Abstract
In this paper I aim to examine Heidegger’s analysis of existential spatiality in Being and Time in the light of Sloterdijk’s criticism of it. Sloterdijk states in Spheres I that Heidegger presented, in Being and Time, an “embryonically revolutionary” approach to being and space but did not complete it. His own ‘Spheres Project’ would purport fill this gap. Based on the analysis of the fundamental moments of existential spatiality (§§12 to 28 and §70 of Being and Time), and taking into account comments made by Heidegger himself in later years, I will attempt to answer the question of the alleged unfinished character of the analysis of existential spatiality in Being and Time.