Photograph of Alun Turing © Almany, photographer unknown

I don’t know — one minute you’re being chemically castrated for being a homosexual and the next minute they’re sticking your face on money and hailing you as “The Gay Man Who Saved the World” on the front of Attitude Magazine. On the 7th June 1954, Alan Turing’s cleaner found his body in his flat in Wilmslow, Cheshire 16 days before his 42nd birthday. He had allegedly laced an apple with cyanide. According to a close friend, he had always had an obsession with the film Snow White and was possibly mimicking the scene where the Queen eats the poisoned fruit.

Following a campaign in 2009, PM Gordon Brown made a public apology for the way Turing was treated.

In 2013, Alan Turing was posthumously cleared of all of his convictions and pardoned by the Queen (not the Snow White one). In 2017 ‘Turing’s Law’ granted more pardons to people previously convicted of homosexuality but campaigners argued that this didn’t go far enough.

In 2022, 77 years after this gay man saved the world; finally, anyone with this conviction was pardoned.

It is on Upper Maze Hill, St Leonards that you will come across the plaque in honour of Turing, situated at his childhood home and placed there to mark the Centennial of his birth.

Although he was born in London, Turing had a strong early connection with St Leonards. Between the ages of 6–9 he attended St Michael’s primary school in St Leonards and his genius was recognised by the head teacher there.

Later, at a boarding school in Dorset he showed remarkable ability in solving advanced problems but was criticised for his handwriting. He struggled with English and maths, and was too interested with his own ideas to produce solutions to problems using the methods taught by his teachers.

At Cambridge in 1934, he was awarded a first class honours in mathematics and was highly praised for his dissertation in which he proved a version of the central limit theorem.

In 1936, Turing published his paper On Computable Numbers, with an Application to the Entscheidungsproblem. Turing proved that a ‘Universal Computing Machine’ would be capable of performing any mathematical computation if they were representable as an algorithm.

He struggled with English and maths, and was too interested with his own ideas to produce solutions to problems using the methods taught by his teachers.

In September 1938 Turing started work with the Government Code and Cypher School. He focussed on the Enigma Cipher Machine used by Nazi Germany. In 1939 Dilly Knox and Turing gave the British and French details of their method of decrypting the Enigma Machine’s messages. Turing precipitated the breaking of German ciphers. He was pivotal to what they were doing at Bletchley.

On 4th September 1939, the day after the UK declared war on Germany, Turing reported to Bletchley Park, signing the official Secrets Act. He worked alone on the difficult problem of ‘German Naval Enigma’. In December 1939, Turing solved the essential part of the naval indicator system and that same evening he conceived the idea of Banburismus, a technique to assist in breaking the naval Enigma.

In 1948, Turing was appointed reader in the Mathematics Department at the Victoria University, Manchester and a year later being the deputy director of the Computing Machine Laboratory where he worked on the early stored program computer — The Manchester Mark 1.

Having previously admitted his homosexuality, Turing met a younger male lover who, unfortunately burgled Turing’s home, resulting in the police being involved. In 1952 Turing was convicted of homosexuality, just seven years after he had been awarded an OBE by the Queen for his vital contribution to the war effort. Turing was given treatment that included chemical castration and his conviction resulted in him being barred from continuing with his cryptographic consultancy.

The outcome of the Second World War, without the knowledge and dedication of Alan Turing could have been so different.

Alan Turing had many accomplishments some were never fully recognised in Britain during his lifetime because much of his work was covered by the Official Secrets Act.

In 2019 Alan Turing was named ‘the greatest person of the 20th century’ in the final of the BBC Icons series, beating Pablo Picasso, Nelson Mandela and Dr Martin Luther King Jr.

Turing now has an extensive legacy which includes statues and annual awards for computer innovations. He appears on the Bank of England £50 note, which was released to commemorate his birthday. Not forgetting the plaques, one of which is situated in St Leonards.