all of which is the following. The Ship of Theseus This is a puzzle that has been around since antiquity, probably later than Heraclitus, but not much later. It first surfaces in print in Plutarch ( Vita Thesei , 22-23): ?The ship wherein Theseus and the youth of Athens returned had thirty oars, and was preserved by the Athenians down even to the time of Demetrius Phalereus, for they took away the old planks as they decayed, putting in new and stronger timber in their place, insomuch that this ship became a standing example among the philosophers, for the logical question of things that grow; one side holding that the ship remained the same, and the other contending that it was not the same.? Plutarch tells us that the ship was exhibited during the time [i.e., lifetime] of Demetrius Phalereus, which means ca. 350-280 BCE. (Demetrius was a well-known Athenian and a member of the Peripatetic school, i.e., a student of Aristotle. He wrote some 45 books, and was also a politician). The original puzzle is this: over the years, the Athenians replaced each plank in the original ship of Theseus as it decayed, thereby keeping it in good repair. Eventually, there was not a single plank left of the original ship. So, did the Athenians still have one and the same ship that used to belong to Theseus? But we can liven it up a bit by considering two different, somewhat modernized, versions. On both versions, the replacing of