Oliver Davis has published a new article on the work of philosopher Peter Sloterdijk, as part of a special issue of Angelaki on Sloterdijk, edited by Patrick Roney and Andrea Rossi. 'Anthropotechnical Practising in the Foam-World' can be accessed here. Abstract: I begin by acknowledging the profusion of Peter Sloterdijk’s published work, the suggestion by Bruno Latour that it may be on the side of design, and Sloterdijk’s pugnacious aversion to professorial critique. I focus on what I consider to be the crucial and vexed relationship between the general immunology of the Spheres trilogy [1998–2004] and the general ascetology of You Must Change Your Life [2009]. I present an analytical reconstruction of Sloterdijk’s account of originary spheric being-with in the trilogy, focused on its culmination in the foam-world; I suggest this account is too ambiguous on key matters of basic ontological structure and I question whether the foam metaphor is adequate as a description of intersubjectivity today. Against the backdrop of this discussion I consider whether the general ascetology of Sloterdijk’s second anthropotechnics involves practising in, or practising on, the shells of symbolic immunity and conclude the latter. Setting this alongside the trilogy’s insistence that cells in the foam are “co-fragile,” I argue that anthropotechnical practising in the foam-world is suffused with a violence which Sloterdijk is reluctant to theorize. Registering one significant undeclared context of his discussion of self-enhancement, in postmodern management theory, I suggest that successful anthropotechnical practising in the foam-world requires the capacity to ignore other people and their interests. I note that Sloterdijk’s one-eyed embrace of competitive self-enhancement in You Must Change Your Life has since been qualified in brief remarks in What Happened in the 20th Century? [2016] but not substantively reconsidered. In conclusion, I pay tribute to the anthropotechnical lesson of Sloterdijk’s theoretical project, notwithstanding its design flaws and continuity errors.