明代復古派摹擬太甚的問題，不僅遭遇來自社群外部的挑戰，始終也是其內部有識之士深所焦慮。對於這種「創作實踐」的現象、流弊，他們是否透過「理論思維」層面的探索、建構加以救治？面對時下詩壇日漸增強對於摹擬流弊的攻擊力道，又是如何與時俱進，繼續堅守復古壁壘？本文認為，晚明許學夷在《詩源辯體》中的杜詩學論述，因其著述性格和歷史位置，提供了一個絕佳的觀察窗口。故本文首先梳理許學夷杜詩批評的主要內容，以奠定後續討論基礎；再進一步置入復古派前行詩學傳統脈絡，以凸顯許說之新異性和重要意義。研究成果顯示：許學夷對杜甫五古、歌行和律詩諸體的審美特色，進行了極精細的分類、描述和評價，實具重大意義。如杜甫五古「通變」，歌行「以興御意」，尤其是杜甫和盛唐諸家律詩「各自為勝」，諸說對復古派前行詩學傳統皆深具反叛意味，卻亦果能消弭摹擬流弊，繼續堅守古典詩歌美學理想。他的獨到見解，並為清初王漁洋詩說導夫先路。 In the Ming dynasty, the revivalist scholars have often mimicked ancient people that they have usually received negative criticism. How they, being aware of this issue, have proposed theories to solve the problem is the core issue addressed in this article. To achieve this goal, it is a must to pay special attention to Xu Xue-Yi’s criticism of Du Fu’s poetry in his Tracing the Origins and Distinguishing the Types of Poems. This article examines the content of Xu’s criticism, cross-references traditional views, and thereby highlights the significance of his viewpoints. It finds that Xu has made a detailed classification that features description and evaluation of Du’s poetry with arguments of high importance. For example, Xu deems that Du’s poetry is both traditional and creative and Du attaches great importance to xing ‘implied comparison.’ He also notes that Du and high-Tang poetry have the same value. His innovative arguments can solve the problem of the revivalist imitation of ancient poetry and are also a precursor of Wang Yu-Yang’s theories.