The Ship of Theseus Is a Problem Without a Clean Answer

The Ship of Theseus asks: if you replace every plank of a ship one by one, is it still the same ship? And if someone collects the old planks and reassembles the original, which one is the real ship? This thought experiment cuts to the heart of identity and continuity — questions relevant to everything from cell regeneration to corporate mergers.

Source: Plutarch's Lives — Plutarch