There is order in the mathematical universe, but it can be hard to find. The orderly solutions to these abstruse, obscure, arcane, and delightful hairpullers run and hide in the bushes like rodents of the rainforest. Martin Gardner is one of the world`s preeminent creators of puzzles and the author of many books, including The Colossal Book of Mathematics (W.W. Norton, 2001) and Gardner`s Workout: Training the Mind and Entertaining the Spirit (A.K. Peters Ltd., 2001). Adapted from Martin Gardner`s column in Scientific American.