As I have stated on this blog, and elsewhere, a materialist reading of Spinoza perhaps begins with EIIP7 and its related demonstrations and scholium. "The order and connection of ideas is the same as the order and connection of things." In place of hierarchy and causal impact Spinoza places ideas and things in a relation of identity and non-identity. How exactly to articulate this relation has lead to multiple interpretations. I would like to highlight three, Deleuze, Macherey, and Jaquet. The selection and order of authors reflects my own encounters and reading, the seemingly contingent order of nature, and not a necessary conceptual progression.
Deleuze dubbed his interpretation parallelism. Parallelism stresses first the univocity of things and ideas, seeing them both as expressions of the same substance. As Deleuze writes, "By his strict parallelism Spinoza refuses any analogy, any eminence, any kind of superiority of one series over another, and any ideal action that presupposes a preeminence: there is no more any superiority of soul over body, than of the attribute of Thought over that of Extension." Deleuze choice of parallelism as a term is unfortunate, as he seems to acknowledge. As much as it captures one side of the relation, that of difference, the fact that ideas determine ideas and bodies determine bodies, it effaces the other, that thought and extension, mind and body, are two different ways of grasping the same thing. Parallelism suggests that there are two things, two lines, when they are two different ways of viewing the same substance.
As is so often the case when it comes to Deleuze, what makes for bad Spinoza (or Nietzsche or Bergson) makes for good Deleuze. Deleuze's monstrous births eventually become part of the conceptual monster squad that is Deleuze, and Deleuze and Guattari's thought. Parallelism, or a variant of it, returns in A Thousand Plateaus, really the more Spinozist of the two volumes of Capitalism and Schizophrenia, Spinoza's things and ideas become "machinic assemblage of bodies" and "collective assemblage of enunciation." As Deleuze and Guattari write
On the first, horizontal, axis, an assemblage comprises two segments one of content and one of expression. On the one hand it is a machinic assemblage of bodies, of actions and passions, an intermingling of bodies reaction to one another, on the other hand it is a collective assemblage of enunciation, of acts and statements, of incorporeal transformations attributed to bodies. Then on a vertical axis, the assemblage has both territorial sides, or reterritorialized sides, which stabilize it, and cutting edges of deterritorialization which carry it away.
The order and connection is no longer that of substance, of God or nature, but of the processes of deterritorialization and reterritorialization in society. The order and connection is shifted from metaphysics, the order and nature of the universe, to politics---"politics precedes being." This shift is made possible by Marx, the mode of production as the order and connection of production and ideology, or more to the point, Foucault. As Deleuze argues with respect to Foucault the order of statements, discourse, and the assemblage of bodies, do not causally determine or refer to each other, but stem from the same relations of power. The shift of the terrain from the metaphysical to the political makes it possible for Deleuze (and Guattari) develop what was always at stake in parallelism, not just the univocity of being, but, more importantly, a relation between ideas and things, ideology (or discourse) and material forces, that is neither one of causality or expression. They are part of the same process of transformation.
Macherey offers a second interpretation, summed up by the phrase, causa seu ratio, cause or reason. What Macherey stresses is the that it is the order and connection that is the same, both ideas and things are subject to causal relations, to relations of cause and effect. Ideas and things, mind and bodies, have the same causal relations. The mind is a spiritual automaton just as the body is a relation of motion and rest, and just as it is possible to chart the causal connections between ideas as those between bodies. As Macherey writes,
Macherey's causa seu ratio can also be understood in terms of the larger post-Althusserian philosophical and political project. The idea of a causal relation between ideas, ideas determining and transforming other ideas, is a necessary axiom to such notions as "theoretical practice" and the idea that philosophy transforms the world by only acting on itself. It is not just Althusser, but any idea of philosophical transformation, that ideas can affect and determine other ideas, relies on some notion of a causal relation internal to thought. Spinoza (and Althusser) just tried to make this explicit, and philosophy has never forgiven them for it.
Chantal Jaquet offers a third possibility in Spinoza à l'Oeuvre: Composition des Corps at Force des Idées, what she calls the "logic of alternation." What she stresses is not the univocal difference of parallelism or the identity of causal relations, but the fact that ideas and things, bodies and minds, are two different ways of grasping the same thing. What matters is the transition from one to another. As Jaquet writes,
The logic of alternation does not postpone that of correspondence [of parallelism], but it has its own specificity which must be analyzed. The possibility of conceiving a thing, sometimes [tantôt] under the attribute of extension, and sometimes [tanôt] under the attribute thought, invites us to wonder about the reasons for the change of attribute and the passage from one to the other.
At the human level, it is a matter of grasping the moment when desires are seen as appetites and vice versa. "This logic of alternation is first of all a logic of reference." The same phenomena can be understood, or referred back to bodies or minds. Sleepwalkers remind us that the same actions that can be grasped according to the mind's power can be understood as the effect of the body. "The logic of alternation is not a logic of alternative." Sometimes, sometimes [tantôt, tanôt] is not either/or, it is not a simple arbitrary back and forth. There must be reasons, conditions, under which something is best grasped as thought or extention, minds and bodies.
Although the general rule is bodies determine bodies, and thoughts determine thoughts, there are moments when it is necessary to jump from one series to another. The most striking of such an alternation is in Spinoza's discussion of transcendentals and universals, confused ways of grasping the world. As Spinoza writes about transcendental concepts, "But when the images in the body are completely confused, the mind also will imagine all the bodies confusedly, without any distinction and comprehend them as if under one attribute, namely, under the attribute of being, Thing, and so forth." (EIIP40Schol) As similar process underlies universals, concepts such as man, horse, or dog, but in that case one striking characteristic is selected and retained, and man becomes a thinking animal, a featherless biped, etc.
Inadequate ideas can best be grasped through the composition of bodies. There are also points where the vicissitudes of affective life, the complex fears and jealousies, are best grasped through the connection of ideas in the mind rather than the intersections of bodies. The logic of alternation is a logic of the other scene. (It is possible to argue that Jaquet offers a better ground for the other scene than Balibar, but that is another post.)
Given what I stated above about Deleuze and Macherey it seems fitting to ask the question as to how this logic of alternation plays itself out as a social or political theory. I must confess that I have not finished Spinoza à l'Oeuvre yet so I do not know how this logic relates to Jaquet's idea of nonreproduction or transclasse. There is a chapter in the book dedicated to Jaquet's social theory. However, the structure of the book is what Jaquet calls, "pointillist," organized around several points of contestation and interpretation rather than offering a new reading of Spinoza. With that in mind I think one can provisionally state that the "logic of alternation" is an important addition to thinking through the intersection of bodies and minds, base and superstructure, material conditions and ideas. As Marx wrote, "The weapon of criticism cannot, of course, replace criticism of the weapon, material force must be overthrown by material force; but theory also becomes a material force as soon as it has gripped the masses." To which we can add sometimes material forces become ideas. This is another way of grasping what is called "capitalist realism": a set of social relations becomes an idea, an horizon of thought, through its sheer material force and presence. It is hard to think anything other than capital when that is all one lives and breathes.
The points where forces become idea and where ideas become forces must be mapped out. They are both the citadels and the fault lines of the ruling material and intellectual conditions.