By most appearances, Turing had weathered the storm by the end of 1953. His probation and hormone treatments had ended.
Manchester University had agreed to employ him for at least five more years. That summer, Turing enjoyed a trip to two of his favor-ite vacation spots—Paris and Greece.
Turing had also begun to widen his horizons as a writer. He wrote a story about the struggles of a homosexual man, echoing many of his own experiences. In some ways, he seemed poised to enter the wider world of intellectual discourse, a world in which scientists and people in the humanities often seemed to be talking past one another.
There would seem to be time for anything that Turing really wanted to pursue. After all, he was barely in his forties. While many mathematicians feel that it is unlikely for people to do great work in that field in middle age, there was the new field of computer science that Turing had practically invented. Beyond that there was artifi-cial intelligence, filled with intriguing possibilities that Turing had already written about. There were also exciting discoveries on the frontiers of molecular biology, which was about to be revolutionized by the discovery of the role of DNA.
While traveling through Paris, Corfu, and Athens during the summer of 1953, Turing sent four postcards to his friend and col-league Robin Gandy. They included speculations and equations in quantum physics and an odd bit of poetry:
Hyperboloids of wondrous Light
Rolling for aye through Space and Time Harbour there Waves which somehow Might Play out God’s holy pantomime.
And then, abruptly, there was silence. On the morning of June 8, 1954, Turing’s housekeeper found his body in bed. On the nightstand was an apple with several bites out of it. The coroner ruled that Turing had committed suicide by cyanide poisoning.
Turing’s friends later remembered that he had been fond of the Walt Disney version of Snow White and the Seven Dwarfs, which he had seen in 1937. Turing often quoted these lines from the animated film:
Dip the apple in the brew
Let the sleeping death seep through
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Many of Turing’s colleagues did not believe the suicide verdict.
Turing seemed to have been in good spirits, talking about future projects and plans. No one could remember Turing speaking about the possibility of suicide, and he had left no note.
Turing’s mother, Sara, had a different theory about her son’s death. She believed it had been a tragic accident. She recalled how often he had engaged in messy chemical experiments, many involving cyanide. She also knew Turing liked to eat an apple before going to bed. Suppose he had gotten some cyanide on his hands, neglected to wash (not unusual), and ingested some cyanide while eating his apple?
Others did point to a few signs that Turing may have foreseen the end of his life. He had revised his will four months earlier. A few weeks earlier, he had visited a fortune-teller at a seaside resort.
When he emerged, he seemed shaken and uncommunicative.
Further, proponents of the suicide theory suggest that Turing had deliberately staged his death in such a way that it could be interpreted as an accident. This would allow his mother to take some comfort.
A third theory related to Turing’s wartime work, which was still classified top secret. After the war, it is possible that Turing had also engaged in code-breaking work related to the next great con-flict, that between Britain, the United States, and their allies and the Soviet Union. (If so, however, no details have every been revealed.)
When Turing was revealed as a homosexual, the British security establishment broke off all connections with him. But quite possibly they worried that he might be blackmailed or enticed into revealing the secrets of code breaking and technology that had played such an important part only a decade earlier. These concerns were likely heightened only months before Turing’s death, when a Soviet spy ring was uncovered at Cambridge. Two of its members, Guy Burgess (1911–63) and Donald Maclean (1913–83), had fled to the Soviet Union. Further, Burgess was a homosexual.
Today, more than 50 years later (and 20 years after the col-lapse of the Soviet Union), many secrets of the cold war have been revealed. However, if the shadowy world of spies and spymasters played a part in Turing’s death, those secrets remain undiscovered.
There may be an indirect connection between cold war paranoia and Turing’s death, however. During Turing’s last few years, the
anti-communist “witch hunts” spurred by the American senator Joseph McCarthy (1908–57) were in full swing. Besides suspected commu-nists, homosexuals were a major target of this activity, to be rooted out and fired from any job deemed “sensitive.” While Britain had nothing like the public uproar about the communist threat that had seized America, British intelligence officials were under intense pressure to accept security restrictions imposed by their American counterparts in exchange for access to nuclear secrets and other technology.
Thus, although there is no direct evidence, it is quite possible Turing’s sense of isolation and depression may have been fed by the realization that he might soon be prevented from traveling abroad, including the European trips that enabled him to enjoy thriving gay communities. Naturally a travel ban would also have prevented him from attending scientific and computing conferences as well.
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