I introduce an argument for Platonism based on intra-mathematical explanation: the explanation of one mathematical fact by another. The argument is important for two reasons. First, if the argument succeeds then it provides a basis for Platonism that does not proceed via standard indispensability considerations. Second, if the argument fails it can only do so for one of three reasons: either because there are no intra-mathematical explanations, or because not all explanations are backed by dependence relations, or because some form (...) of noneism-the view according to which non-existent entities possess properties and stand in relations-is true. The argument thus forces a choice between nominalism without noneism, intra-mathematical explanation and a backing conception of explanation. You can have any two, but not all three. (shrink)

It is often assumed that theorizing in terms of natural properties is more objectively valuable than theorizing in terms of non-natural properties. But this assumption faces an explanatory challenge: explain the greater objective value of theorizing in terms of natural properties. In this paper, I answer that challenge by proposing and exploring three different accounts of the objective value of naturalness. Two appeal to constitutive natures: it is part of the constitutive nature of explanation, or of objective value, that theorizing (...) in terms of natural properties is more objectively valuable. The third appeals to the theoretical role that naturalness plays. (shrink)

Molinists hold that there are contingently true counterfactuals about what agents would do if put in specific circumstances, that God knows these prior to creation, and that God uses this knowledge in choosing how to create. In this essay we critique Molinism, arguing that if these theses were true, agents would not be free. Consider Eve’s sinning upon being tempted by a serpent. We argue that if Molinism is true, then there is some set of facts that fully explains both (...) Eve’s action and everything else Eve does that influences that action; and that if this is the case, Eve does not act freely. The first premise of this argument follows from the explanatory relations the Molinist is committed to, and the second premise follows from libertarian intuitions about free will. (shrink)

I show that centered propositions—also called de se propositions, and usually modeled as sets of centered worlds—pose a serious problem for various versions of Lewis's Principal Principle. The problem, put roughly, is that in scenarios like Elga's `Sleeping Beauty' case, those principles imply that rational agents ought to have obviously irrational credences. To solve the problem, I propose a centered version of the Principal Principle. My version allows centered propositions to be objectively chancy.

Social ontology is the study of the nature and properties of the social world. It is concerned with analyzing the various entities in the world that arise from social interaction. -/- A prominent topic in social ontology is the analysis of social groups. Do social groups exist at all? If so, what sorts of entities are they, and how are they created? Is a social group distinct from the collection of people who are its members, and if so, how is (...) it different? What sorts of properties do social groups have? Can they have beliefs or intentions? Can they perform actions? And if so, what does it take for a group to believe, intend, or act? -/- Other entities investigated in social ontology include money, corporations, institutions, property, social classes, races, genders, artifacts, artworks, language, and law. It is difficult to delineate a precise scope for the field (see section 2.1). In general, though, the entities explored in social ontology largely overlap with those that social scientists work on. A good deal of the work in social ontology takes place within the social sciences (see sections 5.1–5.8). -/- Social ontology also addresses more basic questions about the nature of the social world. One set of questions pertains to the constituents, or building blocks, of social things in general. For instance, some theories argue that social entities are built out of the psychological states of individual people, while others argue that they are built out of actions, and yet others that they are built out of practices. Still other theories deny that a distinction can even be made between the social and the non-social. -/- A different set of questions pertains to how social categories are constructed or set up. Are social categories and kinds produced by our attitudes? By our language? Are they produced by causal patterns? And is there just one way social categories are set up, or are there many varieties of social construction? -/- The term ‘social ontology’ has only come into wide currency in recent years, but the nature of the social has been a topic of inquiry since ancient Greece. As a whole, the field can be understood as a branch of metaphysics, the general inquiry into the nature of entities. (shrink)

In Molière’s comedy The Imaginary Invalid a doctor “explains” that opium reliably induces sleep because it has a “dormitive virtue.” Molière intended this to be a satirical play on the use of opaque scholastic concepts in medicine, and since then the phrase “dormitive virtue” has become a byword for explanatory failure. However, contemporary work on the metaphysics of grounding and dispositions appears to permit explanations with a strikingly similar structure. In this paper I explore competing verdicts on dormitive virtue explanation, (...) using a model of explanation I call Contextualist Pluralist Non-Realist Backing, or CPN Backing. I show that CPN Backing illuminates the puzzle about dormitive virtue explanation, shows what is required for a resolution, and makes sense of conflicting responses to this case. (shrink)