The Savage Detectives - pg. 551

In the first, the sheriff and one of his deputies take a prisoner from his cell and lead him far out into the country to kill him. The prisoner knows what's happening and is more or less resigned to his fate. It's a harsh winter, day is dawning, and prisoner and executioners alike are complaining of the cold in the desert. At a certain moment, though, the prisoner starts to laugh, and the sheriff says what the hell's so funny, has he forgotten that he's about to be killed and buried where no one can find him? has he lost his mind? And the prisoner says, and this is the punch line, that he's laughing because in a few minutes he won't be cold, but the lawmen will have to walk back.