Eastern philosophy
The "Dao De Jing" ("Tao-Te-Ching," c. 4th century BCE), traditionally attributed to Laozi, and the "Nan Hua Jing" ("Zhuang Zi") are considered the key texts of the tradition. The first organized form of Taoism, the Tianshi (Celestial Masters') school arose in the 2nd century CE. Xuanxue ("deep learning", also "Neo-Taoism") was a major philosophical movement influenced by Confucian scholarship, which focused on the interpretation of the "Yijing," "Daodejing," and "Zhuangzi" and which flourished during the third to sixth centuries CE. The most important philosophers of this movement were He Yan, Wang Bi, the Seven Sages of the Bamboo Grove, Ge Hong and Guo Xiang. Thinkers like He Yan and Wang Bi focused on the deep nature of Tao, which they saw as being best exemplified by the term "Wu" (nothingness, non-being, negativity).
Chinese exploration
During the Three Kingdoms, travellers from Eastern Wu are known to have explored the coast. The most important were Zhu Ying (朱應) and Kang Tai, both sent by the Governor of Guangzhou and Jiaozhi Lü Dai in the early 3rd century. Although each wrote a book, both were lost by the 11th century: Zhu's "Record of the Curiosities of Phnom" ( , , "Fúnán Yìwù Zhì") in its entirety and Kang's "Tales of Foreign Countries During the Wu Period" ( , , "Wúshí Wàiguó Zhuàn") only surviving in scattered references in other works, including the "Shuijing Zhu" and the "Yiwen Leiju".