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).
Duns Scotus
John Duns, commonly called Duns Scotus (; ; 1266 – 8 November 1308), is generally considered to be one of the three most important philosopher-theologians of Western Europe in the High Middle Ages, together with Thomas Aquinas and William of Ockham. Scotus has had considerable influence on both Catholic and secular thought. The doctrines for which he is best known are the "univocity of being", that existence is the most abstract concept we have, applicable to everything that exists; the formal distinction, a way of distinguishing between different aspects of the same thing; and the idea of haecceity, the property supposed to be in each individual thing that makes it an individual. Scotus also developed a complex argument for the existence of God, and argued for the Immaculate Conception of Mary.