On Tuesday I was browsing the 2 March 2012 Times Literary Supplement when I came across an article written by Daniel Dennett. In the essay, entitled “Sakes and Dints and Other Definitions that Philosophers Really Need Not Seek,” Dennett wonders about the ontological status of numbers, melodies, miles, electronic dollars, cahoots, smithereens, voices, haircuts, centers of gravity, minds — “the riotous assembly of candidate things” that humans deal with all the time. Should all of them be eliminated from material reality as mere epiphenomena, or should there be some robust ontology of objects that encompasses them all?
Ontology, it seems to me, has been resolutely reductive and minimalist in its attempts to come up with an exhaustive list of kingdoms, classes, genera and species of things. No doubt the motivation has been the right one: to prepare the dishevelled cornucopia for scientific accounting, with everything put ultimately in terms of atoms and the void, space-time points, or (by somewhat different reductive trajectories) substances and universals, events and properties and relations. As is well known, these Procrustean beds provide metaphysicians with no end of difficult challenges, trying to fit all the candidates into one austere collection of pigeonholes or another.
Take holes for example:
Our reliance on the concept of holes has a deep biological or ecological source, since holes are Gibsonian affordances par excellence, put to all manner of uses in the course of staying alive and well in a hostile world. Ubiquitous and familiar though they are, it is surprisingly hard to say what holes are made of, if anything, what their identity conditions are, whether they are concrete or abstract, how to count them, and so forth.
Dennett tentatively suggests regarding the hole as a meaningful category in naive physics but not in scientific physics.
But not so fast: holes may play a potent role in organizing the patterns studied in the special sciences — consider the importance of membranes and their multiple varieties of portals in cell biology, for instance — and what about the slit that figures so prominently in quantum physics?
Dennett regards the categorization of things as “more a matter of diplomacy than of philosophy.”
It is not that there is or must be — there might be — a univocal, all-in, metaphysical truth about what there is, but just better and worse ways of helping people move between different ontological frameworks, appreciating at least the main complexities of the failures of registration that are encountered.
The perspective I would recommend is that of the diplomatic anthropologist, not the metaphysician intent on limning the ultimate structure of reality. The ontology of everyday life is now teeming with items that sit rather awkwardly in the world of atoms and molecules. If we can understand how this population explosion came about, and why it is so valuable to us as agents in the world, we can perhaps discharge our philosophical obligations without ever answering the ultimate ontological question. To me it looks more and more like professional make-work, an artefact of our reasonable but ultimately optional desire for systematicity, rather than a deeper mystery in need of solving.