The book explores the way in which apophatic discourse of negative theology has illuminated contemporary critical theory. It demonstrates the significance of apophasis both in Jacques Derrida's search for a "new language", responsive to singularity and alterity, and in the analyses of the experience of transgression, developed by Maurice Blanchot, George Bataille and Michel Foucault. Following Derrida's understanding of negative theology as a transgressive concept that transcends the linguistic, historical and religious contexts from which it arises, the book proves that apophasis is not merely a discourse on language restricted to one theological tradition, but should be viewed as a mode of dialogue and openness, essential to all responsible thinking.