Russellian Monism and Dispositional/Categorical Properties

{Note: this is a draft of some work that I might develop further with add'l research at some point. Comments or suggestions are welcome.}

I’m gratified that the position in Philosophy of Mind known as Russellian Monism (also known as Russellian theory of mind and probably the best developed account of neutral monism) has gotten more attention in recent years. However, the terminology typically used to describe the position today is different from Bertrand Russell’s, as presented in his 1927 work, The Analysis of Matter. This post discusses some of the issues involved, and briefly looks at how some stances in contemporary debates would fit with the original account.

In a recent post on the Brains blog, Richard Brown (referencing an online discussion he had with David Chalmers) said: “RM [Russellian Monism] is the view that the dispositional properties talked about by physics have as their categorical base phenomenal or protophenomenal properties.” While descriptions vary, the reference to dispositional and categorical properties is common. In his book, Ignorance and Imagination, Daniel Stoljar says the position is a combination of two theses. First: “…that physical theory tells us only about dispositional properties.” And: “The second thesis we need to consider is that the dispositional properties of physical objects do require categorical grounds; that is, for all dispositional properties, there must be a non-dispositional property... (p.110)”

Now, Russell never uses discusses properties at all, and certainly not dispositional or categorical properties specifically! These are terms which have emerged in the more recent debates of analytic philosophy. So, how well is the intent of RM captured when using this terminology? (Please again note I’m only speaking of Russell’s work in The Analysis of Matter).

Brief summary of RM

Russell’s project is to show how careful analysis of the formulation of physical theory can reveal a common framework connecting what we think of as the physical and mental realms. First, he argues that the subject matter of physics can be interpreted as an abstract description of events and their linkage in causal relations. He then argues that the mental realm can likewise be described in terms of events, and that given a causal theory of perception, we can view perceptual events (“percepts”) as connecting with physical events. And a key point is that our knowledge of the physical events (which is inferred and ultimately derived from observations) includes nothing which is known to be inconsistent with the mental.

Russell speaks of events (or groups of events) as having “intrinsic qualities” or “intrinsic character”. These are things which are known to be an aspect of percepts, but are not part of physics, given its abstract structure. He doesn’t assert that physical events must have qualities like those of percepts – he is agnostic -- but he argues there’s no reason they couldn’t.

One thing I would note before discussing the recasting of RM in terms of properties. Russell is very insistent on an event ontology, rather than one of objects or substance. This distinction is usually ignored in contemporary discussions of RM. I’ll assume for present purposes that an event can be seen as something which either bears properties or is itself a bundle of properties, in the manner of objects, although there may be some issues with this assumption.

Dispositional and Categorical Properties

The topic of the nature and roles of dispositional properties (or dispositions -- also known as powers) and categorical properties is complex, and there is an extensive literature that concerns many aspects of metaphysics. But it seems fairly clear why philosophers have connected these concepts to RM. Dispositional properties (roughly) are those that when possessed, like the classic examples of fragility or solubility, direct its bearer toward some manifestation. A categorical property is (roughly) something possessed by an object which need not be connected to such manifestations. Dispositions seem to be closely associated with  physical interactions and causation, while categorical properties appear to offer an affinity to “intrinsic qualities”.

So, if physical theories only describe occurences and causal relations (as in Russell), and these are due to dispositional properties, then dispositional properties are the content of physics. If categorical properties are intrinsic qualities (as in Russell), then these are properties which are not captured by formal physical theory; they are, on the other hand, things which we still might be acquainted with (in some fashion) via perception. At a minimum, they comprise a part of the world which could play a constituting role for mental phenomena.  So this sort of thinking likely gives rise to the typical contemporary description of RM we began with above.

Does this description of RM reintroduce dualism?

However, there are a number of nuances and controversies regarding the status of categorical and dispositional properties, and there might be danger that certain stances on these might lead to interpretations inconsistent with RM.  For instance, do categorical properties play a supporting role in causation as well, or not?  If the latter, does this lead to epiphenomenalism with regard to the mental?  If the former, what is the basis for ascribing such a role?  Cannot dispositions fully account for causes?  I’m not able to delve into all of the issues in detail. But I have one especially pointed concern: given Russell’s goal of monism, do we run the risk of re-introducing a variety of dualism in the form of these two sorts of properties.  If dispositions do the "physical" work in the ontology and categorical properties do the "mental" work, isn't this just a "property dualism" in the context of Philosophy of Mind?  With this concern in mind, I want to conclude by briefly looking at contemporary stances which seek to eliminate one of these property types, and see how they fit with the goals of RM.

1. Are dispositions fundamental, or are they reducible?

Some philosophers argue that dispositions are not fundamental and can be reduced to categorical properties.  For instance, there has been an extended debate over whether the ability to describe dispositions in terms of conditional statements means they are amenable to reduction.  David Lewis argued for such a reduction as part of his metaphysical program (sometimes called Humean superveniece). However, Lewis' theory effectively eliminated causation itself as a fundamental aspect of reality (it just reflects regularities in a static mosaic of qualities). There are other avenues to support real causation without dispositions, but for present purposes I conclude that, since Russell was working with an assumption of causal realism, "disposing of dispositions" wouldn't be appropriate as part of a property-based description of RM.

2. Alternatively, can we do without categorical properties?

The key issue here is “intrinsic qualities”. RM relies on the assumption that events have intrinsic qualities.  If you eliminate categorical properties – perhaps by assuming that dispositions are identical with their bases, or don’t need bases at all -- you might risk losing these qualities, which are traditionally associated with the categorical side of things.  Many philosophers have argued that a world of "bare" dispositions isn't coherent, and that they need a categorical base for support.  This is debatable.  But for present purposes, the issue is simply that a world of “bare” dispositions lacking qualities (and adequately described by physical theory, at least in principle) would not be consistent with RM.

 However, there is another option available for a "disposition-only" ontology.  Some philosophers, notably John Heil and C.B.Martin, identify qualities with dispositions (they are another aspect of the same property). This move retains consistency with RM. In fact this view might be a particularly good fit when combined with the notion that we only encounter the qualitative side of causation when in direct causal connection with something.  Perception detects this aspect, at least in some fashion, while the abstracting process of physics has no place for it.  Note, in constrast, that if we maintained the dual property picture, where qualities are distinct from dispositions, then the reasons for their being “on display” when we are in causal contact are less obvious.

So, given the aims of Russellian monism, the stance in modern debates over the role and nature of dispositional and categorical properties which offers the best fit is the Heil/Martin view -- sometimes described as an ontology of "powerful qualities".