 Like Ji Kang, Ruan Ji focuses on the concept of ziran, naturalness, in his reformulation of Daoist philosophy. Commenting on the Laozi, Ruan makes clear that the concept of Dao should be understood as the “self-so” source of the processes of change and transformation. Whereas the Laozi calls it Dao, the Yijing describes it as the “Great Ultimate” (taiji), and the Spring and Autumn Annals, the “Origin” (yuan). Or, as Ruan writes in his essay on the Zhuangzi, “heaven and earth are born of ziran, and the myriad beings are born of heaven and earth.” There is “nothing outside” (wuwai) the world of ziran, Ruan adds, which is to say that the Dao should not be mistaken for any metaphysical agent or entity. Rather, the theory of naturalness suggests that heaven and earth and everything within it originate from one qi. All phenomena are constituted by qi; as such, according to Ruan, Zhuangzi is surely right in maintaining that “the myriad beings are but one body” (Zhuangzi, Chapter 5).