The temporal parts theorist avoids this worry as well.
According to the temporal parts theorist, the case of the statue and the clay is just like that.
According to the temporal parts theorist (or four-dimensionalist), persistence through time is exactly like that (see Quine 1953a, Lewis 1976, and Sider 2001).
The temporal parts theorist avoids this problem in the case of the statue and the lump, since he will say that those objects share some, but not all, of the same temporal parts.
The temporal parts theorist avoids this objection for he will say that, whenever Lump and David exist, there is a single object that exactly occupies the relevant location a temporal part that is shared by both David and Lump.
In this way, the temporal parts theorist finds a place for all of the objects introduced earlier, and thereby avoids an implausible correlation between the sortal terms of our language and the kinds of objects in the world.
The temporal parts theorist could follow the constitution theorist in claiming that the relevant objects differ in kind, for example, in virtue of their historical properties or he could simply insist that the difference in kind is grounded in the fact that the two objects have different temporal parts.
Typical temporal parts theorists argue that such indeterminacy results from a mismatch between human language and temporarily-coincident objects (of the sort discussed in section 4.1).
According to most temporal parts theorists, there are very many 'nested' four-dimensional objects involved in this process, some of which end before others do.
Vagueness, or indeterminacy, seems to be a feature of our everyday experience of persisting things, and it creates problems which, according to temporal parts theorists, can best be solved by accepting that things have temporal parts.
But unless temporal parts theorists are prepared to defend a doctrine of modally extended objects — objects extended through possible worlds analogous to objects extended in time, there remains a problem.
