AbstractThis article constitutes one of the first comparisons between the philosophies of Peter Sloterdijk and the philosophical tandem Gilles Deleuze-Félix Guattari. The subject of the discussion between both philosophical positions is on communication with the exterior, and thus also how an interiority is to be conceived. Both philosophers raise these questions in reference to the work of the Estonian biologist Jacob von Uexküll. At first sight, Sloterdijk’s focus on immunity mechanisms seems to suggest a preference for restricting this communication, whereas Deleuze and Guattari’s interest in becomings seems to direct us in the opposite direction. However, a closer examination of both positions reveals that the difference lies in the nature of their approaches: whereas Deleuze and Guattari’s interest in opening up interiorities is ontologically motivated, Sloterdijk’s focus on shielding them off is existential. These findings might help us in demining the opposition between progressive socialism and conservatism.