Daniel Nolan

David Lewis’s work in the past few decades produced a powerful and thought-provoking system, and this collection of eleven essays represents state-of-the-art engagement with that system across a range of topics. The title would suggest that the papers would deal in particular with Lewis’s doctrine of Humean supervenience, the doctrine that all the contingent truths are ultimately determined by instantiations of fundamental categorical properties at points of space-time, and the spatiotemporal relationships between those instantiations: that everything in our world supervenes on “local, particular matters of fact.” It is a bold philosophical program, with a reductionist approach to our everyday theoretical commitments and a goal of explaining the connections between the mental and the physical, laws and regularities, causes and effects, and chances and their outcomes, all without “necessary connections between distinct existences.” It is a program that many philosophers believe deserves attention in detail, even if many would wish to dispute parts of the picture. Indeed, Lewis himself does not so much defend Humean supervenience outright as argue that it need not be given up on philosophical grounds —in principle the materials allowed by Lewis would be enough to enable the world to contain such things as minds, causation, people, and languages; and in principle, Lewis claims, his Humean world has everything needed for truths of counterfactual conditionals and statements of objective chances. Lewis leaves open the question of whether physics in fact delivers us such a sparse world, but he thought that the lessons of his in-principle defense of Humean supervenience would carry over to a system including whatever fundamental physical posits will be eventually settled upon by science.

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

In this paper, I take up three tasks in turn. The first is to set out what Routley thought we should demand of an all-purpose universal logic, and some of his reasons for those demands. The second is to sketch Routley's own response to those demands. The third is to explore how else we could satisfy some of the theoretical demands Routley identified, if we are not to follow him in endorsing Routleyan Ultralogic as a foundational logic. As part of this third project, I articulate what seems to me a preferable way of going to respond to the challenges Routley correctly identifies: and while I doubt what I will have to say would have convinced Routley himself, I will try to show that the approach I prefer has several advantages over Routley's.

This paper describes a plausible view of the nature of physical objects, their mereological connections to each other, and their relation to spacetime. As well as being parsimonious, the view provides a plausible context for denying all of the following: (1) A theory that objects endure through time (and do not have temporal parts, as normally conceived) cannot claim that material objects are identical to space-time regions they occupy. (2) At least one of the family of mereological connections (part-whole, overlap etc.) is to be taken as primitive. (3) Claims entirely in the language of quantifiers and identity and mereology are not semantically vague. It is thus an example showing that the there are more options for the metaphysics of objects, spacetime and mereology than many metaphysicians ordinarily assume.

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.

Lewis is famous as a contemporary philosophical system‐builder. The most obvious way his philosophy exhibited a system was in its content: Lewis's metaphysics provided answers to many metaphysical puzzles in an integrated way. In this chapter, the author offers some suggestions about how Lewis's own methodological stances can be improved. The chapter begins with “starting points”: places where Lewis looked for data for philosophical inquiries. This is followed by a section on one of the distinctive features of Lewis's technique of philosophical analysis: the project of specifying theoretical roles and then identifying deservers of those roles. This is one of the best‐known pieces of Lewisian method, despite an absence of any discussion of it in Lewis's 1983 remarks on method. The author also pays attention to the project of weighing costs and benefits, and philosophical theory‐selection in this way.