On Where Things Could Be

Some philosophers have replied to Leibniz’s “shift” argument against the reality of absolute space by appealing to anti-haecceitist doctrines about possible worlds, influenced especially by David Lewis’s counterpart theory. But separated from Lewis’s distinctive views about what possible worlds are, it is difficult to understand what those doctrines really amount to, and why they are relevant to the metaphysical issues at hand. In fact, the best way of making sense of the relevant kind of anti-haecceitism is one that really concedes the main point of the Leibnizian argument, pressing us to consider alternative metaphysical accounts of the world’s spatio-temporal structure.