「玄」、「元」在文字訓詁上曾有通假之用例，依此用例「玄學」即為「元學」，「元學」即「本元之學」、「本體之學」。在中國哲學史建構的過程中，魏晉玄學之學科屬性，大抵傾向被定位為「本體論」的「本末有無」之辨，並依此定位，而與漢代之氣化宇宙論有所區隔。但學界對魏晉玄學的主要議題或持另一觀點，即視之為「名教自然」的論爭過程。依王國維的說法，中國哲學家多即為政治家，則中國哲學觀點的提出，背後往往另涉及政治議題，則「有無之辨」與「名教自然」實二而一。然而，依現今玄學史之論述，名教自然的思想進程往往以「名教本自然」、「越名教而任自然」、「名教即自然」標示之，與本體論有無的關係既未能呈現，其「自然」亦多有歧義而失之含混。儘管依貴無之風，易失之流蕩，但無論本體論上主貴無或崇有者，對名教基本皆持肯定之態度，故而此「自然」顯然兼蓄「有無」二義。但「有無」二者仍可再為細說，為此，本文嘗試以「名教」問題為切入點，將其本體論基礎區分為「本無」、「任心」、「足性」、「崇有」四種形態。依此區分，可說明王弼「本無」之說或可於《禮記．樂記》、《淮南子》等思想脈絡，而嵇康「元氣陶鑠，眾生稟焉」之說亦為漢代氣化思想之延續。同時依氣性稟賦之真實性情，率性任心而建立其真實名教；亦依氣性材質差異而建立其名教制度之合理性。再依王弼、裴頠思想之比較，裴頠之「有」乃一「道之全者」，於此義與王弼之「無」實同出而異名。此區分一方面說明魏晉玄學與漢代思想所承繼的部分，並稍可鉤勒其思想脈絡之演變；一方面對「自然」在魏晉玄學中的數種歧義，亦試圖釐清之。

The word “Xuan” is used as “Yuan” which means the beginning; thus Xuanxue is understood as ontology. In the constructional process of Chinese philosophy, Wei and Jin Xuanxue is defined to be dialectic ontology, being and non-being. According to the definition, Xuanxue is distinguished from the Qi-inclined cosmology in Han dynasty. However, another main subject of Xuanxue is considered as debates on social relationships and human nature. Chinese philosophy is always involved with politics; consequently, the dialectic ontology cannot be divided from the debates on social relationships and human nature. According to popular narration in the history of Xuanxue, the process of teachings on social relationships is divided into three sections: based on nature, transcended by nature, equal to nature. In this kind of narration, “nature” is not only ambiguous, but also lack of the relationship with ontology. Those who are inclined to being or non-being both agree with the existence of teachings on social relationships; thus “nature” includes both being and non-being. Accordingly, from the angle of teachings on social relationships, this essay divides Xuanxue into four ontological forms: non-being, self-judgment, natural property and being. Besides, Wangbi’s “ non-being” could be said to derive from Liji and Hainazi, and Jikang’s yuanqi（ontological vitality） could also be said to be the continuation of the Qi-inclined cosmology in Han dynasty. Therefore, with the division of four ontological forms, the continuation of thinking in Han dynasty and the ambiguity of nature may be both explained.

清靜之性;無;有;氣;名教;自然

nature of purity; Xuan; non-being; Qi; teachings on social relationships; nature