孔子所說的「鄭聲淫」歷來有三種主要的解釋：一是鄭國的詩歌（特指《詩經‧鄭風》）多描寫男女之情，是淫邪的；一是鄭國的音樂內容是淫邪的；一是鄭國的音樂是淫過的。這些解釋影響到孔子和《詩經》關係的認知，也影響到「詩序」是否傳自孔子的爭議。本文透過文獻的分析與音樂問題的解說，認為「鄭聲」是鄭國的地方音樂，也是俗樂的一個代表，其音樂形式表現得較為靡麗多變，不似雅樂的樸質莊嚴；並且進一步論證俗樂經過採集，並使之雅化而作為雅樂的一種，相對地，雅樂亦可以經過繁化而成為俗樂，二者有互相因襲沿變的關係，有相當的同質性，或說是一種音樂的兩般面貌；其中俗樂更加能迎合當時人的喜好，然而它似是而非的性質適足以淆亂時人對雅樂的認知，甚至有取而代之的傾向，所以孔子才會「惡鄭聲之亂雅樂」。

“Zheng sheng yin”─ as called by Confucius has ─ three leading explanations as follows: First of all, the poem (especially referring to the part in the Shijing) of Zheng country usually describes the obscene relationship between men and women. Secondly, the musical substance is indecent. Third, in terms of musical style, it exceeds many rules. The above affects the relation between Confucius and Shijing. This paper argues that the third explanation is much more correct according to the analysis of documentations and music. “Zheng sheng”, as the local music of Zheng country and a popular music, does not present simple and solemn appearance like the classical music but more garish and changeful. Further-more, this paper expounds and proves that popular music had been collected and classicized as a sort of classical music, while the classical music could also be complexed to be popular music: thus, the two shared certain similarity in very different appearance. The popular music is more receptable so that its status overrides that of the classical music; nevertheless, the popular no moral teaching, as much as the classical music, that is why Confucius disgusted “Zheng sheng” extraordinarily.