In another in a series of excellent interviews with contemporary philosophers, 3:AM Magazine’s witty and well-informed Richard Marshall talks to analytic metaphysician Stephen Mumford. Mumford is an important and influential contributor to the current revival of interest in powers and dispositions as essential to understanding what science reveals to us about the natural world. The notion of a power or disposition is closely related to what the Scholastics called a potency, and Mumford cites Aristotle and Aquinas as predecessors of the sort of view he defends. Mumford’s notion of the “metaphysics of science” is also more or less identical to what modern Scholastic writers call the philosophy of nature. But Mumford’s interest is motivated by issues in philosophy of science and metaphysics rather than natural theology. The interview provides a useful basic, brief introduction to some of the issues that have arisen in the contemporary debate about powers. Some comments on the interview: Mumford cites Bertrand Russell as a great thinker from whom one can learn much even if one largely disagrees with him. I agree with that assessment (where Russell’s serious philosophical work was concerned, anyway -- his popular writings on religion, morals, politics, etc. are awful), and I wrote my doctoral dissertation in part on Russell. I would qualify some of the specific points Mumford makes, however. The early Russell famously rebelled against the neo-Hegelian monism that dominated British philosophy in the late 19thcentury, in favor of a metaphysics of radically discrete objects. He famously suggested that for Hegel the world is like a jelly -- one continuous blob, as it were -- whereas for Russell himself the world was like a bucket of shot, countless disconnected individual bits.
Mumford gives the impression that dispositionalism -- which affirms an interconnectedness between things insofar as dispositions tend toward their manifestations (e.g. brittleness tends toward breaking) -- entails a return to something like the monism Russell rejected. But I think that is not correct (and I’m not sure Mumford would actually take it that far). Instead of comparing the world to either jelly or buckshot, we might compare it to a museum full of paintings that represent each other from different points of view. The paintings are discrete objects (unlike the Hegelian jelly) but not radically independent (unlike Russell’s buckshot) insofar as they point beyond themselves to each other. The Aristotelian conception of the world, anyway -- which, in fairness, Mumford himself may not be entirely committed to -- is a middle ground between monism (whether Hegelian, Parmenidean, or what have you) and radical metaphysical individualism (whether Humean, Ockhamite, or whatever).
Mumford might not be entirely happy with the painting analogy, though, since he indicates that he disagrees with George Molnar’s idea that powers exhibit a kind of intentionality insofar as they are “directed toward” their manifestations, and he favors instead the notion of what he calls the “dispositional modality, between pure necessity and pure contingency.” Here (with qualifications) I would side with Molnar. I also am wary of Mumford’s rejection of the division of properties into categorical and dispositional, which seems to threaten to lead to a metaphysics of pure potency devoid of act, to use the Scholastic language. (These are issues I’ll be dealing with in some forthcoming work on causation.)
Mumford also unfavorably compares Wittgenstein to Russell. I agree with Mumford’s reservations about Wittgensteinian method, but I think that Wittgenstein is nevertheless of great significance for metaphysics(despite Wittgenstein’s own intentions!) insofar as his work constitutes a powerful critique of reductionism, scientism, and related notions. I would say that Wittgenstein’s position points in the direction of something like an Aristotelian conception of human nature, even if he would himself never have taken it in that direction.
These disagreements notwithstanding, Mumford is always interesting and the interview is well worth reading. Mumford makes some wise remarks about science, noting that “physics largely consists of a mathematical representation of reality: usually an artificial portion of reality in a model. Reality should not be mistaken for that mathematical representation. The world is not a number, nor an equation.” (This is a theme I have addressed many times, such as hereand here-- Mumford, who is a fan of comic books, might especially like the first of those posts.) The joke Marshall cites from the book Mumford co-wrote with Rani Lill Anjum nicely parodies the clueless scientism that permeates so much of contemporary intellectual life.