In measured prose with a blessed lack of jargon, Sacks explores the ingenuity with which individuals cope with bizarre neurological conditions.
During a concert, a pianist finds a Mozart score "completely unintelligible". A detective writer discovers the text of his newspaper transformed into "Cyrillic one moment and Korean the next".
Sadly, people who overcome such complaints also suffer from the inevitable decay of age. After relating his own ailment ("Dr Sacks cannot recognise anyone," his personal assistant warns before a meeting.
"He can't even recognise his own building sometimes"), Sacks writes a frightening, funny diary (reminiscent of Woody Allen) about a melanoma found in his eye. Humane, empathic, he is the doctor you would want.