Abstract

Wilson derives various broad philosophical morals from the scientific role played by the Principle of Virtual Work. He argues roughly that PVW conditionals cannot be understood in terms of things as large as possible worlds; that PVW conditionals are peculiar and so cannot be accommodated by general accounts of counterfactuals, thereby reflecting the piecemeal character of scientific practice and standing at odds with the one-size-fits-all approach of “analytic metaphysicians”; and that PVW counterfactuals are not made true partly by natural laws. I distinguish, elaborate and critically examine various arguments for these morals suggested by the PVW and Wilson’s text, looking especially at what makes a displacement “virtual” and the operation of the conditionals that the PVW takes to express necessary and sufficient conditions for equilibrium. Ultimately, I do not find the PVW to be especially well suited to support Wilson’s morals; some of these arguments fail, whereas others arise from general considerations rather than having to appeal to anything like the PVW.