by Daniel Smith
2. The Idea of Sensibility: Differential Relations and Differences in Intensity. Already in 1790, Salomon Maimon, one of the first post-Kantians to return to Leibniz, had proposed an essential revision of Kant on precisely this point.15 Leibniz argued that a conscious perception must be related, not to a recognizable object situated in space and time, but to the minute and unconscious perceptions of which it is composed. I apprehend the noise of the sea or the murmur of a group of people, for instance, but not the sound of each wave or the voice of each person that composes them. These unconscious “molecular” perceptions are related to conscious “molar” perceptions, not as parts to a whole, but as what is ordinary to what is noticeable or remarkable; a conscious perception is produced when at least two of these molecular perceptions enter into a differential relation that determines a singular point.16 Consider, for example, the color green: yellow and blue can be perceived, but if their perception diminishes to the point where they become indiscernible, they enter into a differential relation (db/dy = G) that determines the color green; in turn, yellow or blue, each on its own account, may be determined by the differential relation of two colors we cannot detect (dy/dx = Y). Or consider the noise of the sea: at least two minutely perceived waves must enter into a relation capable of determining a third, which “excels” over the others and becomes conscious. These unconscious perceptions constitute the “ideal genetic elements” of perception, or what Maimon called the “differentials of consciousness.” It is such a virtual multiplicity of genetic elements, and the system of connections or differential relations that are established between them, that Deleuze terms an “Idea”: the relations are actualized in diverse spatio-temporal relationships, just as the elements are actualized in diverse perceptions and forms. A sign, in its first aspect, is thus an “effect” of these elements and relations in the Idea: a clear perception (green) is actualized when certain virtual elements (yellow and blue) enter into a differential relation as a function of our body, and draws these obscure perceptions into clarity.17
Deleuze suggests that Bergson, in The Creative Mind, had developed a somewhat parallel conception of the Idea, using the domain of color as an example. There are two ways of determining what colors have in common. Either one can extract from particular colors an abstract and general idea of color (“by removing from the red that which makes it red, from the blue what makes it blue, from the green what makes it green”); or one can make all these colors “pass through a convergent lens, bringing them to a single point,” in which case a “pure white light” is obtained that “makes the differences between the shades stand out.”18 The first case defines a generic “concept” with a plurality of objects, in which the relation between concept and object is one of subsumption, and the state of difference remains exterior to the thing. The second case defines a differential Idea in the Deleuzian sense. The different colors are no longer objects under a concept, but constitute an order of mixture in coexistence and succession within the Idea. The relation between the Idea and a given color is not one of subsumption, but one of actualization and differentiation; and the state of difference between the concept and the object is internalized in the Idea itself. White light may be a universal, if you will, but it is a concrete universal, a universal variation, and not a genus or generality. The Idea of color is like white light, which “perplexes” within itself the genetic elements and relations of all the colors, just as the Idea of sound could be conceived of as white noise.19
This notion of the differential Idea finds its complement in the concept of intensity: these elements and relations are necessarily actualized in an intensive magnitude. Kant himself had defined the principle of intensity in the “Anticipations of Perception”: we know a priori that the matter of sensations will have a degree of intensity and that this magnitude will change along a continuum starting from the point where intensity = 0.20 But since he defined the form of sensibility as extended space, Kant limited the application of intensity to the matter of sensible intuitions that come to fill that space. But Maimon, like Hermann Cohen after him, argued that since space as a pure intuition is a continuum, it is the form of space itself that must be defined a priori as intensive quantity; there is therefore an internal and dynamic construction of space that necessarily precedes the representation of the whole as a form of exteriority (which implies that space is actualized in a plurality of forms).21 In empirical experience, to be sure, we know only intensities or forms of energy that are already localized and distributed in extended space; intensity is inseparable from a process of extension that relates it to extended space and subordinates it to the qualities that fill space. But the corresponding tendency is no less true, since every extensity necessarily envelops or implicates within itself the intensity of which it is an effect. A “sign,” in its second aspect, is an intensity produced by the asymmetry of the differential relations, whereas a “quality” appears when an intensity reaches a given order of magnitude and these relations are organized in consciousness.22 Sensations thus present a double aspect: they necessarily refer to a virtual and implicated order of constitutive differences, but they tend to cancel out those differences in the extended order in which they are explicated. These intensive forces are never given in themselves; they cannot be grasped by the empirical senses, which only grasp intensity as already recovered or mediated by the quality that it creates. They can only be sensed from the point of view of the transcendental sensibility that apprehends it immediately in the encounter as the limit of sensibility itself. With the notion of intensity, Deleuze writes, “sensation ceases to be representative and becomes real.” Hence the formula: “intensity is both the unsensible and that which can only be sensed” (DR 230). What Maimon derives from this Leibnizian argument is a transcendental method of genesis rather than one of simple conditioning; a clear sensation emerges from obscurity by a genetic process, as it were through a series of filters, a series of successive integrations or syntheses. In the Critique of Pure Reason, Kant reserved the power of synthesis for the active “I think,” for the activity of the understanding, and conceived of the passive ego as a simple receptivity possessing no synthetic power. Because he considered the sensible to be a quality related to an object that sensibility intuited passively, he defined the transcendental form of space, as the condition of outer sense, by its geometric extension (pure intuition of objects or bodies). And if concepts in turn could be applied to intuitions, if a harmony was possible between the understanding and sensibility, it was only through the mysterious intermediary of the “schematism” of the imagination, which alone makes the spatio-temporal relations of intuition correspond to the logical relations of the concept. But the problem with the Kantian method of conditioning, as Maimon and Cohen were quick to point out, is that it leaves unexplained the purely external duality between the determinable (space as a pure given) and the determination (the concept as thought), invoking “hidden” harmonies between terms that remain external to one another.23 What the post-Kantians argued (as did Freud) is that the passive ego is itself constituted by a prodigious domain of unconscious and passive syntheses that precede and condition the activity of the “I think.” Beyond Kant's external method of conditioning, Maimon proposes an internal method of genesis in which the relation between the determinable and the determination is internalized in the Idea. Rather than perception presupposing an object capable of affecting us, and the conditions under which we would be capable of being affected, it is the reciprocal determination of differentials (dx/dy) that entails both the complete determination of the object as perception and the determinability of space-time as conditions: space-time ceases to be a pure given in order to become the totality or nexus of differential relations in the subject, and the object ceases to be an empirical given in order to become the product of these relations in conscious perception.
“Difference is not diversity,” writes Deleuze, “diversity is given, but difference is that by which the given is given, by which t
he given is given as diverse” (DR 222). The error of the dogmatic image of thought is not to deny diversity, but to tend to comprehend it only in terms of generalities or genera. One of Deleuze's philosophic aims is to show that the singularity and individuality of the diverse can only be comprehended from the viewpoint of difference itself. The Idea of sensation is constituted by two interrelated principles of difference: the differential relations between genetic elements, and the differences in intensity that actualize these relations. They do not indicate some sort of metaphysical reality beyond the senses; as Ideas they are posited in order to account for sensibility, though they are not given in experience as such. Whereas in Kant, Ideas are unifying, totalizing, and transcendent, in Deleuze, they are differential, genetic, and immanent. It is the series of filters, for example, that accounts for what Nietzsche called the faculty of forgetting, or Bergson's claim that perception is necessarily eliminative and subtractive; subjectivity is (rather than simply has) an incomplete, prejudiced, and partial perception.24 Conversely, the significance of sensory distortions, such as those achieved in pharmaco-dynamic experiences or physical experiences such as vertigo, is often to approach the intensive depth that is always implicated in the perception of extensity: a kind of “pedagogy of the senses,” says Deleuze, that forms an integral part of transcendentalism.25 Deleuze gives an account not only of “natural” perception, but also of experiences that are often classed as “pathological,” to which he assigns a positivity of their own. Indeed, in his commentary on Leibniz, Deleuze goes so far as to write that “every perception is hallucinatory because perception has no object,” since it refers exclusively to the psychical mechanism of differential relations among unconscious perceptions (FLB 93). This is why difference must be understood, not as an empirical fact or even as a scientific concept, but as a transcendental principle, as the sufficient reason of the sensible, as the being of the sensible.
Descartes had posited the “clear and distinct” as the highest principle of common sense, a principle that would be prolonged in various forms in the post-Kantian tradition extending through Fichte and Hegel: the finite mind finds its point of departure in a confused and obscure understanding of the world, and reason constitutes a universal progress towards the clear and distinct, “the light which renders thought possible in the common exercise of the faculties.”26 In the lesser-known figures of Maimon and Cohen, Deleuze finds a “minor” post-Kantian tradition leading indirectly to Bergson and Nietzsche: a clear idea is in itself confused, and is confused in so far as it is clear. The conscious perception of the noise of the sea, for example, is clear but confused, for our perception comprehends the whole confusedly, and only expresses clearly certain elements and relations depending on the threshold of consciousness determined by our body. Conversely, the components of the Idea are distinct but obscure: distinct, in so far as all the drops of water remain distinct as the genetic elements of perception, with their differential relations, the variations of these relations, and the singular points they determine; but obscure, in so far as they are not yet “distinguished” or actualized in a conscious perception. Every sensation, in short, is clear but confused, but is constantly plunged back into the distinct-obscurity from which it emerged. In Deleuze, the principle of the clear and distinct is broken down into two irreducible values that can never be reunited to constitute a natural light.
Deleuze's theory of sensibility, in sum, is opposed to Kant's on these three interrelated points: the element of sensation must be found in the sign and not the qualities of a recognizable object; the sign is the limit-object of the faculty of sensibility, beyond the postulates of recognition and common sense; the Idea of sensibility is constituted by differential relations and differences in intensity, which give a genetic account of thought and constitute the conditions of real, and not merely possible, experience, since the conditions are never larger than what they condition.
THE THEORY OF ART: “PURE BEINGS OF SENSATION”
1. Philosophy and Art. With this rather summary sketch of Deleuze's theory of sensation in hand, we are now in a position to determine its relation to the theory of art. If Deleuze's many writings on art constitute an integral part of his philosophy, it is because works of art are themselves explorations of this transcendental realm of sensibility. The most general aim of art, according to Deleuze, is to produce a sensation, to create a “pure being of sensation,” a sign (WP 167). The work of art is, as it were, a “machine” or “apparatus” that utilizes these passive syntheses of sensation to produce effects of its own. The genetic principles of sensation are thus at the same time the principles of composition of the work of art; and conversely, it is the structure of the work of art that reveals these conditions. Deleuze has consequently developed his “logic” of sensation through a creative interaction with the various arts. In What is Philosophy? Deleuze defines philosophy as a practice of concepts, a discipline that consists in the formation, invention, or creation of concepts. “One can very easily think without concepts,” he writes, “but as soon as there is a concept, there is truly philosophy” (WP 32). Art is itself a creative enterprise of thought, but one whose object is to create sensible assemblages—or affects—rather than concepts. Great artists are also great thinkers, but they think in terms of sensations rather than concepts. Painters, for example, think in terms of lines and colors, musicians think in sounds, film-makers think in images, and so on. Neither discipline has any privilege over the other; to create a concept is neither more difficult nor more abstract than creating new visual or audible combinations; and conversely, it is no easier to read an image than it is to comprehend a concept.
As a philosopher, Deleuze's aim in his studies of the arts is to create the concepts that correspond to these sensible aggregates. Francis Bacon: The Logic of Sensation creates a series of philosophic concepts, each of which relates to a particular aspect of Bacon's paintings. The text is organized in a quasi-musical fashion, divided into seventeen sequences or series that develop local concepts as if they were melodic lines, which in turn are made to enter into increasingly complex contrapuntal relations, and which together form a kind of conceptual composition that parallels Bacon's sensible compositions. Similarly, Deleuze describes his two-volume Cinema as “a book of logic, a logic of the cinema” that sets out “to isolate certain cinemato-graphic concepts,” concepts that are proper to the cinema, but which can only be formed philosophically (N 47, MI ix). The same must be said for Deleuze's essays in music, literature, and the theater, notably those collected in Essays Critical and Clinical.
Modern art and modern philosophy converged on a similar problem: both renounced the domain of representation and instead took the conditions of representation as their object. Paul Klee's famous phrase echoes through Deleuze's writings on the arts like a kind of motif: not to render the visible, but to render visible.27 Much of twentieth-century painting aimed, not at the reproduction of visible forms, but at the presentation of the non-visible forces that act behind or beneath these forms. It attempted to extract from these intensive forces “a block of sensation,” to produce a material capable of “capturing” these forces in a sensation. When pious critics reproached Millet for painting peasants who were carrying an offertory like a sack of potatoes, Millet responded by saying that what matters in the painting is not what the peasant is carrying, but rather the exact weight common to the two objects; his aim was to render the force of that weight visible in the painting. In the paintings of Cézanne, who gave this notion of force its first full expression, mountains are made to exist uniquely through the geological forces of folding they harness, landscapes through their thermal and magnetic forces, apples through the forces of germination. Van Gogh even invented unknown forces, such as the extraordinary force of a sunflower (FB 49). Proust discovered that what the worlds of signs render visible is nothing other than the various invisible structures of time (passing time, wasted time, time regained).28 Modern music has perhaps confronted this probl
em most directly, trying to develop a highly complex and elaborate material capable of making the non-sonorous forces of time audible, a material that could render duration sonorous, as in the rise of timbre in Stravinsky and Boulez, Edgar Varese's ionization of sound, or John Cage's experiments in noise such as the prepared piano.29
