Taking Possible Worlds Seriously

Abstract

The discussion so far has been employing the notion of possible worlds, popularized via the semantics of modal logic. How seriously, however, should possible worlds be taken? David Lewis held them to be genuine, concrete worlds, no less real than ours, the actual world, whereas Robert Stalnaker and Saul Kripke take them to be, rather, abstract entities, properties of the actual world—the only real world—which it might possibly possess. I agree with Lewis that possible worlds are no less real than the actual world, but I also agree with Stalnaker that only our world actually exists. I affirm that merely possible worlds, though they lack existence, possess being. I develop the notion of possible worlds, in which possible individuals exist, but also point to unsolved problems, such as how to account for the contingency of the actuality of the actual world.