_Possible Worlds_ presents the first up-to-date and comprehensive examination of one of the most important topics in metaphysics. John Divers considers the prevalent philosophical positions, including realism, antirealism and the work of important writers on possible worlds such as David Lewis, evaluating them in detail.

Counterfactuals is David Lewis' forceful presentation of and sustained argument for a particular view about propositions which express contrary to fact conditionals, including his famous defense of realism about possible worlds and his theory of laws of nature.

In this paper, we give a precise characterization of the principle of recombination and argue that it need not be subject to any restrictions.

Some argue that Lewisian realism fails as a reduction of modality because in order to meet some criterion of success the account needs to invoke primitive modality. I defend Lewisian realism against this charge; in the process, I hope to shed some light on the conditions of success for a reduction. In §1 I detail the resources the Lewisian modal realist needs. In §2 I argue against Lycan and Shalkowski’s charge that Lewis needs a modal notion of ‘world’ to ensure (...) that worlds correspond to possibilities. In §3 I respond to Divers and Melia’s objection that Lewis needs to invoke primitive modality to give a complete account of what worlds there are. In §4 I ask what it is for a notion to ‘involve’ modality. I conclude that the question is either in bad standing or at best offers little traction on the debate, and propose a different way of assessing when materials are appropriately included in a reductive base. (shrink)

In this paper, we give a precise characterization of the principle of recombination and argue that it need not be subject to any restrictions.

According to the Genuine Modal Realist, there is a plurality of possible worlds, each world nothing more than a maximally inter-related spatiotemporal sum. One advantage claimed for this position is that it offers us the resources to analyse, in a noncircular manner, the modal operators. In this paper, we argue that the prospects for such an analysis are poor. For the analysis of necessity as truth in all worlds to succeed it is not enough that no modal concepts be used (...) in the realist's account of a possible world (a fact we grant); rather, such an analysis will succeed only if the set of worlds that is postulated is complete. By appealing to plausible truths about the number of possible alien natural properties, we show that there are serious difficulties in guaranteeing that such a set exists without taking some modal concept as primitive. Accordingly, at least in its current form, Genuine Modal Realism must curtail its analytic ambitions. (shrink)

John Divers and Joseph Melia have argued that Lewis's modal realism is extensionally inadequate. This paper explains why their argument does not succeed.

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. (shrink)

In this reply, we defend our argument for the incompleteness of Genuine Modal Realism against Paseau's criticisms. Paseau claims that isomorphic set of worlds represent the same possibilities, but not only is this implausible, it is inimical to the target of our paper: Lewis's theory of possible worlds. We argue that neither Paseau's model-theoretic results nor his comparison to arithmetic carry over to GMR. We end by distinguishing two notions of incompleteness and urge that, for all that Paseau has said, (...) GMR remains incomplete in the relevant sense. (shrink)