Wang Bi
The various philosophical positions of Taoism can also be viewed as non-theistic about the ultimate reality (Tao). Taoist philosophers have conceived of different ways of describing the ultimate nature of things. For example, while the Taoist Xuanxue thinker Wang Bi argued that everything is "rooted" in "Wu" (non-being, nothingness), Guo Xiang rejected "Wu" as the ultimate source of things, instead arguing that the ultimate nature of the Tao is "spontaneous self-production" ("zi sheng") and “spontaneous self-transformation” ("zi hua").