Alan Mathison Turing was born on 23rd June 1912 in Maida Vale, London. Very early in life, Turing showed signs of the genius he was later to display prominently. He was enrolled at St Michael’s and straight away the headmistress recognised his talent as did many of his subsequent educators. In 1926, at the age of 13, he went on to Sherborne School, a famous independent school in the market town of Sherborne in Dorset. He continued to show remarkable ability in the studies he loved, solving advanced problems in 1927 without having even studied elementary calculus. In 1928, aged 16, Turing encountered Albert Einstein’s work and, not only did he grasp it, he extrapolated Einstein’s questioning of Newton’s laws of motion.
From September 1936 to July 1938 he spent most of his time at the Institute for Advanced Study, Princeton, New Jersey, studying under Alonzo Church. In addition to his purely mathematical work, he studied cryptology and also built three of four stages of an electro-mechanical binary multiplier. In June 1938 he obtained his PhD from Princeton University; his dissertation introduced the concept of ordinal logic and the notion of relative computing.Back in Cambridge, he attended lectures by Ludwig Wittgenstein about the foundations of mathematics. The two argued and disagreed, with Turing arguing that mathematics does not discover any absolute truths but rather invents them. He also started to work part-time with the Government Code and Cypher School (GCCS). During the Second World War, Turing was a leading participant in the breaking of German ciphers at Bletchley Park. The historian and wartime code-breaker Asa Briggs has said; “You needed exceptional talent, you needed genius at Bletchley and Turing’s was that genius.”
By using statistical techniques to optimise the trial of different possibilities in the code breaking process, Turing wrote two papers discussing mathematical approaches which were so ahead of their time that they were not released to the UK National Archives until this year. A GCHQ mathematician said at the time that the fact that the contents had been restricted for some 70 years demonstrated their importance.
In 1945, Turing was awarded the OBE for his wartime services, but his work remained classified for many years.
From 1945 to 1947 Turing lived in Richmond, London while he worked on the design of the Automatic Computing Engine (ACE) at the National Physical Laboratory. He presented a paper on 19th February 1946, which was the first detailed design of a stored-program computer. Although ACE was a feasible design, the secrecy surrounding the wartime work at Bletchley Park led to delays in starting the project and he became disillusioned. In late 1947 he returned to Cambridge for a sabbatical year. While he was at Cambridge, the Pilot ACE was built in his absence. It executed its first program on 10th May 1950.
In 1948, he was appointed Reader in the Mathematics Department at the University of Manchester. In 1949, he became Deputy Director of the Computing Laboratory there, working on software for one of the earliest stored-program computers – the Manchester Mark 1. During this time he continued to do more abstract work in mathematics, and in “Computing machinery and intelligence” with Turing addressing the problem of artificial intelligence.
In 1948, Turing began writing a chess program for a computer that did not yet exist. In 1952, lacking a computer powerful enough to execute the program, Turing played a game in which he simulated the computer, taking about half an hour per move. The program lost to Turing’s colleague Alick Glennie, although it is said that it won a game against a friend’s wife.
His Turing test was a significant and characteristically provocative and lasting contribution to the debate regarding artificial intelligence, which continues after more than half a century. He also invented the LU decomposition method in 1948, still used today for solving matrix equations.
In January 1952, Turing began a gay relationship with a man called Arnold Murray. After Murray helped an accomplice to break into his house, Turing reported the crime to the police. During the investigation, Turing acknowledged a sexual relationship with Murray. Homosexual acts were illegal in the United Kingdom at that time and so both were charged with gross indecency. Turing was given a choice between imprisonment and chemical castration.
Turing’s conviction led to the removal of his security clearance and barred him from continuing with his cryptographic consultancy for the Government Communications Headquarters (GCHQ). At the time, there was acute public anxiety about spies and homosexual entrapment by Soviet agents because of the exposure of Guy Burgess and Donald Maclean as KGB double agents. Turing was never accused of espionage but, as with all who had worked at Bletchley Park, was prevented from discussing his war work.
On 8th June 1954, Turing’s cleaner found him dead; a post-mortem examination established that the cause of death was cyanide poisoning administered from a bite out of a poisoned apple found next to his body. An inquest determined that he had committed suicide, and he was cremated at Woking Crematorium on 12th June 1954.
On 23rd June 1998, on what would have been Turing’s 86th birthday, Andrew Hodges, his biographer, unveiled an official English Heritage Blue Plaque at his birthplace and childhood home in Warrington Crescent, London, later the Colonnade Hotel. To mark the 50th anniversary of his death, a memorial plaque was unveiled on 7th June 2004 at his former residence, Hollymeade, in Wilmslow, Cheshire.
In 1999, Time Magazine named Turing as one of the 100 Most Important People of the 20th Century for his role in the creation of the modern computer, and stated: “The fact remains that everyone who taps at a keyboard, opening a spreadsheet or a word-processing program, is working on an incarnation of a Turing machine.”
On 13th March 2000 a set of stamps to celebrate the greatest achievements of the 20th century were issued, one of which carries a recognisable portrait of Turing against a background of repeated 0s and 1s, and is captioned: “1937: Alan Turing’s theory of digital computing”. On 1st April 2003, Turing’s work at Bletchley Park was named an IEEE Milestone. On 28th October 2004, a bronze statue of Alan Turing sculpted by John W Mills was unveiled at the University of Surrey in Guildford; it portrays him carrying his books across the campus. In 2006, Boston Gay Pride named Turing their Honorary Grand Marshal.
The logo of Apple Computer is often referred to as a tribute to Alan Turing, with the bite mark a reference to his method of suicide. Both the designer of the logo and the company deny that there is any homage to Turing in the design of the logo. On the television quiz show QI presenter Stephen Fry recounted a conversation had with Steve Jobs, saying that Jobs’ response was, “It isn’t true, but God, we wish it were.”
In August 2009, John Graham-Cumming started a petition urging the British Government to posthumously apologise to Alan Turing for prosecuting him as a homosexual. An act thought by many to have led to him committing suicide. The petition received thousands of signatures and Prime Minister Gordon Brown acknowledged the petition, releasing a statement on 10th September 2009 apologising and his “appalling” treatment.
The statement concluded; “Thousands of people have come together to demand justice for Alan Turing and recognition of the appalling way he was treated. While Turing was dealt with under the law of the time and we can’t put the clock back, his treatment was of course utterly unfair and I am pleased to have the chance to say how deeply sorry I and we all are for what happened to him … So on behalf of the British government, and all those who live freely thanks to Alan’s work I am very proud to say: we’re sorry, you deserved so much better!”