Word-puzzles and conundrums used since ancient times for many purposes, from amusing children and quickening the minds of scholars, to riddle contests settling disputes, even determining gruesome fates.

In The Hobbit, Gollum challenged Bilbo Baggins to a riddle-game, to decide whether he would let him go or kill and eat him. The contest became ever more sinister because, distantly sharing a common culture, they used riddles learned in innocent childhood, to determine a matter of life and death.

Tolkien will have known the Old English riddle collections and the Norse sagas. In one, the god Odin won a riddle-game by asking a question only he could answer. His opponent was honour-bound to accept defeat. Bilbo did likewise asking Gollum “What have I got in my pocket?”

Editor’s Note: Riddles are of great antiquity and feature in most cultures. Samson and Solomon ask riddles in the Old Testament, there were collections in Greece as early as 200BC and in more recent times they appear in operas (Turandot) and in fairy-tales, three riddles being the usual challenge for the hand of a princess.