本文主張古漢語出現句末的「云」並非過去學者所認定的語氣詞，而是終結語篇段落的言談標記。言談標記「云」從言說動詞虛化而來，其語法化路徑可描寫為：引語動詞＞引語標記＞言談標記。在此過程中，「云」從原本帶有 [＋說 ]和 [＋指示 ]兩個語義徵性，終至丟失了言說動作義，僅以相當於「這樣」的指示義標誌一個段落的結束。成熟的言談標記之例見於漢代，絕大多數出現於《史記》和《漢書》，可以說「云」的使用是史傳語體的特性。究其原因，大概是謂詞性代詞「云」的意義契合於史傳的記述性質之故。

This paper argues that the Classical Chinese sentence-final yun 云 is not a mere utterance particle as has been discussed. My study shows that the sentence-final yun 云 in fact serves to indicate the finality of discourse units and that yun 云 as a discourse marker is arguably descended from its full verb form meaning “to say.” In its course of grammaticalization, yun 云 first develops into a quotative verb, then a quotative marker, and finally a discourse marker. At first, both of yun’s 云 semantic features [+to say] and [+demonstrative] remain intact, but at the end of its grammaticalization path, yun 云 loses [+to say] and is only left with [+demonstrative]. This not only forms yun’s 云 new core meaning “this” but also renders yun 云 finality as a discourse marker. The usage of yun 云 as fully fledged discourse marker can be witnessed in texts in the Han dynasty, especially in The Classic of Poetry and The Book of Han. It can be said that the use of the discourse marker yun 云characterizes the historical narrative genre, for the meaning and the function of yun 云 as predicative pronominal accord well with the narrative nature of historical records.