Tycho Brahe was the greatest astronomer of his age: he had a metal nose (he'd lost the real one in a duel over mathematics), a pet elk that once got drunk and fell down the stairs, and twenty years of the most precise star measurements ever made. At a banquet in Prague he felt he needed to relieve himself, but it would have been rude to leave the table before the host. So he stayed. Eleven days later he died, perhaps from a bladder or kidney problem. On his deathbed he begged his young assistant Johannes Kepler to make sure his life had not been in vain. The words are imagined; we leave while the dinner is still going.