Metaphysics, What?
Philosophers, I suppose, sometimes do metaphysics. No, let me put it more cautiously. Philosophers engage in certain practices, which they sometimes call "metaphysics". I can tell fairly well what sorts of practices will be labeled in this way -- e.g., much of David Lewis's work and the ensuing discussions, analytic philosophy of mind as driven by thought experiments, discussions of "personal identity". But is this really metaphysics? What the heck is metaphysics, anyway?
Here's one view. Let's call it the "mystical view" -- because really it is rather mystical, though many hard-nosed, atheistic philosophers seem implicitly (or even explicitly) to accept it. Metaphysics is the discovery, by a priori armchair reflection without depending upon anything empirical, of necessary truths of the universe -- truths such as that causes must precede effects, and that a functional duplicate of me must necessarily have (or will not necessarily have) conscious experience. Such facts are supposed hold true regardless of our concepts, to be independent of our (contingent) ways of thinking about things. We tap into them not by looking at the world but rather by... well, that's the mystical part. How, exactly, do we learn about the outside universe (not just our own minds) without looking at it? Those philosophers who have gamely tried to explain the process in question -- George Bealer and Laurence BonJour, for example -- have tied themselves in such knots, been forced to wave their hands at such absolutely crucial junctures, and if I may be frank have failed so utterly as to make the hopelessness of their project even more evident after having read them than one might have thought beforehand.
Here's another view of what's going on. Call this the "no metaphysics" view. What philosophers learn from their armchairs, without looking at the world, are facts not about remote possible worlds accessible in no other way, or facts about the deep metaphysical structure of the universe, but rather facts about their own minds -- facts, especially, about their concepts. What else would one learn about, sitting in one's armchair? We learn that our concept of "cause" is a concept involving the temporal priority of the cause to the effect, our concept of a person is thus-and-such, etc.
But of course learning about our concepts is learning not metaphysical truths in the sense that philosophers ordinarily mean the phrase but rather learning contingent empirical facts about how we think. The concepts so delivered may be revisable in the face of empirical evidence (see Friday's post). And furthermore, they are empirically, psychologically explorable: There's more than one way to learn about "our" concepts. Philosophers in the armchair might not be getting the story right, or they may be an unrepresentative sample.
The philosophical practices labelled "metaphysics", then, have two uses, as I see it, neither of which is the discovering of metaphysical truths: (1.) They provide a kind of evidence about how people (a certain type of people, with certain habits of reflection and standards of inquiry) happen to conceptualize things; and (2.) (more interestingly, to me) they provide recommendations about how we should conceptualize things. If construed in this way, such recommendations should be evaluated pragmatically, in terms of their usefulness in organizing our way of thinking about matters of concern to us.
Getting clear about the pragmatic standard of evaluation can, I think, help us sort through and evaluate competing "metaphysical" claims about personal identity, causation, and the like. So, for example, in my work on belief, which could easily be misconstrued as metaphysics, I advocate a broad dispositional approach as giving us the best tool for talking about and characterizing the kinds of case that interest me most in believing -- what I call the "in-between" cases of gradual learning and forgetting, self-deception, confusion, ambivalence, irrationality, and failure to think things through.