This book is a defense of modal realism; the thesis that our world is but one of a plurality of worlds, and that the individuals that inhabit our world are only a few out of all the inhabitants of all the worlds. Lewis argues that the philosophical utility of modal realism is a good reason for believing that it is true.

On the most popular account of material constitution, it is common for a material object to coincide precisely with one or more other material objects, ones that are composed of just the same matter but differ from it in sort. I argue that there is nothing that could ground the alleged difference in sort and that the account must be rejected.

Various as these are, they have enough in common for them all to count as events, and in recent years philosophers have turned their attention to this..

In this study of events and their places in our language and thought, Bennett propounds and defends views about what kind of item an event is, how the language of events works, and about how these two themes are interrelated. He argues that most of the supposedly metaphysical literature is really about the semantics of their names, and that the true metaphysic of events--known by Leibniz and rediscovered by Kim--has not been universally accepted because it has been tarred with the (...) brush of a false semantic theory. (shrink)

This paper argues that a counterpart-theoretic treatment of events, combined with a counterfactual theory of causation, can help resolve three puzzles from the causation literature. First, CCT traces the apparent contextual shifts in our causal attributions to shifts in the counterpart relation which obtains in those contexts. Second, being sensitive to shifts in the counterpart relation can help diagnose what goes wrong in certain prominent examples where the transitivity of causation appears to fail. Third, CCT can help us resurrect the (...) much-maligned fragility response to the problems of late pre-emption by understanding fragility in counterpart-theoretic terms. Some reasons to prefer this CCT approach to rivals are discussed. (shrink)

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.

There is a well-known argument from Leibniz's Law for the view that coincident material things may be distinct. For given that they differ in their properties, then how can they be the same? However, many philosophers have suggested that this apparent difference in properties is the product of a linguistic illusion; there is just one thing out there, but different sorts or guises under which it may be described. I attempt to show that this ‘opacity’ defence has intolerable consequences for (...) the functioning of our language and that the original argument should therefore be allowed to stand. (shrink)

It is widely assumed that causation is an extensional relation: if c causes e and c = d, then d causes e. Similarly, if c causes e and e = f, then c causes f. Moving to the formal mode we have: The Extensionality Thesis (ET): (i) If „c causes e‟ is true and „c‟ and „d‟ co-refer, then „d causes e‟ is true; and (ii) If „c causes e‟ is true and „e‟ and „f‟ co-refer, then „c causes f‟ (...) is true. (shrink)