Deleuze’s book on Foucault contains one of the most complete statements of the idea of diagramming society, and doing so through history. Deleuze doesn’t mean a visual diagram as such, but a way of thinking which can be used to speak of power, organisation and subjectivation:
If there are many diagrammatic functions and even matters, it is because every diagram is a spatio-temporal multiplicity. But it is also because there are as many diagrams as there are social fields in history. When Foucault invokes the notion of diagram, it is in connection with our modern disciplinary societies, where power controls the whole field: if there is a model it is that of the ‘plague’, which cordons off the stricken town and regulates the smallest detail. But if we consider the ancient sovereign societies we can see that they also possess a diagram, even if it relates to different matters and functions: here too a force is exercised on other forces, but it is used to deduct rather than to combine and compose; to divide the masses rather than to isolate the detail; to exile rather than to seal off (its model is that of ‘leprosy’).
This is a different kind of diagram, a different machine, closer to theatre than to the factory; it involves different relations between forces. More importantly, it creates intermediary diagrams in which we shift from one society to another: for example, the Napoleonic diagram, where the disciplinary function merges with the sovereign function ‘at the point of junction of the monarchical ritual exercise of sovereignty and the hierarchical, permanent exercise of indefinite discipline’. This is because the diagram is highly unstable or fluid, continually churning up matter and functions in a way likely to create change.
Lastly, every diagram is intersocial and constantly evolving. It never functions in order to represent a persisting world but produces a new kind of reality, a model of truth. It is neither the subject of history, nor does it survey history. It makes history by unmaking preceding realities and significations, constituting hundreds of points of emergence or creativity, unexpected conjunctions or improbable continuums. It doubles history with a sense of continual evolution.
Every society has its diagrams. Foucault was careful to work on a well-determined series and never interested himself directly in so-called primitive societies. None the less they would be a particularly good example, perhaps too good. For far from being devoid of politics or history, they have a network of alliances which cannot be reduced to a hierarchical structure or to relations of exchange between filial groups. Alliances take place between small local groups, which constitute relations between forces (gift and counter-gift) and direct power. Here the diagram shows how it is different from structure in so far as the alliances weave a supple and transversal network that is perpendicular to vertical structure; define a practice, proceeding or strategy distinct from any single combination; and form an unstable physical system that is in perpetual disequilibrium instead of a closed, exchangist cycle (which accounts for Leach’s polemic with Levi-Strauss, or Pierre Bourdieu’s sociology of strategies).
Deleuze, Foucault, 2006, p30-31
Running through his description of how the diagram functions in Foucault’s work is an argument for the use of diagrams over other forms of analytical organisation, such as structure and hierarchy. The diagram is more unstable, showing how social form is emergent out of particular relations, and so on. This, and the assertion of diagrams as showing “force is exercised on other forces” reminds me of Michael Mann’s explanation of the flexible relations between his own four sources of social power (Ideological, Economic, Political, Military).
Deleuze doesn’t seek to itemise a list sources of power like Mann, and might well want to propose others of a more ‘tactical’ nature (rationalities, practices, materialities), or indeed reject the somewhat tectonic sense of their interplay in Mann (I guess he might question Mann’s notion of radical change being transcendental rather than immanent). Mann on the other hand doesn’t seek to state the nature of this flexible relation like Deleuze, instead leaving it as a space which the work of historical description can fill. We might even imagine that he might suggest that however much Deleuze’s diagram seeks to evade the rigid prescriptiveness of structure, it still prescribes a formal universal to social organisation, and that this is itself potentially misleading.
So what does Deleuze’s diagram in Foucault bring to analysis of society? The question must in part be to do with the sense of the intervention of the graphical into the textural. For example, when we speak of structures or organisation or hierarchies, we don’t necessarily think in terms of visual representations, the visual representation of the form isn’t inherent to the term. But for diagrams this is not the case. The visual, material form of the diagram is inherently part of it. Saying that a society is structured by its diagram is a bit like saying that a society is structured by a ‘picture’ or by a ‘text’. A diagram has its own specificity of course. Diagrams are made of lines, vectors, intersecting zones, boundaries. They are schematic instead of pictorial. But more than a picture or a text, a diagram has a relatively specific function: it is an explanatory tool, and this adds a strange reversal – that which explains the society is seen as structuring the society. This is not the same as saying that our understanding of a society structures the society, it has something more substantive to say than that – the discursive is bound into the diagram’s graphical form, it is both something that frames the society, and something that forms the society.