Every cell in your body changes, so why do you have a sense of continuity of the self – as though you're the same person you were a month ago? What does this have to do with the watercraft of the Greek demigod Theseus, or the End-of-History illusion, or why you go through so much trouble to make things comfortable for your future self, even though you don't know that person? And if there really were an afterlife, what age would your deity make everyone for living out their eternities? Join this week for a two-parter about the mysteries of selfhood.