Forty-two years late — Oliver Sacks first published the “Hat” book in 1970, and has revised it four or five times since. Even so, some of the clinical tales he tells seem dated because we now know so much more about neurological problems than we did years ago. Sacks is a favorite author, brilliant, and writer on unusual and fascinating topics. Years ago his long New Yorker article on Tourrette’s syndrome and a surgeon and pilot who suffered from it was my introduction to this topic. A surgeon with Tourrette’s? How scary is that! Recently his long New Yorker article on musicophilia, being absolutely possessed by music, has been followed up with a book on that topic. One person developed the obsession after being struck by lightning–a rare accident causing an even rarer effect. In the “Hat” book, the last section on “retardates” is most interesting because it deals with savants like the twins who could almost instantly give with certainty the date of an event in the past or future 40,000 years. Sacks explains that the twins somehow intuited the algorithm that can produce that result. He also discusses the autistic genius child artist who, when taught to talk, lost her artistic ability. Beyond the interest of the factual case studies, Sacks raises more fundamental questions such as the meaning of being human when meaningful memory is gone and the conflict between normalcy and rare, unusual giftedness. I’m glad to have finally read this book, not to mention finding out that the title of the book comes from an actual circumstance.