「天人關係」乃是中國哲學一哲學範疇，更是主要的範疇。由於「天人關係」是《莊子》與《黃帝四經》共同都有的哲學範疇，故我們可以從此一範疇來辨析兩者的不同。所謂「天人關係」概指自然界與人的關係，本文以為最原初的討論應從作為主體之人對於作為客體之自然界的認識來探索此一議題。本文目的在於從「認識」方面來探討《莊子》和《黃帝四經》的「天人關係」，也就是從「客體與主體」來看「天與人」，其主體反映客體所呈現出的思想型態是屬於具象、想像或抽象的思想？並以此探討兩者不同的認知定向。
本文研究方法是根據文本對關於主題的概念作清楚的分析，並對相關命題作邏輯的論證，簡言之即「持之有故，言之成理」。因為，哲學的研究對象是思想，而思想是由概念、命題等構成的，故我們須釐清概念，而後以邏輯來論證命題。
就客體之「天」而言，《黃帝四經》的「天」是物理之天，是外在經驗世界，而《莊子》的「天」包括外在的物理之天，但更強調內在精神的天－天然狀態。就主體之「人」而言，從認知能力來說，《黃帝四經》肯定人的認知能力有感性與理性，《莊子》則認為除了感性與理性之外，人還有直觀的能力。由此，兩者從客體所反映出對於「天」的認識便不完全相同，《黃帝四經》由感官感覺出發而後以理性歸納出「天道」的概念，這是物體的第二性質；對於外在世界，《莊子》肯定我們可以由感官感覺出發而後以理性歸納出「天然」的概念，這是物體的第三性質或一種關係共相，但是感官和理性卻不能認知內在精神的「天然」，只能藉由直觀來體認。就關於「天」這類知識的本質來說，由以上之天人關係中，我們可以分辨《黃帝四經》的知識論定向是「實在論」的，而《莊子》的知識論定向則有「主觀觀念論」的傾向。
Can we really make a direct link between nature and man? “The relation between Nature and Man”fits into a major category of Chinese Philosophy. We can differentiate the orientations between Chuang-tzu and The Yellow Emperor’s Four Texts on the basis of “The relation between Nature and Man”, because it is the common philosophic category of both books. What is called“The relation between Nature and Man” generally refers to the relation between the natural world and human beings. I think we should discuss this issue from a fundamental point of view that how a human (a perceiving subject) perceive the natural world (a perceived object). This paper is aimed at researching into“The relation between Nature and Man”of Chuang-tzu and The Yellow Emperor’s Four Texts from the point view of “perception”, namely to regard“Nature and Man”as“Object and Subject”. There are three types of thought: the concrete, the imaginary, and the abstract thought. What is the type of thought that the subject reflects the object in Chuang-tzu and The Yellow Emperor’s Four Texts? Further, we can differentiate the orientations of perception between these two books.
The conclusion of this paper is that, regarding“the nature of knowledge” about“Nature”, the epistemological orientation in The Yellow Emperor’s Four Texts is realism, but that in Chuang-tzu is subjective-idealism in some respect.
