On July 13, 1924, Ernest Hemingway was on a balcony in Pamplona, Spain and saw a wounded main lying on the other side of the street. He became consumed with the feeling that he was that man, seeing himself in the near-dead Spaniard who had been attacked by bulls. "I am him," Hemingway later wrote. It was the very first time he wanted to be someone else, so he created the character of the adventurous writer. Notes on the Other follows the example of Hemingway's remarkable sensation in the form of...