I find it surprising that this book is almost unknown and out of print. This collection of logic puzzles is easily one of the best ever written. Starting with a small set of lighthearted teasers, continuing with progressively more serious problems, including probably the most complete variations on liar/knight and metapuzzle themes, and finishing with the best amateur level introduction to "serious" mathematical logic I have ever seen. The ideas are presented with amazing clarity and in the form digestible to the most casual reader, preserving the beauty but without compromising the essence of the arguments. \nDon't let this one get away if you can find a copy.