The weeks after Turing's death were the longest of Ed's life. He went through the motions. He taught his students at the tutorial college in South Kensington—he had picked up some tutoring work, mathematics for undergraduates who were struggling, a job that paid poorly and demanded little and that he kept because the routine of it was necessary, because getting out of the flat each day was necessary, because the alternative was sitting at his desk in Bloomsbury staring at the letter to the Home...