Sparse Parts

Four dimensionalism, the thesis that persisting objects are four dimensional and thus extended in time as well as space, has become a serious contender as an account of persistence. While many four dimensionalists are mereological universalists, there are those who find mereological universalism both counterintuitive and ontologically profligate. It would be nice then, if there was a coherent and plausible version of four dimensionalism that was non-universalist in nature. I argue that unfortunately there is not. By its very nature four dimensionalism embraces theses about the nature of objects and their borders that make any version of non-universalist four dimensionalism either incoherent or at least highly implausible