Abstract
According to Timothy Williamson, philosophy is not a mere conceptual investigation and does not involve a specific cognitive ability, different in nature from those involved in acquiring scientific or ordinary knowledge of the world. The author holds that Williamson does not succeed in explaining how it is possible for us to acquire, through thought experiments, the type of knowledge that, according to him, philosophy predominantly aims to acquire—namely, knowledge of metaphysical modality. More specifically, the author considers in detail Russell’s stopped clock and Locke’s prince and the cobbler thought experiments, and argues that Williamson has not shown how the kind of thought experiment of which they are instances, and which is typically encountered in philosophy, can be the instrument of knowledge of metaphysical modality that he takes this kind of thought experiment to be. More positively, the author advances that the modal conclusions of such thought experiments are drawn through conceptual investigation