The opening chapter of the volume investigates the (im)possibility of posthuman and/or posthumanist literature by drawing on the insights of (critical) posthumanism on the one hand, and on literary structuralism, narratology, and Roman Jakobson’s factors of communication on the other hand. First, the chapter aims to discuss and settle some recurrent confusions around the theories of posthumanism and the concept of posthuman. Then, the chapter’s author, Carole Guesse, turns to discussing the concept of literature and the posthuman(ist) potentialities of each of its components and participants: the author, the reader, the text, the context, language, medium, and their various aspects. The chapter concludes with a brief case study on Michel Houellebecq’s The Possibility of an Island (2005), a novel that could be considered an example of both posthuman and posthumanist literatures due to its genetically engineered clone-narrators – which may furthermore be addressing clone-narratees. In the light of Jakobson’s communication model, these part-human part-nonhuman characters affect the narrative and its meanings in various ways. Overall, the chapter participates in the timely discussion concerning the possible functions posthumanism and the posthuman could serve in literary research: are they efficient or meaningful tools of literary analysis, and conversely, can literary analysis provide new, relevant understanding of posthumanism or the posthuman?