Difference, Differend

English summary: Gilles Deleuze and Jean-Francois Lyotard are world-famous. We know that they were colleagues at the Centre Universitaire Experimental de Vincennes (1969-1980), where they, along with their friend Francois Chatelet, taught in the Philosophy Department for many years. Prior to that, they participated in the events of May '68, openly siding with the students and endeavouring to derive theoretical teachings from the movement. Two considerations need to be highlighted: first, it should be stressed that, although Deleuze's and Lyotard's mode of philosophical intervention was political, it was not confined that that realm. Examining a political issue involves a philosophical reading of the world and of what is, and is thus rooted in notional mechanisms for achieving systematicity. Therefore, from their parallel work on structuralism, they both recognised the need to confront the issue of language and discursivity. Yet they both ventured beyond structuralism: Deleuze by celebrating, with Guattari, unprecedented "nuptials" between Marxism and psychoanalysis, and Lyotard by constructing his recourse to the "figural," and later to a "libidinal economy," echoing Deleuze's and Guattari's ideas. It was during that era that the profile emerged of two thinkers united by their deep attachment to the "anarchy of desire" and eager to distance themselves from classic humanism. Through them, an entirely new theory of sensitivity was born, attested to by their uninterrupted dialogue with the arts of their time, from literature to the cinema, and from painting to the theatre. It would be wrong, however, to believe that Deleuze and Lyotard agreed on everything. Differences soon surfaced. Obviously, they had had different beginnings: while Lyotard was exploring phenomenology and Marxism, Deleuze was inventing a singular genealogy derived from unpopular authors of the philosophic tradition such as Hume, Bergson, Nietzsche or Spinoza. In the late 1970s, after having grown close, differences over their respective thoughts and actions split them apart. French description: Gilles Deleuze et Jean-Francois Lyotard sont deux figures centrales de la pensee francaise contemporaine. Leur connivence, nee dans les annees 1970 alors qu'ils enseignent a l'Universite experimentale de Vincennes, procede d'une critique partagee de l'humanisme classique, d'une distance comparable a l'egard du structuralisme, enfin d'une thematisation commune du desir et de la sensibilite. La publication, a deux ans d'intervalle, de L'Anti-OEdipe et d'Economie libidinale confirme cette proximite: les auteurs y soutiennent des positions ethiques et politiques tout aussi intempestives.On aurait pourtant tort de croire que leurs idees relevent d'une meme philosophie de la difference, expression qui caracterise la seule entreprise de Deleuze. Des les annees 1980, Lyotard et Deleuze ont en effet diverge sur le sens a accorder a la psychanalyse, a l'oeuvre de Wittgenstein ou encore a l'obligation morale.Le propos du present volume est de mettre a profit quarante annees de recul pour confronter a nouveaux frais ces deux representants de la philosophie francaise, en restituant l'heritage, l'evolution et le prolongement de leurs pensees respectives. Les contributions ici reunies deploient le large eventail des disciplines que Deleuze et Lyotard ont explorees et discutees. Elles s'interessent aussi bien a la periode de leur plus grande proximite theorique qu'a l'apparition des differends les opposant, au moment meme de l'avenement, chez Lyotard, du concept de differend .