Alan Turing was a computer scientist and cryptologist who made major contributions to the effort to defeat the Nazis in World War II. Many say that his efforts to break the German code shortened the war by 2 to 4 years. Turing is widely known as the father of modern computers for his work after the war in the design of machines and artificial intelligence before computers even existed. His life ended tragically in 1954 after he was prosecuted for being a homosexual and died of an apparent suicide. Because of his homosexuality and the secrecy of his code-breaking work, his pioneering accomplishments were not known to the world until just recently.
Alan Turing's life and accomplishments were recently brought forward to a lot of people by the release of the movie "The Imitation Game". While this movie does do the service of raising awareness of Turing's life, there were many liberties taken in the depiction of Turing and the other characters in the movie. Throughout this article I will try to clarify what is known about Turing's life and what was depicted in the movie for entertainment value.
Turing was born in Paddington, London in 1912. From an early age it was clear that Turing had a strong inclination towards mathematics and science, and his parents enrolled him in the Sherborne boarding school which was some distance away from London. Turing was not a model student at Sherborne, as his focus in scientific subjects did not meet the expectations of the headmaster. It was at Sherborne that he befriended fellow student Christopher Morcom who was a year ahead of him in school. During the years 1928 and 1929 Turing spent a great deal of time with his friend Christopher Morcom who challenged him intellectually. However, their friendship was tragically cut short when Morcom died of tuberculosis in February, 1930. It was the bond with Christopher and his memory that later inspired Turing to do great things.
After Sherborne, Turing went on to attend King's College in Cambridge. During his years as an undergraduate, Turing introduced to the world the concept of the "Turing Machine". He theorized that a machine could be built to carry out a method of instructions, or algorithm, and that it was possible to create a machine that could carry out an infinite number of such operations. In 1936 there were no computers or any types of machines that resembled computers, but Turing's writings showed that he envisioned these machines years before they were built.
Britain and the rest of Europe were embroiled in World War II in 1938, and Britain's war effort had an extremely difficult problem. The Nazis were sending encrypted messages using a machine called "Enigma" and the allies needed to break the code of Enigma to gain an advantage. The Enigma was a small machine that resembled a typewriter and could send messages understandable to other Enigma machines, but gibberish to anyone trying to intercept the messages. The formula for encryption was changed each day on the Enigma machines through a series of rotors on each machine, creating millions and millions of possible settings. Alan Turing was assigned to the team of codebreakers who would work at a top secret location in Bletchley Park, a large Victorian mansion about 50 miles north of London. No one knew of their activities, especially not the Germans who were confident that their code was unbreakable.
Turing and his team had as a starting point a machine that was put together by the Poles. The Poles had devised a machine called the "bomba kryptologiczna" and Turing put together a specification for a machine called the bombe, derived from the Polish machine. This machine would be able to rapidly attempt decryption of the messages with each rotor setting, and quickly eliminate the settings that proved impossible. By 1941 Turing's team had a good working model of the machine, but they were undermanned and could not build the machines fast enough to translate the messages. Requesting additional resources from the military chain of command did not work, so Turing took the unusual step of writing the Prime Minister Winston Churchill himself. Churchill, seeing the importance of the work to the war effort, ordered that the Bletchley Park team receive the resources they needed.
The work up until this point allowed the Bletchley Park team to crack reading some of the German communications, but the German Naval communications had additional complexity and proved to be more difficult to break. If messages from the German U-Boats could be cracked, it would turn the tide of the war effort and undoubtedly save lives on the side of the allies. Turing's team by 1943 finally deciphered the U-boat messages and also advised on encrypting messages between Churchill and Roosevelt. There's no question that Turing's genius in these top secret activities helped the allies shorten the war and defeat Nazi Germany.
The main subject matter in the film "The Imitation Game" was Turing's effort to crack the Enigma code at Bletchley Park. However, one could take away many misconceptions from the movie.
- Turing is portrayed as a classic nerd, having difficulty with social relations. Historical accounts show Turing was a likeable person, but just preferred working alone.
- Colleague Hugh Alexander is portrayed to have been in a power struggle with Turing. Alexander did assume a day-to-day leadership role, but there's no evidence of the deep conflict portrayed in the film.
- The military commander in the film is constantly berating Turing and the team and threatening to shut them down. There's no evidence this really happened.
- Turing does propose marriage to colleague Joan Clarke, then backs off when he admits he is a homosexual. This really did happen, but the back story of Clarke needing to get married to avoid having to return to her parents isn't in the historical accounts.
- The movie depicts a singular breakthrough in cracking the German U-boat code, then decisions by the team to withhold knowledge of Naval activity from their superiors out of concern that the Germans would know they cracked the code. In reality, the code was cracked steadily piece by piece, not with one big breakthrough, and there's no way the team of codebreakers would decide to withhold the information as part of military strategy.
- Turing in the movie has a confrontation with one of his colleagues who admits to being a Russian spy. There's no evidence of this either.
After World War II, Turning continued his pioneering work on computing when there really were no computers. His 1946 paper detailed the design of the first stored program computer, or a machine that electronically stores instructions and data. While others contributed significantly to the design and development of the early computing machines, it is Turing that is considered the "Father of Modern Computers". Turing further developed the ideas of machines that could think. In 1948 he began writing a computer program to play chess, which was ultimately successful but needed more computing power than was available on the machines of the day. This was the earliest work in what is now known as "artificial intelligence". Turing proposed a standard that machines would have to meet to prove that machines could meet that would later be known as the "Turing Test". If a machine could be developed to respond to questions from an interrogator, and the interrogator could not tell the difference between the machine's responses and a human's responses, then the machine would be considered to have passed the Turing Test.
Alan Turing's great work took a terrible turn in 1952 as he was a homosexual in a time where homosexuality was a criminal offense in Britain. A series of odd circumstances - Turing's house was broken into and the suspect was an acquaintance of Arthur Murray who was Turing's lover. During the police investigation, Turing admitted that he'd had relations with Murray which was a criminal act, so Turing was arrested and charged with indecency. Turing pleaded guilty and was given a choice of jail time or probation coupled with a therapy that would supposedly "cure" him of his homosexuality. He chose the latter, and over the next years was given female hormones which did in a way cure him of homosexuality as it made him impotent. He was also stripped of his security clearances and not allowed to work for the government on any cryptography projects, though he was able to continue his academic work.
After the hormone therapy was completed in 1954, Turing was found dead of cyanide poisoning. His death was considered a suicide although the circumstances are still under question. There was a half-eaten apple which could have been a playing out of the poisoned apple in "Snow White". However, the apple was never tested for poisoning and there was no suicide note. A number of other theories were put forward that could have lead to an accidental poisoning. In the movie "The Imitation Game" Turing is at the end depicted as a broken and depressed man who chose the hormone therapy so he could continue to work on his computing machine that he called "Christopher" in honor of his departed friend from boarding school. Again, there's no evidence of this and no way to know if the hormones and impotence led to his suicide or if it was an accident.
As computers in the modern world grew, Alan Turing's legacy and contribution to computing and artificial intelligence is unquestioned. Virtually every computer science course mentions Alan Turing in the history of computing and how he invented the concepts of machines storing computing instructions, and adapting and changing based on its input. What most of the world had no idea about was his contributions in breaking the Nazi Enigma code in World War II, as the work done at Bletchley Park was classified and kept secret for years. The work at Bletchley Park was finally declassified in the 1970s, and Andrew Hodges wrote the definitive biography of Turing which was first published in 1983 and a new edition has been published in 2014. In 2009 British Prime Minister Gordon Brown issued a public apology for the way he was treated, and in 2013 Queen Elizabeth granted a pardon posthumously to Alan Turing.