Classic from “Freaky Fables” by Handelsman (used to run in the British humor magazine Punch):
UTHER: Come out of there, Vortigern!
VORTIGERN: Shan’t! Who’s out there, anyway?
UTHER: Your worst enemy, King Uther!
VORTIGERN: How do you spell that?
UTHER: Who knows? W-Y-D-D-R, I shouldn’t wonder!