"In July 2013, Oliver Sacks turned eighty and wrote [a] ... piece in The New York Times about the prospect of old age and the freedom he envisioned for himself in binding together the thoughts and feelings of a lifetime. Eighteen months later, he was given a diagnosis of terminal cancer--which he announced publically in another piece in The New York Times. Gratitude is Sacks's meditation on why life [continued] to enthrall him even as he [faced] the...

Long before Oliver Sacks became a neurologist and one of our finest science writers, he was a small English boy fascinated by metals -- and also by chemical reactions, the louder and smellier the better. His curiosity was encouraged and abetted by brilliantly quirky relatives: Auntie Len, who taught him that the beauty of numbers can be found in the spiral face of a sunflower; Uncle Dave, who invited the boy to his light-bulb factory; and two older...