The 5 star ratings are very suprising to me. This is an informational manual on how the brain works and that's about as far as it goes. It provides different puzzles for you to do, but the puzzles are presented as a side note, are very complicated and are never explained as to why or how they got the answer. You have to crawl before you can walk, and this book assumes that you are already a marathon runner.It would be analagous to buying a book on how to build your biceps. The author explains how the biceps work and as a side note tells you to do a set of 10 curls with 100 pound dumbells in each hand, but the author never describes to you how to actually do the curls, assumes that your biceps can handle that much weight, and never gives you any exercises or explanations on how to work up to that level of training. The author is obviously well versed in the functions of the brain, but is an extremely poor mental muscle trainer and fails to realize that if someone was gifted enough to understand all of the mysterious and esoteric puzzles in his book, then they would not need to buy a book on how to build their mental muscle.