Daniel Nolan

One common style of objection to a metaphysical theory is to claim that even if the metaphysical posits of that theory were correct, they would not explain the phenomena they were posited to explain. This chapter compares an early example of this sort of objection—found in some of Aristotle’s criticisms of the theory of Forms—with a more recent one—found in discussions of the so-called ‘Unreasonable Effectiveness of Mathematics’. In both cases, it is hard to see how abstract objects, whether numbers or Forms, can help with our theorizing about concrete, particular, sensible objects. The chapter argues that there are important similarities in the answers available to defenders of the explanatory power of mathematics and Forms.

One of the standard approaches to the metaphysics of personal identity has some counter‐intuitive ethical consequences when combined with maximising consequentialism and a plausible (though not uncontroversial) doctrine about aggregation of consequences. This metaphysical doctrine is the so‐called ‘multiple occupancy’ approach to puzzles about fission and fusion. It gives rise to a new version of the ‘utility monster’ problem, particularly difficult problems about infinite utility, and a new version of a Parfit‐style ‘repugnant conclusion’. While the article focuses on maximising consequentialism for simplicity, the problems demonstrated apply more widely to a range of ethical views, especially flavours of consequentialism. This article demonstrates how these problems arise, and discusses a number of options available in the light of these problems for a consequentialist tempted by a multiple occupancy metaphysics.

Zoroastrianism is a religion with a long history, but it has been comparatively neglected by contemporary philosophers. This Element aims to bring aspects of its long intellectual history into conversation with contemporary Anglo-American philosophy. Section 1 provides an introduction to Zoroastrianism and its history, some of the important texts, and some contemporary philosophy engaged with Zoroastrian themes. Section 2 discusses distinctive contributions Zoroastrian thought can make to the problems of evil and suffering. And Section 3 discusses a 'quasi-universalist' approach to puzzles about heaven and salvation, inspired by Zoroastrian theological texts. This title is also available as Open Access on Cambridge Core.

The Stoics developed a fascinating and interlocking set of doctrines about time, and those doctrines stood in stark contrast to the theory developed by Aristotle and the Peripatetics. Some controversies about Stoic views of time centre on how to unpack their idea that time and the processes of the universe are cyclical. Other controversies concern their views of the nature of time, and its relationship to bodies: how are times divided, is there a present time, and are there any bodies that are found only in the past or only in the future, or are there only present bodies? This chapter will also suggest that some Stoics thought that some bodies are divided into temporal parts.

One important challenge in the ontology of institutions is re-identifying types of institutions across times and cultures. An exclusive focus on the most controversial cases can obscure some general issues about commonalities of institutions across cultures. To exhibit some of these general questions and to make some progress on them, this paper will focus on what will hopefully be a less hot-button institutional question: what is it for an organization to be a navy? While the variety of naval phenomena makes characterising navies a harder task than it might first appear, a functional account of navies with some additional conditions drawn from other approaches appears to provide the most fruitful line of investigation.

David Lewis's work is of fundamental importance in many areas of philosophical inquiry and there are few areas of Anglo-American philosophy where his impact has not been felt. Lewis's philosophy also has a rare unity: his views form a comprehensive philosophical system, answering a broad range of questions in metaphysics, philosophy of mind, philosophy of language, philosophy of action and many other areas. This breadth of Lewis's work, however, has meant that it is difficult to know where to start in Lewis's work and a casual reader may often miss some of the illuminating connections between apparently quite disparate pieces of Lewis's work. This book aims to make this body of work more accessible to a general philosophical readership, while also providing a unified overview of the many contributions Lewis has made to contemporary Anglo-American philosophy. The book can be divided into four parts. The first part examines Lewis's metaphysical picture - one of the areas where he has had the greatest impact and also the framework for the rest of his theories. The second section discusses Lewis's important contributions in the philosophy of mind, language and meaning. The third part explores some of Lewis's work in decision theory, metaethics and applied ethics, areas where his work in not necessarily as widely appreciated, but in which he has done a range of work that is both accessible and important. The final section focuses on Lewis's distinctive philosophical method, perhaps one of his most significant legacies, which combines naturalism with "common-sense" theorizing.

New Zeno cases are unfamiliar but not impossible, and reflection on these cases suggests they do not require exotic forms of causation or other unusual powers. Kaiserman and Magidor suggest that there is little to learn from reflection on these cases. It is argued that some of their own conclusions are important enough to count as valuable lessons. Hawthorne’s cases of social or legal causation via Zeno sequences merit careful attention. These cases may be nearer to reality than one might have thought: recipes are given for individual people with mundane powers to apparently bring about Hawthorne-style legal or social New Zeno cases. Perhaps what we should say about cases like those raised by Hawthorne is related to what we should say about putative cases where laws or social action putative bring about social inconsistencies.

What is the connection between valid inference and true conditionals? Many conditional logics require that when A is a logical consequence of B, "if B then A" is true. Taking counterlogical conditionals seriously leads to systems that permit counterexamples to that general rule. However, this leaves those of us who endorse non-trivial accounts of counterpossible conditionals to explain what the connection between conditionals and consequence is. The explanation of the connection also answers a common line of objection to non-trivial counterpossibles, which is based on a transition from valid arguments to the corresponding conditionals. It also contributes to the wider project of illuminating the connections between contexts of utterance, on the one hand, and the truth-conditions of conditionals uttered in those contexts, on the other.

Zurvanism was an ancient variant of Zoroastrianism. According to Zurvanism, the great powers of good and evil, Ahura Mazda and Angra Mainyu, were the sons of a greater god Zurvan, associated with time. According to Eudemus of Rhodes, some Persian thinkers, presumably Zurvanists, took there to be three great principles underlying the world: light, darkness, and greatest of all time (or perhaps, according to Eudemus, space). This paper explores what metaphysics might underlie these doctrines, and what contemporary options we have for making sense of a metaphysics where time is the ultimate principle. Among the options explored is the option that despite appearance many of the entities of the concrete world are identical to stretches of time, or are somehow aspects of stretches of time; that they include times as parts, or are included in times as parts; that they are somehow properties of time; or hylomorphic compounds of which time is the matter; that the world is somehow a mixture of time, light, and dark; or that somehow the ends or teloi of everyday objects and processes are to be found among good, evil, and time.

The ontological pictures underpinning David Lewis's Parts of Classes and On the Plurality of Worlds are in some tension. One tension concerns whether the sets and classes of Parts of Classes can be found in Lewis's modal space, since they cannot in general be parts of any possible world. The second is that the atoms that are the mathematical ontology of Parts of Classes seem to meet the criteria for being possible worlds themselves, and so fail to be the material Parts of Classes needs. Two different responses to these tensions are discussed: one is unappealing in several ways but keeps more of Lewis's doctrines, while the other requires some modifications to the system of Parts of Classes.

Williamson proposes that a "suppositional procedure" is a central heuristic we use to evaluate the truth of conditionals, though he also argues that this method often leads us astray. An alternative approach to the link between supposition and conditionals is to claim that we are guided by our antecedent conditional judgements in our supposing, and in particular in our determining which things follow from an initial supposition. This alternative explanation of the close link between conditionals and supposition is developed and compared to Williamson's proposal.

Thinking about metaphysical problems in terms of grounding has its uses, but those uses are limited. This paper argues against attempts to see issues of grounding as having a central and organising role in metaphysical inquiry. After arguing that grounding does some useful work, this paper will argue that grounding is neither the central tool for understanding explanation in metaphysics, nor defines the subject matter of metaphysics. Instead, grounding tracks only some of the metaphysical explanations we should be looking for, and is only one among many of the topics metaphysics aims to address.

This paper argues that all of the standard theories about the divisions of space and time can benefit from, and may need to rely on, parsimony considerations. More specifically, whether spacetime is discrete, gunky or pointy, there are wildly unparsimonious rivals to standard accounts that need to be resisted by proponents of those accounts, and only parsimony considerations offer a natural way of doing that resisting. Furthermore, quantitative parsimony considerations appear to be needed in many of these cases.

Thought experiments are common where infinitely many entities acting in concert give rise to strange results. A contemporary family of these thought experiments have been labeled “New Zeno” cases. These cases, however, can be generalized to ensure almost any outcome from systems with limited materials. Consider an infinite series of clowns, with iron wills and instantaneous balloon-placing powers. The chapter argues that, given New Zeno assumptions, as well as ensuring things like balloons appearing without any clown placing them, they can ensure the existence of mountains of ice cream or even the movement of galaxies. Reflection on these cases helps bring out what is so troubling about New Zeno cases, and raise again the specter that there is something impossible about actual physical infinites of this sort.

David Lewis rejected consequentialism in ethics. However, two aspects of his meta-ethical views make it a challenge to see how consequentialism could be resisted. Lewis endorses a maximising conception of rationality, where to be rational is to maximise value of a certain sort; he appears to think it is possible to be both rational and moral; and yet he rejects conceptions of moral action as acting to maximise moral value. The second tension in Lewis's views arises from his meta-ethics. Lewis's naturalisation of morality is in terms of a naturalised account of value, including moral value. Insofar as he offers a motivational story for moral judgements, it is one that goes via a motivational connection to value. Yet his anti-consequentialism seems to commit him to rejecting a story of moral action entirely in terms of pursuit of moral value. In both cases there are things to be said about how to weave these strands of Lewis's thought together. After setting out these two apparent tensions in Lewis's thought about ethics, the paper discusses what a Lewisian could best say about these puzzles. Lewisians do have a number of plausible options for dealing with the first challenge. While there are things a Lewisian could attempt to extend Lewis's moral naturalism in a way that could deal with the second challenge, it is harder to see how to do this in a satisfying way. Attention then turns to what Lewis said in his letters on these topics: on that basis, perhaps Lewis was close to being an agent-relative consequentialist after all.

An overview of hyperintensionality is provided. Hyperintensional languages have expressions with meanings that are more fine-grained than necessary equivalence. That is, the expressions may necessarily co-apply and yet be distinct in meaning. Adequately accounting for theories cast in hyperintensional languages is important in the philosophy of language; the philosophy of mind; metaphysics; and elsewhere. This entry presents a number of areas in which hyperintensionality is important; a range of approaches to theorising about hyperintensional matters; and a range of debates that attention to hyperintensional constructions has generated.

Marriages come in a very wide variety: if the reports of anthropologists and historians are to be believed, an extraordinarily wide variety. This includes some of the more unusual forms, including marriage to the dead; to the gods; and even to plants. This does suggest that few proposed marriage relationships would require 'redefining marriage': but on the other hand, it makes giving a general theory of marriage challenging. So one issue we should face is how accepting we should be of the reports: to what extent reported 'marriages' really are marriages. This paper defends the view that almost all of these reported marriages are in fact marriages, and suggests some theoretical approaches that may be generous enough to account for this.

Abstract Impossible fictions have lessons to teach us about linguistic representation, about mental content and concepts, and about uses of conceivability in epistemology. An adequate theory of impossible fictions may require theories of meaning that can distinguish between different impossibilities; a theory of conceptual truth that allows us to make useful sense of a variety of conceptual falsehoods; and a theory of our understanding of necessity and possibility that permits impossibilities to be conceived. After discussing these questions, strategies for resisting the picture of impossible fictions presented here and in Part I are discussed. Perhaps apparently impossible fictions describe possibilities after all; or perhaps impossible fictions are all trivial; or perhaps some apparently intelligible impossible fictions are unintelligible after all.

Impossible fictions are valuable evidence both for a theory of fiction and for theories of meaning, mind and epistemology. This article focuses on what we can learn about fiction from reflecting on impossible fictions. First, different kinds of impossible fiction are considered, and the question of how much fiction is impossible is addressed. What impossible fiction contributes to our understanding of "truth in fiction" and the logic of fiction will be examined. Finally, our understanding of unreliable narrators and unreliable narration in fiction needs to accommodate stories that, on the face of it, cannot possibly be true.

David Lewis’s arguments against magical ersatzism are notoriously puzzling. Untangling different strands in those arguments is useful for bringing out what he thought was wrong with not just one style of theory about possible worlds, but with much of the contemporary metaphysics of abstract objects. After setting out what I take Lewis’s arguments to be and how best to resist them, I consider the application of those arguments to general theories of properties and relations. The constraints Lewis motivates turn out to yield an argument for concretism about possible individuals that is quite different from the better-known Lewisian arguments for that position. The discussion also touches on the puzzling question of whether things are the way they are because of the properties they have, or are the properties and relations the way they are because of the things that have them.