Man and World 29: 315--326, 1996. 315 (~) 1996 Kluwer Academic Publishers. Printed in the Netherlands. Concept and event PAUL PATTON Department of General Philosophy, University of Sydney, Sydney, NSW 2006, Australia A Thousand Plateaus is a bewildering text, as much for its profusion of idiosyncratic terminology as for its apparent lack of any overall structure or argument. Take for example the plateau which deals with language, "Novem- ber 20, 1923 -Postulates of Linguistics": in the course of a discussion which touches upon speech act theory, the nature of indirect discourse, Stoic philos- ophy of language, Chomsky, sociolinguistics and a range of literary figures, Deleuze and Guattari reject a series of widely accepted postulates of linguistic theory and philosophy of language. These include the notion that language serves primarily to inform or to communicate and the notion that language is a more or less homogeneous system. In the course of their argument, they intro- duce a series of neologisms, including "order-word", collective assemblages of enunciation, incorporeal transformations and processes of deterritorial- ization and reterritorialization. Their purpose in doing so is not to provide an alternative linguistic theory, nor even a philosophy of language in any familiar sense of that expression. Rather, in the terms of the conception of philosophy which they outline in What is Philosophy?, Deleuze and Guattari are here engaged in the creation of a concept: language defined as "the set of all order-words, implicit presuppositions or speech acts current in a language at a given moment", z This is a definition of language in terms of its effectivity or command function: language as the systematic production of utterances which express a given set of incorporeal events. In an interview which accompanied the publication ofA Thousand Plateaus, Deleuze described this book as "philosophy, nothing but philosophy, in the traditional sense of the word". 2 However, as he and Guattari show in What is Philosophy?, the underlying conception &philosophy is far from traditional. On their view, the peculiar skill of philosophers lies in the creation of new concepts, where "concept" is a technical term which serves to distinguish philosophy from science and art. Science aims at the representation of states of affairs by means of mathematical or propositional functions. Art does not aim at representation at all but at the capture and expression in a given medium of"blocks of sensation". Philosophy falls somewhere in between : it is like science in that it fulfils a cognitive rather than an affective function,