OPINION: Putting codebreaker Alan Turing on new £50 note is an apt tribute

June 23 marks the birthday of Alan Mathison Turing in 1912.

Turing was a mathematician, codebreaker extraordinaire, and pioneer computer genius. This is the day chosen for the issue of the new £50 bank note, the last note to go into polymer mode, rather than what my father called “folding money”.

It is designed by Debbie Marriott, who had been working on it since January 2019, and said it enabled her to know a good deal about Turing’s remarkable life. Turing’s photograph, from 1951, appears on it, and his signature, from the Visitor’s Book in Bletchley Park, where he accomplished such significant work.

Turing has gained universal currency with the 2014 film of his life, The Imitation Game, with the leading role played by Benedict Cumberbatch, and the film is largely faithful to the facts of Turing’s short and highly significant life.

Born in Maida Vale in London, Turing came from a distinguished Anglo-Irish family which included a baronetcy, his father being an engineer in India. He early on showed signs of his latent genius, and also his fortitude and personal will, for example cycling 60 miles from Southampton to Sherborne, so that he could attend Sherborne School, despite the General Strike of 1926.

Educated at King’s College, Cambridge, and at Princeton, in the United States, he ended up as Reader in Mathematics at Manchester University. His 1936 paper, on Computable Numbers, heralded the beginnings not only of computers but of Artificial Intelligence. Firstly came the Idealized computer, The Turing Machine, and then the supervision of the building of the ACE in the National Physics Laboratory.

The new £50 note featuring scientist Alan Turing (Image: PA Media)

But what was to catch the public imagination was revealed only in the 1970s, when due to the Official Secrets Act, what Turing had done at Bletchley Park was disclosed to an astounded public.

Turing had broken the German code, known as Enigma, and this had enabled the Allies to know the secrets of German naval intelligence, thereby it has been estimated, shortening the Second World War by two years, and saving more than 14 million lives.

It is no wonder that it has been said that what he did was the greatest single contribution of all during the war. After the war, in an interview to The Times in 1949, when Turing had gone back to his work on computers, he said: “This is only a foretaste of what is to come, and only the shadow of what is going to be.”

Alan Turing (Image: Archant)

Alas, his private life cut all this short, when in 1951, he was arrested, and charged with homosexual offences. He was convicted, and given the choice of imprisonment or probation with chemical castration. This harsh penalty ended when he took his own life, in a quixotic manner, by eating into an apple laced with cyanide.

The Bletchley Park papers were not fully declassified until 2013, but a public campaign before that had ensured that the prime minister, Gordon Brown, had apologized for what had happened to him in 2009, and the Queen had granted a posthumous pardon in 2014, only the fourth royal pardon issued since 1945.

Not only that, but a 2017 Act retroactively pardoned all those convicted of homosexual offences under historical legislation, especially the infamous Labouchere amendment of 1885.

Turing was both a professional and a private pioneer.

One of the origins of the word ‘gay’, is that it was used by American servicemen in 1942 to signify “G.A.Y.” Good As You.

Turing was not only Good As You, but better than that.