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).
Joachim Ritter
Ritter is considered one of the most influential philosophers in postwar West Germany. Among his disciples were scholars and public intellectuals like Ernst-Wolfgang Böckenförde, Max Imdahl, Hermann Lübbe, Odo Marquard, and Robert Spaemann. Together with them, Ritter started the „Historisches Wörterbuch der Philosophie“ and contributed to development of conceptual history in the field of philosophy. In the 1980s, Jürgen Habermas opposed the Ritter School for being leading representatives of German neo-conservatism. More recent scholarship in intellectual history points out Ritter's seminal role for the modernization of German political thought and the development of a modern liberal republicanism.