Oliver Sacks, the man who could be considered the best writer among all neurologists, and vice versa, turned 80 on July 9, and presented his avid readers with a gift in the form of a short essay, published in The New York Times and entitled “The Joy of Old Age ‏(No Kidding‏)” ‏(July 6‏). It opened thus: “Last night I dreamed about mercury − huge, shining globules of...