In Medieval Identity Machines, Jeffrey J. Cohen examines the messiness, permeability, and perversity of medieval bodies, arguing that human identity always exceeds the limits of the flesh. Combining critical theory with a rigorous reading of medieval texts, Cohen asks if the category "human" isn't too small to contain the multiplicity of identities. As such, this book is the first to argue for a "posthuman" Middle Ages and to make extensive use of the philosophical writings of Gilles Deleuze to rethink the medieval. Among the topics that Cohen covers are the passionate bond between men and horses in chivalric training; the interrelation of demons, celibacy, and colonialism in an Anglo-Saxon saint's life; Lancelot's masochism as envisioned by Chretien de Troyes; the voice of thunder echoing from Margery Kempe; and the fantasies that sustained some dominant conceptions of race. This tour of identity--in all its fragility and diffusion--illustrates the centrality of the Middle Ages to theory as it enhances our understanding of self, embodiment, and temporality in the medieval world.