Gilles Deleuze, an important figure in post-war French philosophy, began his career with a number of idiosyncratic yet rigorous historical studies of figures outside of the continental tradition in vogue at the time, before writing some of the more infamous texts of the period, in particular, Anti-Oedipus and A Thousand Plateaus. These texts collaborative works with radical psychoanalyst Félix Guattari. Deleuze is a key figure in what is known as 'postmodern' thought. Considering himself an empiricist and a vitalist, his body of work, which rests upon concepts such as multiplicity, constructivism, difference and desire, stands at a substantial remove from the main traditions of 20th century Continental thought. His thought locates him as an influential figure in present-day considerations of society, creativity and subjectivity. Deleuze also published widely on literature, psychoanalysis and art.
Deleuze's whole intellectual trajectory can be traced by his shifting relationship to the history of philosophy. While in later years, he became quite critical of both the style of thought implied in narrow reproductions of past thinkers and the institutional pressures to think on this basis, Deleuze never lost any enthusiasm for writing books about other philosophers, if in a new way. Most of his publications contain the name of another philosopher as part of the title: Hume, Kant, Spinoza, Nietzsche, Bergson, Leibniz, Foucault.
Deleuze expresses two main problems with the traditional style and institutional location of the history of philosophy. The first concerns a politics of the tradition:
The history of philosophy has always been the agent of power in philosophy, and even in thought. It has played the repressors role: how can you think without having read Plato, Descartes, Kant and Heidegger, and so-and-so's book about them? A formidable school of intimidation which manufactures specialists in thought - but which also makes those who stay outside conform all the more to this specialism which they despise. An image of thought called philosophy has been formed historically and it effectively stops people from thinking. (D 13)
This hegemony of thought recurrently comes under attack later in Deleuze's career, notably in What is Philosophy? This criticism also sits well with a general theme throughout his writings, which is the immediate politicisation of all thought. Philosophy and its history is not separated from the fortunes of the wider world, for Deleuze, but intimately linked to it, and to the forces at work there.
The second criticism directed at the traditional style of history of philosophy, the construction of specialists and expertise, leads directly to the foremost positive aspect of Deleuze's particular method: "What we should in fact do, is stop allowing philosophers to reflect 'on' things. The philosopher creates, he doesn't reflect." (N122) And this creation, with regard to other writers, takes the form of a portrait:
The history of philosophy isn't a particularly reflective discipline. It's rather like portraiture in painting. Producing mental, conceptual portraits. As in painting, you have to create a likeness, but in a different material: the likeness is something you have to produce, rather than a way of reproducing anything (which comes down to just repeating what a philosopher says). (N 136)
Perhaps such a method does not seem extremely creative, or perhaps only in a relatively passive sense. For Deleuze, however, the history of philosophy also embraces a much more active, constructive sense. Each reading of a philosopher, an artist, a writer should be undertaken, Deleuze tells us, in order to provide an impetus for creating new concepts that do not pre-exist (DR vii).
Thus the works that Deleuze studies are seen by him as inspirational, but also as a resource, from which the philosopher can gather the concepts that seem the most useful and give them a new life, along with the force to develop new, non-preexistent concepts.
In an important sense, Deleuze's whole modus operandi is based in this revaluation of the role of other thinkers, and the means by which one can use them: each of his books either centers around one philosopher, or derives much of its texture from references to others. In any case, new concepts are derived from others' works, or old ones are recreated or 'awakened', and put to a new service.