It is not only for his own sake that Gilles Deleuze, along with Félix Guattari, insists that philosophy is the creation of concepts. This definition of philosophy is itself a concept and, as such, one of Deleuze and Guattari's major contributions to the field. It is no simple platitude, for the creation of a concept is a complicated endeavor. There is movement in a concept, and to think philosophically, in the way Deleuze proposes, is to move with it-not to bring it to a halt, but to ride it. Moreover, to make a contribution to philosophy is not to complete a concept, but to set it in motion, that it may continue its mutations in the future. It would seem that a most faithful engagement with Deleuze's thought would be one that is itself conceptually creative, one that does more than observe and explicate or contextualize one or another of his philosophical lines of flight. The creation of concepts is ongoing and open, and it is a task that Deleuze urges all who would "do philosophy" to take up; he himself invites those who read him to think with and beyond him, more so than about and according to him