Abstract Having both similarities with and differences from dao 道, yi 一 is an important concept which occupies an important position in early Daoist thought. As is the case with dao, “oneness” can also be traced back to the Laozi and subsequently went through a complex process of conceptual change. As a foundational concept, it serves as a description of dao while also referring to the innermost basis for the emergence and unity of everything that exists. As the foundation of the dao of political authority and effective governance, “oneness” refers to a basic principle and method which the ruler should grasp and put into practice 執一, but also designates an elementary goal and value in the ruler’s own process of self-cultivation 貴一. In comparison to the idea of dao, the concept of “oneness” approaches the relation between the one and the many as entailing a rich variety of relations of identity/difference and commonality/diversity which manifest themselves within the myriad things and affairs in the world in a more direct manner.