Rethinking Reductionism in Robert Boyle’s Time and Our Own

I offer two innovations that span from Robert Boyle’s time to now. I do this by clarifying and addressing an apparent tension in Boyle’s work that has surfaced with the recent enthusiasm for scholarship on Boyle’s philosophy of science. The tension is between a) the widely recognized reductionist parts of Boyle’s “corpuscular philosophy”, and b) his views on scientific explanation. My first innovation, concerning the history of Boyle’s own work, is to dissolve the tension by arguing for a novel interpretation of Boyle’s texts and experiments, according to which Boyle was not a father of reductionisms or even a reductionist as we have supposed. My second innovation, concerning the philosophy of present day reductionisms, is to argue that Boyle’s work should serve as a sophisticated model for bridging current impasses between reductionists and anti-reductionists. The most widely discussed of Boyle’s apparent reductionisms traces back to his views on the powers of physical bodies. For Boyle, powers are causal and relational qualities, distinct from the occult qualities the Schools recognized. A key’s power to cause a lock to open involves its shape being appropriately related to the lock’s shape. But many commentators maintain that Boyle thought these relational powers are fundamentally determined by, or ontologically reduce to, just the intrinsic properties of (features internal to) the bodies standing in the relevant relations. This is power intrinsicalism, which is indeed reductionist. Next consider Boyle on explanation. He held that excellent explanation requires citing what fundamentally determines the thing explained. And many of the actual explanations (of experimental observations) that he considered excellent appealed to not only intrinsic but also relational features among those determining the thing explained. Adding these together we get a view that is incompatible with power intrinsicalism. But we can and should read Boyle as embracing the relationalisms about explanation and avoiding the incompatible power intrinsicalism. I first show this in the context of his discussions of explanation, through novel analyses of his Torricellian experiments with mercury, and his famous dispute with Spinoza about how to explain the behavior of niter under manipulations. I next show how we can and should see Boyle avoiding power intrinsicalism in the context of his discussions of powers of bodies. Evidence comes from his famous lock-and-key passage, which I suggest entails absurdities about when locks and keys can have powers, unless read as avoiding power intrinsicalism. Evidence also comes from dissecting his discussions of corpuscles and their “mechanical affections”, e.g., their size, shape and mobility. Boyle probably thought these are all intrinsic properties of corpuscles. And he repeatedly insists these are essential to the fundamental determination of all physical phenomena. Authors have then inferred power intrinsicalism on Boyle’s behalf. But I document how Boyle carefully limits the essential role of mechanical affections to necessary rather than also sufficient for all such determination. Doing so completes my uncovering of the sophisticated senses in which still today we can, and I’ll argue should, be middle-ground mechanists, committing to neither intrinsicalist reductionism nor emergentist anti-reductionism.