Jonathan Schaffer

Properties come in clusters. It seems impossible, for instance, that a mass could float free, unattached to any other property. David Armstrong takes this as a reductio of the bundle theory and an argument for substrata, while Peter Simons and Arda Denkel reply by supplementing the bundle theory with accounts of property interdependencies. I argue against both views. Virtually all plausible ontologies turn out to be committed to the existence of free masses. I develop and defend the view that the clustering of properties is a mere contingent truth, on grounds that properties can be subtracted one‐by‐one. This opens the door not just to the (unsupplemented) bundle theory, but also to any plausible account of the relation between objects and properties.

How should one understand knowledge-wh ascriptions? That is, how should one understand claims such as ‘‘I know where the car is parked,’’ which feature an interrogative complement? The received view is that knowledge-wh reduces to knowledge that p, where p happens to be the answer to the question Q denoted by the wh-clause. I will argue that knowledge-wh includes the question—to know-wh is to know that p, as the answer to Q. I will then argue that knowledge-that includes a contextually implicit question. I will conclude that knowledge is a question-relative state. Knowing is knowing the answer, and whether one knows the answer depends (in part) on the question

Does what you know depend on what is at stake for you? That is, is the knowledge relation sensitive to the subject’s practical interests? Subject sensitive invariantists (Fantl and McGrath, 2002; Hawthorne, 2004, ch. 4; Stanley, forthcoming) say that the answer is yes. They claim to capture the contextualist data without the shifty semantics. I will argue that the answer is no. The knowledge relation is sensitive to what is in question for the attributor, rather than what is at stake for the subject. There is no substitute for the contextualist semantics.

Does G. E. Moore know that he has hands? Yes, says the dogmatist: Moore’s hands are right before his eyes. No, says the skeptic: for all Moore knows he could be a brain-in-a-vat. Yes and no, says the contrastivist: yes, Moore knows that he has hands rather than stumps; but no, Moore does not know that he has hands rather than vat-images of hands. The dogmatist and the skeptic suppose that knowledge is a binary, categorical relation: s knows that p. The contrastivist says that knowledge is a ternary, contrastive relation: s knows that p rather than q.

What knowledge is imperilled by sceptical doubt? That is, what range of beliefs may be called into doubt by sceptical nightmares like the Cartesian demon hypothesis? It is generally thought that demons have limited powers, perhaps only threatening a posteriori knowledge of the external world, but at any rate not threatening principles like the cogito. I will argue that there is a demon – the debasing demon – with unlimited powers, which threatens universal doubt. Rather than deceiving us with falsities, the debasing demon would allow us true beliefs, but only as guesses.

Feminist metaphysics is guided by the insight that gender is socially constructed, yet the metaphysics behind social construction remains obscure. Barnes and Mikkola charge that current metaphysical frameworks—including my grounding framework—are hostile to feminist metaphysics. I argue that not only is a grounding framework hospitable to feminist metaphysics, but also that a grounding framework can help shed light on the metaphysics behind social construction. By treating social construction claims as grounding claims, the feminist metaphysician and the social ontologist both gain a way to integrate social construction claims into a general metaphysics, while accounting for the inferential connections between social construction and attendant notions such as dependence and explanation. So I conclude that a grounding framework can be helpful for feminist metaphysics and social ontology.

Two of the assumptions that drive most contemporary philosophy of mind are the naturalistic thesis that minds, like mountains and molecules, are macro-objects in the natural order, involving nothing ‘spooky’, and a three-part taxonomy that recognizes substance dualism, property dualism, and monism as the available metaphysical options. Together, these assumptions drive most contemporary philosophers of mind to either monism of the materialistic stripe, or to a version of property dualism that treats mental properties on par with other macro-properties.

The argument from internal relatedness was one of the major nineteenth century neo-Hegelian arguments for monism. This argument has been misunderstood, and may even be sound. The argument, as I reconstruct it, proceeds in two stages: first, it is argued that all things are internally related in ways that render them interdependent; second, the substantial unity of the whole universe is inferred from the interdependence of all of its parts. The guiding idea behind the argument is that failure of free recombination is the modal signature of an integrated monistic cosmos. Frequently consider the connection of all things in the universe and their relation to one another. For in a manner all things are implicated with one another... (Marcus Aurelius, Meditations, p. 43)

Suppose that Ann says, “Keith knows that the bank will be open tomorrow.” Her audience may well agree. Her knowledge ascription may seem true. But now suppose that Ben—in a different context—also says “Keith knows that the bank will be open tomorrow.” His audience may well disagree. His knowledge ascription may seem false. Indeed, a number of philosophers have claimed that people’s intuitions about knowledge ascriptions are context sensitive, in the sense that the very same knowledge ascription can seem true in one conversational context but false in another. This purported fact about people’s intuitions serves as one of the main pieces of evidence for epistemic contextualism.

The physical and/or intrinsic connection approach to causation has become prominent in the recent literature, with Salmon, Dowe, Menzies, and Armstrong among its leading proponents. I show that there is a type of causation, causation by disconnection, with no physical or intrinsic connection between cause and effect. Only Hume-style conditions approaches and hybrid conditions-connections approaches appear to be able to handle causation by disconnection. Some Hume-style, extrinsic, absence-relating, necessary and/or sufficient condition component of the causal relation proves to be needed.

Kaplan (drawing on Montague and Prior, inter alia) made explicit the idea of world and time neutral propositions, which bear truth values only relative to world and time parameters. There was then a debate over the role of time. Temporalists sided with Kaplan in maintaining time neutral propositions with time relative truth values, while eternalists claimed that all propositions specify the needed time information and so bear the same truth value at all times. But there never was much of a parallel debate over the role of worlds. Let contingentism be the view (parallel to temporalism) that sides with Kaplan in maintaining world neutral propositions with world relative truth values, and let necessitarianism be the view (parallel to eternalism) that propositions specify the needed world information and so bear the same truth value at all worlds. This is the story of how the debate between the contingentists and the necessitarians might begin.