This paper attempts to clarify Heidegger’s concept of metaphysics as it is developed in the period immediately after the publication of Being and Time. According to Heidegger, the concept of metaphysics contains two different tasks: the question of Being as such (Sein als solches) and the question of being asa whole (Seiende im Ganzen). These two tasks correspond to Fundamental Ontology and Metontology. Based on this distinction, I argue that the concept of metaphysics introduces a fundamental change in the philosophical project of Being and Time. Firstly, I show in what sense Fundamental Ontology can be understood as an immanent critique of Phenomenology, which attempts to overcome an omission in its account of the transcendental field. Secondly, I argue that Metontology should not be taken as an attempt to develop regional ontologies lacking in Being and Time, but as a new philosophical task concerning the world as being as a whole. However, this task cannot be considered on the basis of the concept of world presented in Being and Time. Metontology is concerned with a new account of the phenomenon of nature and of Heidegger’s concept of facticity, which goes beyond the boundaries of the Analytic of Dasein.
