此論題起於近代莊學研究因胡適（1891-1962年）於民國8年(1919)出版之《中國哲學史大綱》卷上對知識論(epistemology)之運用，使得學界在研究方法上產生相應的變化。但此論在莊學研究之作用，胡適僅對此說明莊子「達觀主義」（該書亦稱「極端的守舊主義」）基調之由來，至於知識論與莊學本身如何在目的上相容？以及知識本身之性質及其產生之效用如何在莊學理論中作出適當定義？胡適以來之說法，除了形成特殊的研究路徑之外，其內容仍有討論之必要。本文即針對這些問題，作出進一步分析。本文結論之要旨有二：第一，胡適的先秦名學史概念已建構起今日研究莊學者不容迥避的論述主題，但胡適所引發有關先秦知識論史研究，大體說來終是圍繞在知識社會學的層面，使得當時形成知識與知識被人運用的社會條件逐一被學者釐出，這對反思莊書所訴求的可信知識，可提供定位(positioning)所需的邊界與排序依據。第二，時至今日，知識論應用於莊學研究已擴張到探討知識在莊學之作用上。就莊學本身的內在理路言，這項問題旨在證成知識性質及其有效之檢定乃是一項維繫莊子逍遙義的重要條件。因為莊子書既在建構一套與世俗有別的「方外」思想，勢須使「方外」成為人關於善的展望的恰當場所，才可確保莊學的內在價值。如此一來，莊子必得解決來自［方內」社群集體式的審議(collective deliberations)的挑戰；莊子對善的判斷若是經得起檢定知識之客觀判準，可使彼此在「外內不相及」的情況下，不至於被對方視為純粹的主觀和任意的奇思怪想，並讓「遊方之內者」有可能接受。換言之，莊子學說之本旨雖不繫於知識論，但有賴此一途徑證明其本旨之真義；胡適以知識論詮釋莊學所形成的研究路徑，銜接上莊學本身的這條理路。

Hu Shi (1891-1962) applied epistemology in his well-known book History of Chinese Philosophy published in 1919. That has greatly influenced the academic world in its study approaches for the past decades. Therefore, this paper aims at further examining such phenomenon. When applying epistemology to expound the philosophy of Zhuang-zi, Hu Shi could only explain where Zhuang-zi's optimism (also called as extreme conservatism in Hu's book') originated from. As for questions like how epistemology was compatible with the study of Zhuang-zi in their purposes or how the nature or effect of knowledge itself could produce proper definition for Zhuang-zi's philosophy have become hot debated issues thereafter. A great variety of scholarly explanations has formed a particular study path. However, their content needs further discussion. Hence, the purpose of this paper is to further analyze these questions. There are two main conclusions presented: first, Hu's view on the history of names during early Quin ( xian quin ming xue shi) has established the themes and topics that all the scholars today have to deal with. But the various studies of history of xian quin epistemology inspired by Hu mainly center on the aspect of sociology of knowledge. Accordingly, the criteria of knowledge formation and social conditions of knowledge application were discarded by many scholars. This may provide a borderline or sequencing order for positioning the credible knowledge highlighted by Zhuang-zi's writings. Second, as the time proceeds, the application of epistemology has been broadened to the discussion of how knowledge functions in the study of Zhuang-zi. When it comes to the inner texture of the study itself, such a query refers to the proof of the nature of knowledge and the determination of its effect. These two are the essential criteria of defining Zhuang-zi's concept of Xiaoyao. Zhuang-zi's writing aimed at establishing a thinking of somewhere out there different from all other conventions, so such a somewhere out there is to serve as a place for people to reflect on the goodness so that the inherent value of the study of Zhuang-zi can be maintained. Therefore, scholars also have to deal with the challenges from the collective deliberations of the here within. If Zhuang-zi's judgment of goodness could pass the objective criteria of knowledge, then though the out there and the here within don't share much in common, his philosophy will not be disparaged as something grotesque or bizarre out of mere subjectivity and arbitrariness; instead, it may be accepted by those who stand "here within" a social boundary.