Xuanxue, often called Neo-Daoism, was developed by thinkers such as Wang Bi and Guo Xiang, who wrote influential commentaries on the Laozi, Zhuangzi and Yijing. They debated being and non-being, the root and its traces, and shaped the vocabulary in which Buddhism was received in China.
Xuanxue
Learning of the mysterious: the metaphysical revival of Daoist thought in third- and fourth-century China.
Also: Neo-Daoism, Profound Learning