-dynasty scholar Master Mao, in his preface to The Book of Songs, says: "Start from feelings; control them with morality," stressing that what comes first is true emotion from within, which is the motive power in life; the constraints of ritual and etiquette are meaningless without it.
毛詩序說：「發乎情，止乎禮義。」強調於先的是發自內心的真情，那是動力，然後才是禮義的約束。