Perdurantism, stage theory and ambiguity

In this thesis I defend a semantic claim about the persistence of material objects through time commonly termed perdurantism. I first motivate the shared metaphysical background, in particular the theses of eternalism and four-dimensionalism, shared by perdurantism and its competitors. I then argue that problems with counting and the predication of historical properties tell against stage theory, while unacceptable metaphysical commitments are fatal to the ambiguity theory. Perdurantism, on the other hand, can, by an appeal to counterpart theory of modality de re, answer the problem of permanently co-located entities.