Deleuze's central project is to invent new images of thought to put in place of the classical system of representation of theoretical thought.
For D+G, philosophy is at once the creating of concepts and instituting of the plane of immanence. (What is Philosophy?, p.41) (see also science / philosophy) According to Deleuze, " Immanence is the very vertigo of philosophy." (Expressionism in Philosophy, p. 180, quoted in Giorgio Agamben, "Absolute Immanence" in Potentialities, p. 226) Giorgio Agamben, calls Deleuze's book, What is Philosophy?, the theory of this vertigo.
Still, the plane of immanence remains one of their more ineffable concepts. Deleuze calls the plane of immanence (or of consistency) "the image of thought." It is immanent not to something but only to itself. "Whenever immanence is interpreted as immanent to Something, we can be sure that this Something reintroduces the transcendent." (p.45) The plane of immanence is "prephilosophical" not in the sense of being preexisting but in the sense of not existing outside philosophy even though philosophy presupposes it. (p.41) (Derrideans take note) The plane of immanence appears as both what must be thought and what cannot be thought: "Perhaps this is the supreme act of philosophy: not so much to think of THE plane of immanence as to show that it is there, unthought in every plane, and to think it in this way as the outside and inside of thought, as the not-external outside and the not-internal inside."( What is Philosophy?,pp 59-60)
As usual, Deleuze and Guattari's figures form a continuous chain or loop. Thus: Becomings and multiplicities intersect the plane of immanence or consistency, "the intersection of all concrete forms....It is the abstract Figure, or rather since it has no form itself, the abstract machine of which each concrete assemblage is a multiplicity, a becoming, a segment, a vibration." (plateaux p.251-2). The plane of consistency or of composition of haecceities which knows only speeds and affects. "There is therefore a unity to the plane of nature, which applies equally to the inanimate and the animate, the artificial and the natural." (254) "This is not animism, any more than it is mechanism; rather, it is universal machinism."
The plane of immanence constitues "the absolute ground of philosophy, its earth or deterritorialization, the foundation on which it creates its concepts." The plane of immanence presents two sides to us, extension and thought, or rather two powers, the power of being and the power of thinking. The plane of immanence is surrounded by illusions, by thought's mirages, that rise from the plane itself like vapors from a pond. (p.49) According to Giorgio Agamben, "In Deleuze the principle of immanence functions antithetically to Aristotle's principle of the ground." ("Absolute Immanence" p.233) "The figure of immanence is precisely what can never be attributed to a subject, being instead the matrix of infinite desubjectification.
Immanence is opposed to transcendence, vertical Being, imperial State in the sky or on earth, where there is religion. molarization involves the creation of the plane of transcendence (also called the plane of organization.)
According to Brian Massumi, the plane of consistency is the phase space of a system. Would it be more accurate to call it the phase portrait? Or is a phase portrait the diagram ?
Michael Hardt and Antonio Negri call the discovery of the plane of immanence "the primary event of modernity." (Empire, p. 71) They describe this event as the "affirmation of the powers of this world," when "humans declared themselves masters of their own lives, producers of cities and history, and inventors of heaven." In those origins of modernity, knowledge shifted from the transcendent plane to the immanent. Knowledge became a doing, a practice of transforming nature. The powers of creation that had previously been consigned exclusively to the heavens were now brought down to earth. This revolutionnary change refigured the idea of authority and defined a tendency towards a democratic politics by posing humanity and desire at the center of history. According to Hardt and Negri, this new emergence provoked a reaction, in fact, a war. The revolution of European modernity ran into its Thermidor. (p.75) The forces of order reestablished ideologies of command and authority. Thus modernity itself came to be defined by a crisis. And Eurocentrism became a war on two fronts -- against the revolutionnary forces within Europe and against the non-European world.
Like Marx and Engels, Hardt and Negri put metaphysics in a political frame. They see the assertion of immanence as radical, in fact revolutionnary, assertion of creativity and self-determination. Thus the revivals of transcendence as mediation are counterassertions of authority. The intellectual history of the Renaissance, the Reformation, and the Counter-reformations are just as much part of the new Eurocentric politics as are the conquests of the "new world."
In What is Philosophy?, D+G describe the plane of immanence as "a section of chaos that acts like a seive. For them the plane of immanence is interleaved with a multitude of layers that are sometimes separate and sometimes knit together. (it is for this reason that they call philosophical time "stratigraphic" and describe it as a fractal surface.)
The plane of immanence is perhaps thought's strange attractor.