Magical Abstractionism about Possible Worlds

In the third part of his magnificent work, On the Plurality of Worlds, David Lewis strives to argue against what he takes to be three seemingly possible versions of abstractionist accounts of possible worlds. As always, Lewis’s critical assessments are much clear and highly sophisticated. However, there are some complications in his discussion of the third kind of abstractionism, that is, what he calls the magical ersatzism. In this paper, I will attempt to clarify and defend Lewis’s objections against this third kind of abstractionism. As I will argue, the core of Lewis’s arguments against magical abstractionism (ersatzism) recognizes a sort of theoretical and methodological deficiency in such theories. Magical abstractionism does not fulfil our expectations about a sufficient account of possible worlds and modality. Unlike linguistic and pictorial abstractionism, magical abstractionism does not provide us with a clear and explanatorily sufficient account of how possible worlds represent the possibilities that we are inclined to accept. Magical abstractionists have a wrong conception of what is a sufficient metaphysical theory about modality. A true metaphysical theory about possible worlds must have something positive to say about the nature of the abstract entities that are going to play the metaphysical role of those possible worlds.