- ---- by Bruce BaughDeleuze's most interesting thoughts on theory come in a discussion with Michel Foucault, where he puts forward the following idea: 'A theory is exactly like a box of tools . . . It must be useful. It must function' (D&F 1977: 208). A theory is something that we must construct as a response to a problem, and if it ceases to be useful, then 'we have no choice but to construct others'. This approach to theory is inherently practical, although Deleuze distinguishes between theoretical and practical activity, while at the same time arguing that theory is neither a foundation for practices that would merely apply universal theories to particular cases, nor the result of a reﬂection on particular practices that extract universal norms from particular cases. Rather than being universal, a 'theory is always local and related to a limited field'. Extending theory to practice is not merely the application of universal rules or theorems to particular cases, but a 'relay' to a 'more or less distant field of practice' in response to 'obstacles, walls and blockages' within the theory's own immanent domain. By 'relaying' to practice as 'another type of discourse' with a different domain, theory uses practice as a way of overcoming its internal difficulties, making practice serve as 'a set of relays between one theoretical point and another' (D&F 1977: 206). Conversely, theory can serve as a relay from one practice to another, connecting one practical field to a different one in order to overcome a practical impasse. In the latter case, theory does not represent or 'speak for' practice, any more than practice 'applies' theory: 'there's only action - theoretical and practical action' connected in networks and relays. As an example, Deleuze refers to his and Foucault's work with prisoners as a way of connecting 'official discourses of confinement' to the discourse of the confined themselves, a move that is simultaneously theoretical and practical. As Foucault puts it in the same dialogue, 'Theory does not express, translate, or serve to apply practice: it is practice' (D&F 1977: 208).Nowhere else does Deleuze offer such a positive appreciation of theory, which he usually downgrades in contrast with thought: 'Thinking's never just a theoretical matter. It has to do with vital problems' (D 1995: 105). Yet thought shares many characteristics with what he said about 'theory' in the dialogue with Foucault. Thought is a practical activity, work; philosophy, specifically, is thought-experimentation through the creation of concepts, each concept being a response to a problem whose conditions and scope the concept helps define, and each concept being created in the midst of already existing concepts which encounter impasses or blockages that require new concepts as 'bridges or crossroads' enabling them to join up with other concepts responding to problems subject to the same conditions (D&G 1994: 27). 'A concept lacks meaning to the extent that it is not connected to other concepts and is not linked to a problem that it resolves or helps resolve' (D&G 1994: 79). Problems necessarily change along with the changing conditions of thought and action. Thought, then, is a strategy in the face of problems, and seeks solutions through creating concepts, ways of thinking, and a system of coordinates that dynamically relates thoughts and problems to one another. On this conception, the 'practice' that serves as a relay between one theoretical point and another is thought itself, and the singular theoretical points are concepts in the case of philosophy, affects and percepts in the case of art, and functions in the case of science.Deleuze's pragmatic conception of theory also extends to his explanation of Foucault's distinction between the 'classic' intellectual, who 'could lay claim to universality' in virtue of the writer's social position being on a par with jurists and lawyers who represent the universality of law, and the 'specific intellectual' who 'tends to move from one specific place or point to another', 'producing effects not of universality but of transversality, and functioning as an exchanger' between different theoretical fields, but in the context of practical and political struggles (D 1988b: 91). The specific intellectual's expertise or theory is always local, expressing a fragmentary totality that is necessarily limited and necessarily runs up against impasses or 'walls' that can be breached by a strategic relay or detour through other theoretical fields. No intellectual, and no theory, can totalise the entire field of knowledge and action. A theory multiplies and erupts in a totally different area by finding 'lateral affiliations and entire system of networks', or else it loses its efficacy (D&F 1977: 212). Transversal connections between theory and practice on the part of specific intellectuals would include nuclear physicists using their expertise to speak against nuclear weapons; a transversal relay from one theoretical domain to another would be Deleuze and Guattari's strategic shift of Friedrich Nietzsche from philosophy to ethnology in their own theoretical-political Anti-Oedipus (D&G 1983: 190-1).Connectives§ concepts
The Deleuze dictionary. Revised Edition Edited by Adrian Parr . 2010.