This book proved to me that Feynman is truly an expert in his field. The book appears to be outdated in several areas, but this just proves to me that Feynman was on the cutting edge of science during his lifetime. Many of the questions he asked are currently solved, but some are still beyond reach.<br>Feynman is an excellent teacher that gets you thinking, and learning.<br>My only beef with the book has less to do with him and more to do with me. I utterly could not read or understand chapter four. For the most part, the rest of the book required little to no background in physics.