This book quickly began at 5 stars for me, but dropped to three by the end. I did enjoy it, and I do recommend it, however.The author sets the book essentially as an epic quest to find, as the title suggests, the most extraordinary language learners. Really, we're speaking less of people who learn well, so much as people who learn many languages, followed by argument about how well these "Hyperpolyglots" learn, how deeply they learn, and to what end. As a person who enjoys language and the learning of new language, I was deeply interested in this book.Beginning with a case study of one historic polyglot, for what to me felt a little long, we eventually make our way to some other historic cases, then at last to some living examples. However, as the author comes into contact with brain researchers, and (IMO) hampered by his own admitted "positivism", here expressed by a need to use numerical data to squeeze meaning out of case study, we digress into a number of speculations about the functioning of the brain, accompanied by (in case the author is reading, I apologize quite sincerely, but it must be said) possibly the most awkward descriptive model of locations within the human brain, ever. I'm sure some people will be quite happy with it, but trying to picture hands upon a tilted inflatable globe of the world in order to picture where a discrete tissue structure isn't doing it for me. Consider including a picture of the brain, with labels in the back of the book, or perhaps just referencing some high-quality pictures on the book/author/publisher website we could consult for a future edition to accompany the globe idea. I ended up thinking about the scene in Chaplin's The Great Dictator where the Adenoid Hynkel character dances around with a globe-balloon. The book is at it's absolute strongest in the middle, where having finally moved on from the first figure, we find other stories, and then meet some living people. At this point, you're going to be hooked. At this point, the book has earned 5 stars from me.One star was lost simply through endless re-explanations of possible causality, accompanied by "cliff-hanger" style breaks in the text implying some amazing discovery or unbelievable event. I'm still not totally sure what jaw-dropping thing we were being lead to about Krebs' brain. Increased white matter someplace around Omaha, Nebraska or a pinkie around Gibraltar, I'll guess.But where the book bogs down, and thus losing the other star comes nearer the end, where contradictions begin to arise. While saying there's no connection between this and that, he suggests there are. While more or less suggesting non-polyglots have a dimwitted obsession with methodology, he continually returns to breathless descriptions of it for every case study, and even closes the book with a number of suggestion sections complete with italics. The book spends so much energy building it's own vocabulary of power words that by the end, you'll be reading sentences about neural tribes of hyperpolyglottery (should that be hyperpolyglotteracy though?) who promote brain plasticity through managed dopamine and executive function training. All in all, while I have loads of complaints with the book, I DID actually enjoy reading it, and if the subject matter resonates with you, you SHOULD read this book. Yes, I spent some time just now giving it and the author a hard time. A little less reliance on hard numbers (or MORE, proving something), and a few less literary "devices" (like the recapitulation-coda ending, cliffhangers, emotionally charged language where events don't warrant) and this would have easily been a 5 star book. I rarely give 5 stars, and I don't START at 5 for books, they have to earn them, and this book did just that. It just gave two away by the end is all.