唐高道王玄覽（626-697）《玄珠錄》之興起，適逢唐代「佛、道論諍」下之重玄思潮，重玄思想的論題，不論在古代或當代，頗受到注目而尚有諍議的是：重玄之道，是否為形上實體？《玄珠錄》融攝佛、道，一方面繼承《老子》要義、一方面消融佛學空義，「道體」的問題重新再被顯題化，佛教基於性空義之「反」形上學式的思考，不斷質疑道教「道體（重玄之道）」的觀念，究竟是「實有」還是「假有」，是「有體」還是「無體」，此一核心問題的答案，不但在唐代重玄思潮下成玄英、李榮、唐玄宗、杜光庭等人之「老莊《注》《疏》」中逐漸被顯題化，更於唐初王玄覽《玄珠錄》的體系中重新受到檢視，得到頗為深刻地理論闡發。他發展出一種「新道論」，其特出之處在於「以空為體」的「道體」論觀念及「性無常性」之「體道」思想，突顯唐代重玄之道的觀念轉折與詮釋上之突破。本題藉此反思重玄之「道」是否為現代學術用語下之「形上實體」，其間所引發的詮釋間距或視域融合之態勢，相信不論對於古典或當代的「道」之詮釋，不僅於唐代重玄思潮中，具有「轉折性」意義，或富有具參考性的當代詮釋之反思性價值。

The rise of Wang Xuanlan’s 王玄覽 (626-697) Xuanzhu lu 玄珠錄 coincided with the Chongxuan 重玄 (Twofold Mystery) trend of thought under contentions between Buddhism and Daoism in the Tang dynasty. Concerning the topic of the Chongxuan school, whether in ancient or contemporary times, a number of questions and criticisms have persisted and continue to attract much attention: Is the Dao of Chongxuan the ultimate substance of the universe? Xuanzhu lu integrates Buddhism and Daoism by, in one regard, inheriting the essentials of Laozi, and in another, dissolving the emptiness of Buddhism. Moreover, the issue of “Daoist substance” 道體 is re-emphasized. Buddhism is based on the “anti”-metaphysical thinking of emptiness, which incessantly questions the Daoist notion of “Daoist substance” (the Dao of Chongxuan), whether it is “being”/“non-being” or “entity”/“non-entity.” The answer to this core question not only lies with the Chongxuan ideological trend of the Tang dynasty, exemplified by Cheng Xuanying 成玄英, Li Rong 李榮, Tang Xuanzong 唐玄宗, Du Guangting 杜光庭, and others who gradually became prominent from interpretations of both Laozi and Zhuangzi, but is also reinterpreted with a remarkable theoretical understanding within the system of Wang Xuanlan’s Xuanzhu lu from the early Tang dynasty. He developed a “new Daoism,” which is unique in its interpretation of “Daoist substance” as “emptiness as substance” 以空為體 and for the impermanence of Daoist nature, highlighting the conceptual transitions and interpretations regarding Daoist theory of the Tang dynasty. In this way, this topic of interest has led to reflections on whether the Dao of Chongxuan is a “metaphysical substance” in modern academic terms and on the gaps concerning interpretations or the amalgamation of fields caused by it. This study thus maintains that interpretations of Dao, regardless of being classical or contemporary, not only possess a “transitional” significance pertaining to the Chongxuan school of the Tang, but are also brimming with referential reflections on contemporary understandings.