Abstract
The chapter takes structuralism to be the thesis that if F and G are alike causally, then F and G are the same property. It follows that our beliefs about the world can be true in various brain-in-a-vat scenarios, giving us refuge from skeptical arguments. The trouble is that structuralism doesn’t do justice to certain metaphysical aspects of property identity having to do with fundamentality, intrinsicality, and the unity of the world. A closely related point is that the relation…lies-at-some-spatial-distance-from…obeys necessary truths that need not apply to other relations with the same causal profile. This observation is especially important if, as David Lewis argued, the only alternatives to skepticism are structuralism and an anti-Humean stance toward modality. Some pertinent views of David Chalmers’s are discussed, and parallels are drawn between the structuralist response to skepticism and functionalism in the philosophy of mind.