This is what Confucius said of the description of love between young men and
women in the poem entitled "Guan Ju" in "Ballads of Zhounan," The Book of
Songs. Later Confucian scholars regarded this as a basic requirement for poems
and other literary works to advocate impartiality, peace of mind, and harmony
between emotion and reason, making it a criterion for evaluating literary works.
Its connotation is in accord with zhongyong (the golden mean) of Confucianism.
In the more recent history, the connotation of the term has been continuously
renewed to keep pace with the times.