中國古代「原生性」的文學史觀，其中之一是「代變文學史觀」。「代變」一詞用在文學史觀，其義有二：一是用以描述二種以上形構差異的文學「體製」前後「更替」變動的現象；二是用以描述同一樣態性的文學「體式」，卻依「朝代」或「世代」的時序，因不同處境而更易變化的現象。「體製」與「體式」總合為「文體」。因此，「文學代變」其實就是「文體代變」，一部文學史就是「文體變遷史」。中國古代文學史上，關於「文體代變」，究竟什麼在「變」？「變」出於什麼原因、條件？「變」有什麼規律？歷代變遷的諸多文體各有什麼文學價值？中國古代文人對這些問題的回答所秉持的特定觀念，就是「代變文學史觀」。
      這一「代變文學史觀」，古代文人的論述非常紛雜。中文學界至今還未有學者能對這一文學史觀，經由各種文本的詮釋而統合出完整的觀念。本論文廣集諸多重要的文本，經由精密的文本分析詮釋，有效的回答：究竟什麼在「變」？「變」出於什麼原因、條件？「變」有什麼規律？歷代變遷的諸多文體各有什麼文學價值？而後綜合重構這一「代變文學史觀」系統性的「詮釋模型」，可資應用到《中國古代文學史》這一類著作的書寫。

      One of the ancient Chinese “original” perspectives of literary historiography is the “genre-shifting by era”. The term “genre-shifting by era” of literary historiography connotes two meanings. First, it describes the “alternative” changes of literary “styles” of more than two kinds of literary construction. It secondly describes the transformation of a single literary “style” that changes in diff erent situations according
to the chronological order of “dynasty” or “era”. The term “genre” integrates from the two terms: “style” and “forms”. Therefore, the “literature shifting by era” is actually the “genre-shifting by era”. Literary history is the “history of literature transition”. What exactly is “changing” in Chinese ancient literary history concerning “genre-shifting by era”. What are the causes and conditions that induce these “changes”? What are the regularities of these “changes”? What are the literary values in the changed genres throughout history? The underlying specific perspectives of the answers to these questions proposed by the ancient Chinese literati represent the “literary historiography on genre shifting by era”.

      The arguments on the “literary historiography on genre-shifting by era” by the ancient literati are extremely diversifi ed. To date, scholars of Chinese literature have not yet proposed a complete concept from interpretations of diff erent kinds of texts. By intricate text analyses and interpretations, this article assembles many critical texts and answers the following questions: What exactly is “changing” in Chinese
ancient literary history concerning “genre-shifting by era”. What are the causes and conditions that induce these “changes”? What are the regularities of these “changes”? What are the literary values in the changed genres throughout history? Subsequently, the systematically constructed ‘transformational literary historiography’ and its interpretive model can be applied to writing works such as ‘A History of Ancient Chinese Literature’.