Full Idea
Sameness of parts is not sufficient for identity of artefacts at a world, since the very same parts may turn up at different times as the parts of artefacts with different designs and functions.
Gist of Idea
Same parts does not ensure same artefact, if those parts could constitute a different artefact
Source
Graeme Forbes (The Metaphysics of Modality [1985], 7.2)
Book Reference
Forbes,Graeme: 'The Metaphysics of Modality' [OUP 1985], p.168
A Reaction
Thus the Ship of Theseus could be dismantled and turned into a barn (as happened with the 'Mayflower'). They could then be reconstituted as the ship, which would then have two beginnings (as Chris Hughes has pointed out).