Title: Numerical and Mereological Indeterminacy.

Abstract:This talk has two aims, one negative and the other positive.  The negative aim is to argue against the possibility of numerical or mereological indeterminacy by showing how the arguments given by Sider and Lewis can be modified so as to be resistant to the objections that might reasonably be leveled against them.  However, these arguments presuppose a ‘localist’ conception of vagueness, under which the notion of a borderline case, or of determinate truth, is taken to be meaningful.  I have elsewhere proposed a globalist conception of vagueness (Fine [2020]), under which indeterminacy is essentially a global rather than a local phenomenon.  The positive aim is to argue for the possibility of numerical and mereological indeterminacy once the localist framework is given up in favor of a globalist framework.