Typicality is routinely invoked in everyday contexts: bobcats are typically short-tailed; people are typically less than seven feet tall. Typicality is invoked in scientific contexts as well: typical gases expand; typical quantum systems exhibit probabilistic behaviour. And typicality facts like these support many explanations, both quotidian and scientific. But what is it for something to be typical? And how do typicality facts explain? In this paper, I propose a general theory of typicality. I analyse the notion of a typical property. (...) I provide a formalism for typicality explanations, and I give an account of why typicality explanations are explanatory. Along the way, I show how typicality facts explain a variety of phenomena, from everyday phenomena to the statistical mechanical behaviour of gases. Finally, I argue that typicality is not the same thing as probability. (shrink)

I show that standard grounding conditions contradict standard conditions for the identities of propositions.

I formulate a theory of groups based on pluralities and counterparts: roughly put, a group is a plurality of entities at a time. This theory comes with counterpart-theoretic semantics for modal and temporal sentences about groups. So this theory of groups is akin to the stage theory of material objects: both take the items they analyze to exist at a single time, and both use counterparts to satisfy certain conditions relating to the modal properties, temporal properties, and coincidence properties of (...) those items. (shrink)

This paper presents new data on the representation of women who publish in 25 top philosophy journals as ranked by the Philosophical Gourmet Report for the years 2004, 2014, and 2015. It also provides a new analysis of Schwitzgebel’s 1955–2015 journal data. The paper makes four points while providing an overview of the current state of women authors in philosophy. In all years and for all journals, the percentage of female authors was extremely low, in the range of 14–16%. The (...) percentage of women authors is less than the percentage of women faculty in different ranks and at different kinds of institutions. In addition, there is great variation across individual journals, and the discrepancy between women authors and women faculty appears to be different in different subfields. Interestingly, journals which do not practice anonymous review seem to have a higher percentage of women authors than journals which practice double anonymous or triple anonymous review. This paper also argues that we need more data on academic publishing to better understand whether this can explain why there are so few full-time female faculty in philosophy, since full-time hiring and tenuring practices presumably depend on a candidate’s academic publishing. (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.

I propose an account of probability in the Everett interpretation of quantum mechanics. According to the account, probabilities are objective chances of centered propositions. As I show, the account solves a number of problems concerning the role of probability in the Everett interpretation. It also challenges an implicit assumption, concerning the aim and scope of fundamental physical theories, that is made throughout the philosophy of physics literature.

In this paper, I give an argument for the view that non-fact entities – such as physical objects, abstract objects, events and so on – can ground other entities. Roughly put, the argument is as follows: those who accept this view can provide a more plausible account of the grounds of identity facts than those who deny this view.

According to the Best System Account of lawhood, laws of nature are theorems of the deductive systems that best balance simplicity and strength. In this paper, I advocate a different account of lawhood which is related, in spirit, to the BSA: according to my account, laws are theorems of deductive systems that best balance simplicity, strength, and also calculational tractability. I discuss two problems that the BSA faces, and I show that my account solves them. I also use my account (...) to illuminate the nomological character of special science laws. (shrink)

Explanations are backed by many different relations: causation, grounding, and arguably others too. But why are these different relations capable of backing explanations? In virtue of what are they explanatory? In this paper, I propose and defend a monistic account of explanation-backing relations. On my account, there is a single relation which backs all cases of explanation, and which explains why those other relations are explanation-backing.

I propose a `stage theory’ of groups: a group is a fusion of group-stages, where a group-stage is a plurality of individuals at a world and a time. The stage theory consists of existence conditions, identity conditions, and parthood conditions for groups.

I explore the relationship between a prominent analysis of intrinsic properties, due to Langton and Lewis, and the phenomenon of quantum entanglement. As I argue, the analysis faces a puzzle. The full analysis classifies certain properties of entangled particles as intrinsic. But when combined with an extremely plausible assumption about duplication, the main part of the analysis classifies those properties as non-intrinsic instead. I conclude that much of Lewis’s metaphysics is in trouble: Lewis based many of his metaphysical views—his thesis (...) of Humean supervenience, for instance, and his account of recombination—on an analysis of intrinsicality which does not sit well with quantum phenomena. (shrink)

Many explanations rely on identity facts. In this paper, I propose an account of how identity facts explain: roughly, the fact that A is identical to B explains another fact whenever that other fact depends, counterfactually, on A being identical to B. As I show, this account has many virtues. It avoids several problems facing accounts of explanatory identities, and when precisified using structural equations, it can be used to defend interventionist accounts of causation against an objection.

Philosophers have developed several detailed accounts of what makes some mathematical proofs explanatory. Significantly less attention has been paid, however, to what makes some proofs more explanatory than other proofs. That is problematic, since the reasons for thinking that some proofs explain are also reasons for thinking that some proofs are more explanatory than others. So in this paper, I develop an account of comparative explanation in mathematics. I propose a theory of the `at least as explanatory as' relation among (...) mathematical proofs. (shrink)

A popular method for comparing the structures of mathematical objects, which I call the ‘subset approach’, says that X has more structure than Y just in case X’s automorphisms form a proper subset of Y’s automorphisms. This approach is attractive, in part, because it seems to yield the right results in some comparisons of spacetime structure. But as I show, it yields the wrong results in a number of other cases. The problem is that the subset approach compares structure using (...) automorphism sets. So a different approach is needed: structure should be compared using automorphism groups. (shrink)

I propose a metaphysical theory of mechanisms based on the notion of causation. In particular, I use causation to formulate existence, identity, and parthood conditions for mechanisms. These conditions provide a sound metaphysical basis for accounts of mechanistic explanation, mechanistic organization, and for more restrictive theories of mechanisms.

I explore how the nature, scope, and limits of the knowledge obtained in orbital dynamics has changed in recent years. Innovations in the design of spacecraft trajectories, as well as in astronomy, have led to new logics of theory-testing—that is, new research methodologies—in orbital dynamics. These methodologies—which combine resonance overlap theories, numerical experiments, and the implementation of space missions—were developed in response to the discovery of chaotic dynamical systems in our solar system. In the past few decades, they have replaced (...) the methodology that dominated orbital research in the centuries following Newton's Principia. As a result, the kind of knowledge achieved by orbital research has changed: we can know how orbiting bodies in chaotic systems behave, but only over sufficiently short time scales; and we can reliably measure those temporal limitations, using Lyapunov time. (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)

A modal analysis of luck, due to Duncan Pritchard, has become quite popular in recent years. There are many reasons to like Pritchard’s analysis, but at least two compelling problems have been identified. So I propose an alternative analysis of luck based on the laws of statistical mechanics. The statistical analysis avoids the two problems facing Pritchard’s analysis, and it has many other attractive features.

If a proposition is typically true, given your evidence, then you should believe that proposition; or so I argue here. In particular, in this paper, I propose and defend a principle of rationality---call it the `Typical Principle'---which links rational belief to facts about what is typical. As I show, this principle avoids several problems that other, seemingly similar principles face. And as I show, in many cases, this principle implies the verdicts of the Principal Principle: so ultimately, the Typical Principle (...) may be the more fundamental of the two. (shrink)

According to Interventionism, explanations cite invariant relations which hold among multiple variables. Interventionism incorrectly implies, however, that many common scientific explanations—which cite single‐variable boundary constraints—are not actually explanatory. So I propose a different account of explanation, similar in spirit to Interventionism, which gets those cases of scientific explanation right.

I propose an account of possible worlds. According to the account, possible worlds are pluralities of sentences in an extremely large language. This account avoids a problem, relating to the total number of possible worlds, that other accounts face. And it has several additional benefits.

In this chapter, we explore some ways in which reasoning based on mysticism can be rational, focusing on the episode “The Fortuneteller,” in which Aang, Katara, and Sokka save a village from a volcanic eruption. Throughout this episode, Sokka advocates a purely empirical approach to reasoning. The villagers, however, believe that no source of knowledge is more reliable than Aunt Wu, the local fortuneteller. At several points in the episode, Sokka claims that the villagers’ reliance on Aunt Wu is irrational. (...) The villagers claim otherwise: since Aunt Wu has never led them astray, it is rational to rely on her. As we will see, the villagers are right. Their approach to reasoning – based on Aunt Wu’s fortunetelling – is more rational than it initially seems to be. Roughly put, despite their belief in the mystical, the villagers behave in accord with a standard philosophical theory of rational decision-making, a theory of what makes some decisions rational and other decisions not. So Sokka is wrong to claim that the villagers’ reliance on Aunt Wu is irrational. The villagers behave quite rationally. (shrink)

What sorts of aims, or goals, are constitutive of science? How does scientific evidence relate to the knowledge that science produces? And can the No Miracles Argument for scientific realism be defended against concerns about the explanatory capacity of truth? In Knowing Science, Bird engages with questions like these at length. In this paper, I engage with these questions too. I raise some concerns for the view that aiming at knowledge is constitutive of science. I provide three counterexamples to an (...) epistemic principle which Bird uses to argue for the view that evidence is knowledge. And I formulate a version of the No Miracles Argument which, by basing realism on a particular approach to meaning and to the empirical science of linguistics, avoids any mention of truth whatsoever. (shrink)

I present and explain the Bohmian account of collapse in quantum mechanics.

I derive a sufficient condition for a belief set to be representable by a probability function: if at least one comparative confidence ordering of a certain type satisfies Scott’s axiom, then the belief set used to induce that ordering is representable. This provides support for Kenny Easwaran’s project of analyzing doxastic states in terms of belief sets rather than credences.