The Ship of Theseus is a thought experiment that questions whether an object that has had all of its pieces replaced remains fundamentally the same object. A king in Greek mythology and founder-hero of Athens, Theseus fought many naval battles. Athenians replaced the rotted oars of his ship over centuries to preserve it as a memorial. Plutarch made the puzzle famous in his Life of Theseus from the late first century. Other philosophers, including Plato, Heraclitus, Thomas Hobbes, and John Locke have also investigated the paradox.