"The most original, most profound, and most humorous collection of recreational logic and math problems ever written." — Martin Gardner, Scientific American "The value of the book lies in the wealth of ingenious puzzles. They afford amusement, vigorous exercise, and instruction." — Willard Van Orman Quine, The New York Times Book Review If you're intrigued by puzzles and paradoxes, these 200 mind-bending logic puzzles, riddles, and diversions will thrill you with challenges to your powers of reason and common sense. Raymond M. Smullyan — a celebrated mathematician, logician, magician, and author — presents a logical labyrinth of more than 200 increasingly complex problems. The puzzles delve into Gödel's undecidability theorem and other examples of the deepest paradoxes of logic and set theory. Detailed solutions follow each puzzle.