Sophistry, since Plato and Aristotle, has been philosophy's negative alter ego, its bad other. Yet sophistry's emphasis on words and performativity over the fetishization of truth makes it an essential part of our world's cultural, political, and philosophical repertoire. In this dazzling book, Barbara Cassin, who has done more than anyone to reclaim a mode of thought that traditional philosophy disavows, shows how the sophistical tradition has survived in the work of psychoanalysis. In a highly original rereading of the writings and seminars of Jacques Lacan, together with works of Freud and others, Cassin shows how psychoanalysis, like the sophists, challenges the very foundations of scientific rationality. In taking seriously equivocations, jokes, and unfinishable projects of interpretation, the analyst, like the sophist, allows performance, signifier, and inconsistency to reshape truth. This witty, brilliant tour de force celebrates how psychoanalysts have become our culture's key dissidents and register, in Lacan's words, "the presence of the sophist in our time."