H. P. Grice's theory of implicature provides the leading paradigm for research in pragmatics. Wayne Davis argues controversially that Gricean theory does not work. In developing his argument the author explains that the psycho-social principles actually define the social function of implicature conventions, which contribute to the satisfaction of those principles. By offering a searching and systematic critique of one of the established doctrines in the philosophy of language, this challenging book will be of particular importance to philosophers of language and linguists, especially those working in pragmatics and socio-linguistics.