His early books were studies on Spinoza, Hume, Kant, and Bergson. While they were monographs that tried to preserve the classical tradition, as much as an attempt to use them in new ways and go beyond them, they all were written from an angle entirely foreign to the "received exegetical wisdom."
Deleuze reads with an eye for heretical doctrines (Spinoza’s ontology of bodily affects/forces & Hume’s radical empiricism) which retain the power to provoke/disconcert. Also his study on Nietzsche instituted a love affair between Nietzsche and the French in the mid 20th century. Great heroes (Nietzsche and Spinoza) stand for counter tradition of skeptical, affirmative, nonsubjectcentered, instinctually driven "desiring-production" (see Ronald Bogue's "Deleuze & Guattari") Some insist that Deleuze’s philosophy should be seen as the revamped version of Bergsonism. Bergson rebelled against the Cartesian tradition with the claim that there was no distinction whatever between mind and body, and the monist conviction that all that exist was "movement of matter". Deleuze said as much, claiming that the body and the brain constituted a "material continuum", which was in contact with the external world and his conception of desire parallels Bergson’s "élan vital". In "Rhizome: Introduction", Deleuze (with Felix Guattari) compared the multiplying jungle of desire to the underground root system of a rhizome, like that of a couch-grass. Most models of knowledge are based on the tree model with a single root, which entails a foundationalist model, but Deleuze chose the metaphor of a rhizome that spread into all directions, forming an anarchic network where every point could be connected to any other point.
"Différence et repetition" (Deleuze’s doctoral dissertation) & "Logique du sens" come close to a full-scale programmatic statement of post-philosophy, antisystematic, ultranominalist or resolutely nontotalizing mode of thought. Deleuze focuses his philosophical energies on two well-worn topics: identity and time, as well as the nature of thought in the "Difference and Repetition". Immanence, a chief conceptual tool of Deleuze’s radical empiricism, refers to a philosophy of the empirical real or the flux of existence that lacks a transcendental level or some fundamental fissure. The ontological sense of the immanent is that there is only one substance. Ergo everything that exists must be reflected on the same level, the same rank, and analyzed by their relations instead of their “essences.” The other key conceptual tools are constructivism and excess. In the "Logic of Sense", Deleuze explored the boundaries of meaning and non-meaning with several readings on different texts by the Stoics, Plato and Lewis Carroll.
The collaboration with political theorist Felix Guattari, similar in spirit to late '60's antipsychiatry movement, resulted in two books "Anti-Oedipus" and "A Thousand Plateaus". Anti-Oedipus is a joint diatribe, a vast chaotic potpourri book that attacks Freudian psychoanalysis as well as the Lacanian poststructuralist adaptation for being the instrument of channeling/policing the flow of itinerant "molecular" desire which reinforces the "molar" prescriptions of the capitalist sociopolitical order. These attacks also established the 1970’s as the decade of the philosophy of desire. To be brief, Freudian psychoanalysis was heavily subject to the following criticism:
- for being excessively reductionist in its simplification of everything into a fundamental oedipal triangle
- for celebrating a conventional and repressive family structure
- for compelling multidimensional desire into constricted and restrictive canals.
The failure of psychoanalysis to recognize the many natures of desire leads to reductionism where multiplicity is reduced to unity and the proliferation of meaning is deciphered by oedipal complex
Instead of Freud’s theatrical vision of the unconscious and Lacan’s linguistic vision of an unconscious structured like language, Deleuze and Guattari proposed the metaphor of a factory containing "desiring machines". Guattari intended the idea of machine as the indication where desire begins production at the stage where there is "no question of a structure or a subject position or coordinates of references." The Anti-Oedipus begins by describing a desiring machine: an organ machine connected to a source machine that emits a flow. E.g., a breast is the machine that produces milk and the mouth is the machine connected to it. Many literary allusions are used to explain the function of these desiring machines, such as the following: "under the skin, the body is an overheated factory;" Kafka's writing machine from "In the penal Settlement"; Beckett's narrator's construction, the machine from "Molloy".
The last collaborative work, "What is Philosophy", very different from the iconoclastic books of the 70's, attempts to answer the title by stating that, contra the traditional models of contemplation, reflection or communication, philosophy is a discipline that creates concepts. The entire history of philosophy contains "signed concepts" (e.g., Descartes' cogito or Leibniz' monads) because philosophers are "friends of concepts." Science, in this respect, generates propositions and functions, whereas art is composed of words, color or sounds that "capture and encode sensory perceptions."
Mackenzie insists that there is a strain of continuity throughout Deleuze's works where he constantly emphasizes creativity within all domains, and a rejection of philosophy as mere contemplation.