cover image Satan, Cantor, and Infinity and Other Mind-Bogglin

Satan, Cantor, and Infinity and Other Mind-Bogglin

Raymond Smullyan. Alfred A. Knopf, $21 (0pp) ISBN 978-0-679-40688-4

In Smullyan's latest challenging collection of logic puzzles, the Sorcerer, a logician who uses logic so cleverly it seems like magic, visits an island where intelligent robots create other robots. King Zorn, Princess Annabelle, truth-telling knights and lying knaves lighten the presentation of puzzles as the Sorcerer explains the pioneering discoveries of mathematician Georg Cantor (1845-1918) who proved that there are different orders of infinity, and as he delves into paradoxes about probability, time and change. Smullyan ( The Lady or the Tiger? ) tosses in metapuzzles (which are solved on the basis of knowing that certain other puzzles can or cannot be solved) and explores self-referentiality, a property crucial to Kurt Godel's famous incompleteness theorem. The Sorcerer closes with a tale of how Satan is outwitted by a student of Cantor's. A mind-stretching entertainment for the serious, dedicated puzzle-solver. (Nov.)