I think the 2-star reviewer misses the point of this book: it's supposed to be fun. And it is. The puzzles are pretty challenging, and it definitely helps if you play chess. You tend to notice positional abnormalities that are the bases of the problems. From there, it's just detective work. But the real treat to this book is the world the author creates. Smullyan's characters can't play chess for nuts. You should see the bizarre positions they come up with - it's as though they're making random moves. Yet this doesn't diminish their love of the game one bit. They're such gentlemen too. No one minds when Dr. Holmes interrupts to ask questions. His new friends are always polite and like nothing more than a good demonstration of deductive reasoning. I wish I lived in their world.