As I concluded the previous post, I argued that the Deleuzian extension of Hume’s project entailed both the affirmation of monism (Spinoza) and multiplicity (Hume). This point is made crystal clear in A Thousand Plateaus when Deleuze and Guattari announce that “pluralism = monism” (ATP, p. 20; see this earlier post where I discuss this theme in the context of William James’ radical empiricism). This effort to bring Hume and Spinoza together, however, is fraught with difficulty, or at least apparently so, in a philosophical landscape that has been forever altered by Kant’s project.
But it is just this bringing together of Hume and Spinoza that a Deleuzian metaphysics accomplishes.
Since Kant was woken from his dogmatic slumber, Hume and Spinoza have come to be rethought in terms of a transcendental project that delimits the conditions for the possibility of experience and knowledge. A consequence of this shift is that Hume’s philosophy has largely come to be read as a project in epistemology (though of late there has been an effort to address metaphysical problems in Hume’s thought [see this post]). Hume, for example, comes to be seen as a precursor of a Bayesian epistemology whereby knowledge comes to be constituted through a process of induction that constitutes degrees of belief. Spinoza, at worst, is thrown into the refuse pile of philosophical dogmatists, one of the philosophers who accepted, without question, the metaphysical guarantees of our knowledge. Spinoza, in fact, goes much further than either Descartes and Leibniz in that while they accept God as the unquestioned guarantor of our knowledge of the world (Descartes) as well as the harmony of the world itself (Leibniz), for both of them God remains inaccessible and unknowable; Spinoza, by contrast, argues in the last half of Part 5 of the Ethics that even God can be known.
To state the contrast between Spinoza the dogmatist and Hume the skeptic, one could say that Spinoza presupposes the identity that grounds knowledge while Hume argues that this identity comes to be constituted. Husserl remarked upon this aspect of Hume’s thought, and it is for this reason that I have argued for a Humean phenomenology (see this). So how then can one bring Hume and Spinoza together? Put simply, through a rethinking of the principle of sufficient reason (PSR). And this brings me back to the issue that in part spawned the New Hume debate – to wit, Hume’s claim that the “particular powers, by which all natural operations are performed” are powers that provide the reason for the regularities of nature but these powers “never appear to the senses.” What are these powers? The simple answer to this question is that these are the laws of nature that are the subject of natural science, and it is precisely the nature of these powers that are revealed, over time, through the process of scientific enquiry. We could say that this is a scientific explanation of facts. That which appears to the senses, therefore, would bring in our mental faculties and the epistemological problem of how we come to know the “particular powers” of nature. With this we have an epistemological explanation, and from here we are not too far from the Bayesian epistemology mentioned above.
The problem with this simple answer is that it too presupposes the identity that guarantees the operations of representational thought (a subject for another post). To summarize Deleuze’s argument in a nutshell, representational thought is always mediated by identity and as a result it is never able to account for the constitution of the identity it always already presupposes. If one is to fully push the Humean project of accounting for the constitution of identity itself, therefore, then one will have to move beyond a representational account, and it is just here where we can find a rapprochement with Spinoza.
It is at this point where we need to rethink the PSR. To help in this process we can draw on a distinction Brian Weatherson makes between explanation and explication. Weatherson asks us to consider these three claims (see his post here):
- It’s raining in Seattle
- I’m wearing green socks
- It’s raining in Seattle and I’m wearing green socks
The first two claims can be explained by way of natural science – the first, Weatherson points out, “in terms of meterological facts about the Pacific Northwest” and the second “in terms of the state of [Weatherson’s] sock drawer and [his] sock preferences.” The third claim, however, cannot be given a similar explanation other than simply the conjunction of the explanations for 1 and 2. The fact expressed by 3 cannot be given, Weatherson argues, an explanation of the type given for 1 or 2, though the fact expressed by 3 is not inexplicable. It is perfectly explicable as the conjunction of other explanations.
We have at this point, I would argue, a version of the scientific and epistemological distinction we found in Hume. The unseen “particular powers” are the subject of a scientific explanation and the conjunction of separable perceptions or facts in the mind through habit become the subject of epistemological explanations. In Deleuze’s hands, he extends Hume’s project and argues that the “unseen” powers are unseen precisely because they are inexplicable. For Deleuze it is difference, or what he will also call disparity, that is “the sufficient reason of all phenomena, the condition of that which appears.” (DR 222). But when it comes to difference itself, Deleuze is quite clear that, “strictly speaking, difference should be ‘inexplicable’. Difference is explicated, but in systems in which it tends to be cancelled; this means only that difference is essentially implicated, that its being is implication. For difference to be explicated is to be cancelled or to dispel the inequality which constitutes it.” (DR 228). In other words, both the scientific and epistemological explanations, or explanations and explications, presuppose an already individuated identity; or, in Deleuze's terms, they presuppose difference as their sufficient reason.
As Deleuze will argue later in Difference and Repetition, it is multiplicity whose “being is implication,” or it is substance in the pre-Kantian sense of the term. Multiplicity “is the true substantive, substance itself” (DR 182). It is only when this substance or multiplicity is drawn into what Deleuze and later Deleuze and Guattari will call a “plane of consistency” that it then makes possible the processes of individuation that account for the constitution of identity itself. This substance, or multiplicity, is all there is – “Everything is a multiplicity..” (ibid) – and hence we have a rapprochement between a Humean argument whereby “multiplicity” is integral to the constitution of identity (this was a central argument of my Deleuze’s Hume, but see this and this) and Spinoza where the fundamental substance is absolutely infinite and without limits. As Ed Kazarian pointed out in a comment to my previous post, a metaphysics of multiplicity inspired by Simondon serves to bridge the gap between Humean multiplicity and Spinozist monism. It is this metaphysics that underlies the apparently enigmatic claim in A Thousand Plateaus that “pluralism = monism.” (p. 20).