“Inn-sewer-ants,” repeated Rincewind. “Tha’s a funny word. Wossit mean?” “Well, suppose you have a ship loaded with, say, gold bars. It might run into storms o

“Inn-sewer-ants,” repeated Rincewind. “Tha’s a funny word. Wossit mean?” “Well, suppose you have a ship loaded with, say, gold bars. It might run into storms or, or be taken by pirates. You don’t want that to happen, so you take out an inn-sewer-ants-polly-sea. I work out the odds against the cargo being lost, based on weather reports and piracy records for the last twenty years, then I add a bit, then you pay me some money based on those odds—“ Color of Magic, Terry Pratchett, page 45 That's the passage I found googling. It actually goes on and compares insurance and gambling. Highly recommended book (as is almost everything by the author of course)