I bought this book expecting an intermediate level treatment of groups. With intermediate, I'm not talking about formal proofs or anything, but at least the definition. When I opened the book for the first time, all I saw was blocks of text everywhere. I thought.. isn't this a maths book? Where is the math? In fact, the author makes an unbelievable effort to keep the book as light as possible, maybe to appeal to a wider audience. While I must admit the author did very well in explaining the concepts, and in writing an entertaining historical account of the classification of groups, when you finish reading this book, your understanding about the mathematics groups is unfortunately not much better than at the beginning. Everything, even the most simple things, seem to be beyond the scope of this book, so you end up knowing a lot about the history of 19th and 20th century algebra, but not much about groups. I must say, however, that the book is really entertaning from this point of view.