Riddling questions date back to antiquity, the two most famous being the Sphinx's "What goes on four legs in the morning, two legs in the afternoon, and three legs in the evening?" (whose answer, "Man", is subjected to intense analysis in Terry Pratchett's Pyramids ) and Samson's riddle to the Philistines in the Bible: "Out of the eater came forth meat, and out of the strong came forth sweetness" (i.e., honey from bees nesting in a lion's carcase).
Anglo-Saxon riddles were assembled in the Exeter Book (circa 975-1000), and indeed the classic riddle resembles an Old English kenning – a poetic "cryptic clue" – rather than the pun-based riddles popularized in Victorian times. Some riddles are unfair: Rumpelstiltskin's demand for his own name was intended as unanswerable; Lewis Carroll's Mad Hatter in Alice's Adventures in Wonderland (1865) can offer no answer to his own "Why is a raven like a writing-desk?"; and in J R R Tolkien's The Hobbit (1937) Bilbo's celebrated "What have I got in my pocket?" is an accidental subversion of the genuine riddle-game which it concludes. But when the Master Doorkeeper in Ursula K Le Guin's A Wizard of Earthsea (1968) requires, like Rumpelstiltskin, to be told his own guarded True Name, this tough-seeming riddle is a subtler test: the name may be had freely, if the supplicant Wizard only thinks of asking for it. Poul Anderson sent up the riddle-game in Three Hearts and Three Lions (1961), whose hero foxes a formidable Giant with children's catch-question riddles; Susan Cooper's The Grey King (1975) has a Plot Coupon guarded by such riddling questions as "What is the shore that fears the sea?" (beech-wood, which is harmed by water); the Bridge of Death scene in Monty Python and the Holy Grail (1975) again spoofs the riddle-game; Patricia McKillip's The Riddle-Master of Hed (1976) and its successors pivot on unanswered riddles hiding deep secrets and Prophecies; Michael Swanwick's The Iron Dragon's Daughter (1993) makes riddle-game exchanges the scoreboard in a Technofantasy duel of electronic weaponry. Generally, any Guardian of the Threshold is likely to require the answer to a riddle. [DRL]