Compositional Vagueness in Material Objects

I recently attended a conference in Nottingham entitled 'New Directions in Metaphysics', hosted by the University of Nottingham. The venerable Dean Zimmerman was there, giving a talk on property dualism. His talk didn't excite me too much, but when he brought up the well-known problem of the vagueness of composition, it got me thinking again on these questions.

To refresh your memory, the problem of the vagueness of composition arises if we consider a reasonable definition of a material object - say, a human being. Suppose that a human being is defined as being that object that is composed of all of these material elements - say elements a1-an. This seems fairly straightforward, until we consider that it is very hard to, as it were, draw a line around those elements that compose us and those that do not. In fact, when we get a very detailed, close-up view of these elements, it becomes more and more obvious that there are many different elements that are just as entitled to be a part of an object as the ones that we at first chose to countenance. That is, there are many different sets of elements that are up to the task. Or consider another analogous problem: take all of the elements that one might say composes a particular human being (a1-an) and ask yourself whether or not it would be acceptable to define this human being by excluding merely one of these elements - say a3. Repeat and repeat the thought experiment until you reach absurdity.

This seems like a fairly important problem for defining material objects - for once the thought experiment is carried out, there seems to be an extremely large group of acceptable candidates, none of which seem to have any special claim to being the set that defines a particular material object.

An interesting response to this problem is the one given by Peter vanInwagen, who claims that the only material objects that exist are those that are biological - and they are individuated by being a particular group of elements all participating in the biological functioning of an object. Any of those fringe elements that made-up other candidates won't be acceptable then, as they are not aiding in the biological functioning of the object in question - they are, as it were, just idly floating about. Of course, a well known problem for this kind of view is that it entails that things like 'tables' and 'chairs' don't exist. It's a bullet that not many have particularly wanted to bite.

For my part, I think vanInwagen's response is on the right track in a certain respect, in that it individuates material objects using a certain dynamic criterion. It seems to me that the reason that the 'many candidate' problems all get started by assuming that the individuation of a material object must be a merely static - in the case of Lewisian examples, a particular set of elements. There is, of course, something to be said for wishing one's identity criterion remain stable - for instance, you don't want it to be the case that the identity criterion for a material object is constantly changing full stop. But the set-theoretic element identifications are inadequate, I think, because they fail to have any dynamic qualities at all.

I suppose the reason for this is mostly historical . Couple the fact that analytic philosophical methods have always wanted identity to be a stable, unchanging primitive fact with the further fact that the concepts of mathematics have always been considered the most unchanging facts and there's good reason to follow this kind of idea through. But it's hard for me to take any of this seriously in light of the current state of metaphysics, physics and the developments in quantum mechanics. As far as I can tell, all the evidence in quantum mechanical physics points towards defining physical objects as dynamical - the wavefunction is certainly, if anything at all, a dynamic representation of reality. If the wavefunction does represent something physical, it represents something that is not merely 'categorical', and certainly doesn't represent it as simply a set of particular elements; think here only of the fact of wave-particle duality! And metaphysics too, riding the crest of scientific discovery, is edging more and more towards an ontology of dispositions and propensities. So why should we be persuaded by thought experiments involving 'candidates' that are unchanging, static sets of elements?

There's every reason to believe that a better criterion of material object individuation can be given by something that is unchanging and yet has a dynamical aspect - perhaps dispositionally, via (Lorentz) invariant mass; cf. Leibniz, who once defined substance as 'a principle of action and passion'. Under this general criterion, we may define a material object by picking out its fundamental dispositional properties. This kind of analysis certainly has no concern for which elements 'belong' to to an object and which do not and makes the rival candidates of Lewis' thought experiments seem much less interesting.

It might still worry one that this kind of individuating technique leaves open the question of which elements of a set truly belong to a material object and which do not. But I'm not so sure that this is much of anything to truly be worried about. If a material object is defined by (and perhaps, is essentially) a set of fundamental dispositions, asking which material elements belong to it and which do not is not asking anything very interesting about it - unless, of course, one thinks that the contingencies of the moment-to-moment career of the object in question is of any real importance; it certainly isn't important for scientific inquiry at any rate.

Bare Particular and Particularly Bare Ontologies

I had a short conversation with Kevin Houser, a local philosophy graduate student, about conventionalism in matters of individuation. For some reason in the process of Kevin's studies, he ran into the question (which he apparently must have some answer for)of whether or not the world is, proverbially, 'carved at its joints'. In other words, do we, as cognizers, hoist our concepts upon the world, individuating it and picking out entities of our own accord, or do we find objects pre-individuated and merely form concepts to comprehend and categorize them?

Kevin seems to think that the former has intuitive pull to it - we divide the world into differing numerically distinct objects according perhaps to our physical capacities (our basic chemical composition, the way our ocular system is configured, etc.) or our particular interests - perhaps we wish to define objects as those spatio-temporal continuants which have a minimal amount of change over time, as Hirsch does.

Let me weigh in here. I think the view that the world is ontologically nothing in particular is rather ridiculous for the following reason: particulars being nothing in particular is absurd. The thought being that if it makes no sense to talk of objects that are nothing in particular and the world is made up of objects, it makes no sense to talk of a world that is nothing in particular. I think there are good reasons for thinking that objects must have a certain character without which they could not exist and so I think that there are good grounds for thinking, via generalization, that the world is that way as well.

There are a few common ways that one might initially object. One can make the principled denial that there simply are no ways that objects must be - or, anti-essentialism. Or, one might claim that the objects in the world have distinctive features such that they could not lack them and yet exist, but that these features are merely conceptual constraints which we impose upon them - or, conceptualism.

Let me take issue with the first of these, which I think sheds important light on the second. I think a rather simple way to go about the denial of anti-essentialism is to make it clear that objects have certain abilities. If one is a sortal-essentialist, for instance, one will take an object to have a set of abilities which are in accord with the sortal under which it falls. But notice that for an object to have an ability it must likewise have the proper 'vehicle' to acquire the ability - the octopus has the ability to live underwater and it is its physio-chemical make-up which is the vehicle for it having this ability. But notice also that no vehicle is had without it being able to have been had, since it is a necessary truth that if an object x has P, x is able to have P - or if P(x), then Possibly P(x). The point here is that, at ground floor, it cannot be the case that no object has any abilities necessarily, because the absence of some (basic) abilities will preclude the object from having any vehicles and/or abilities whatsoever. The suggestion being that the essence of an object is that which allows for any and all properties that it might possess.

Taking this as a rough argument against anti-essentialism, one might yet object: Sure, an object must have a certain feature that enables it to be anything at all, one that grounds it having any properties whatsoever, but we are the ones who give it such features by categorizing it under certain sortal terms. Here is how I would respond, ala Wiggins. It is true that we, as cognizers, conceptualize objects under certain sortals and make modal judgments based on their being so characterized. But, the modal principle remains - what is actual for an object is possible for an object. Why is this relevant to this question? Consider a pumpkin; it is, after all, that time of the year.

Suppose one carved out of a pumpkin a small square and held it in his hand declaring, "This object that I hold in my hand is defined purely by my own will - I decided upon its features, choosing ones which were relevant to my interests. The way this object is, since I have formed it, has nothing to do with the way the pumpkin is". What are we to say to this? I think the proper response is something like, "Look, you may have decided on the shape and the length and the breadth of this object, but you did not - and could not - decide on what it is, at root. Furthermore, the way this object is does say something about the way the pumpkin is - for one, that the pumpkin is such that it allows for you to form such an object from it."

The intuitive thought: even if it were the case that cognizers themselves decided upon the 'boundary' or individuating features of the everyday objects of experience, there are two things which no cognizer could, even in principle, decide upon: the limits - the possibility or contingency/necessity - of their being able to impose such categorizations of individuality and, consequently, whether or not the their decision reflects something about reality.