The Music of the State of Zheng
This refers to popular folk music in history, as opposed to formal ceremonial music. The term, originally “the music of Zheng and Wei,” referred to music from the states of Zheng and Wei during the Spring and Autumn and the Warring States periods. Unlike stately, grand and highly structured classical music, the music of Zheng featured free-flowing melodies and a wealth of variations, with lyrics that often spoke of the love between men and women. Confucius felt that works of this sort gave free rein to personal emotions and lacked purity in ways of thinking, that they were not conducive to educating people through etiquette and music, and should therefore not be permitted. Many scholars subsequently used “the music of Zheng” to refer to lowbrow arts, but others considered these tunes to be folk songs which were a form of popular culture, a source of artistic creation and a complement to highbrow arts.
Cast aside the music of Zheng, and keep your distance from smooth-talking petty men. The music of Zheng is seductive, and smooth-talking petty men are dangerous. (The Analects)
Classical music from the era of Yu and Shun is hard to grasp, whereas the crass and seductive music (of Zheng) can easily become popular. Do you think Jizha only wanted to listen to the music of the State of Lu? He wanted to understand, through music, the decline of rites and etiquette. (Liu Xie: The Literary Mind and the Carving of Dragons)