On the Becoming of Concepts

What is Deleuze's concept of a concept?In What is Philosophy?, Deleuze and Guattari famously define philosophy as an activity that consists in "forming, inventing, and fabricating concepts."Deleuze seems to have held to this conception of philosophy as the creation of concepts from the very start of his career."The power of a philosophy," he wrote in one of his early books, "is measured by the concepts it creates, or whose meaning it rejuvenates—concepts that impose a new set of divisions on things and actions."Even in high school, he recounts, when he was first introduced to philosophy, concepts struck him with the same force as literary characters, having their own temperament and vitality, and populating their own landscapes (ABC E). It was not until late in his life, however, in What is Philosophy? (1991), that Deleuze, working with Guattari, finally proposed his own "analytic of concepts," to borrow Kant's phrase, reaching the point where he could ask, "What have I been doing all my life?"Deleuze compared the book, in passing, to Kant's Critique of Judgment, and the comparison is an apt one: both are works of old age, written at a time when thinkers often have little new to say, their "systems" already being well established.Yet Kant's third critique is a book bristling with new concepts, pushing at the limits of Kant's carefully constructed architectonic, and setting the stage for Romanticism and what we now call, precisely, post-Kantian philosophy. In a similar manner, What is Philosophy?, far from being the self-reflective culmination of Deleuze's career, is much more his bequeathal to future philosophy, a handing-off of the baton; it too poses a plethora of new concepts and problems that are no doubt destined to be taken up by whatever a post-Deleuzian philosophy turns out to be.