What role is attributed to geological knowledge within the broader whole of the Encyclopaedia? Which perspective is adequate to make philosophical sense of geological knowledge? This chapter’s response to these questions consists in a three-step argument. First, for Hegel, geohistory is irrelevant to philosophy but not the particular ways in which geological regularities are determined. Second, it argues that geology is important for Hegel as it develops the emergence of formations and structures that do not have a strict precedent in the domains of mechanical physics and chemistry, even if they arise from them. These formations and structures have a unique unity of composition and appearance, they form a dynamical but stable entity. Hereby geological notions serve to develop a particular notion of instantiation and self-determination that mediates inanimate matter with organic life. Third, it argues that by means of said emergence of formations and structures and their global arrangement, geology provides us with the basic notion of environment that serves as a precondition for the emergence of organic life. Hereby geology for Hegel mediates inorganic matter with the purposiveness of organisms.