Alan Turing: computing pioneer, codebreaker, gay icon

This post was written by Courtney and is cross-posted from Queereka.
Today, the 23rd of May, marks exactly one month until the centenary of Alan Turing’s birth. Events have been going on, and will continue to go on, through the whole of this year to celebrate the milestone. You may have seen that next month’s Skepchick Book Club book will be David Leavitt’s biography of Turing, but you may not know much about the man himself – much less about why he warrants a whole year of recognition. As Queereka’s resident Turing geek (official title) I hope I’ll be able to demonstrate what an important figure Turing was, the enormous debt we owe him, and the injustices he faced as a gay man living in the wrong time. Of course, I won’t be able to cover every facet of him, which is why you should definitely join in with next month’s discussion!

Alan Mathison Turing was born on the 23rd of June 1912 to an upper-middle class British family. It didn’t take long for him to show signs of brilliance. As a teenager he attended Sherborne School, where his scientific talents weren’t appreciated by the more classics-focused teachers, leading him to work on them in his own time (including extrapolating Einstein’s doubts about Newton’s laws of motion, completely independently, at the age of sixteen). It was also here that he met and fell in love with a fellow student named Christopher Morcom. Sadly, Morcom died suddenly of tuberculosis near the end of their schooling – it was this event that turned Turing into an atheist and arguably helped shape the rest of his life.

Having won a scholarship to study maths at King’s College Cambridge, Turing was elected a Fellow of the college only a year after graduating with a first-class honours degree. A year after this he published perhaps his most important paper, “On Computable Numbers, with an Application to the Entscheidungsproblem“. In it he introduced what became known as Turing machines – machines capable of performing any mathematical function if it were expressed as an algorithm (a set of instructions for the machine to follow). This theory is central to computer science – in essence, Turing created the theoretical framework for computers in this paper, decades before the first digital computers were built.

If those contributions weren’t enough, Turing went on to even more great things. During the Second World War, he worked at Bletchley Park, the centre of Britain’s codebreaking efforts, where the brightest minds in the country worked together to crack German ciphers. It is believed that these efforts shortened the war by at least two years, potentially saving millions of lives.

Though what was achieved at Bletchley Park was undoubtedly a massive team effort, built upon the previous work of others including Polish cryptanalysts, Turing’s contribution was clearly vital. He shares credit with Gordon Welchman and Harold Keen for the invention of the Bombe, a machine designed to break Enigma, one of the Germans’ major methods of encryption. He worked to make previous methods of decryption more general, robust and efficient. His ideas also fed into the design of Colossus, a machine that cracked the Lorenz cipher, though he wasn’t directly involved in it.

While at Bletchley he gained a reputation as an eccentric. To combat hayfever he’d wear a gas mask while cycling to work, he chained his mug to the radiator to prevent it being stolen, and when the chain came off his bike he didn’t get it fixed. Instead, he counted the number of times the pedals went round and got off in time to adjust it. Turing was awarded an OBE for his war work, but wasn’t allowed to reveal the nature of it due it being classified – the full extent of his contributions would not become clear until after his death.


Alan Turing Memorial, Manchester
The Alan Turing Memorial in Manchester

After the war Turing worked first at the National Physical Laboratory, then the University of Manchester, on early computing machines. He also began to consider the issue of artificial intelligence, formulating the famous Turing test. This states that a computer can be said to “think” if a conversation with it cannot be told apart from a conversation with a human being. In the last two years of his life he turned his mind to mathematical biology, specifically morphogenesis (the study of how organisms develop their shapes), where his work is considered seminal.

(Did I mention he was also a world-class marathon runner? Hey, you have to balance out founding computer science with a little physical exercise.)

As you may have worked out, in addition to all of this Turing happened to be gay. While these days most people in the UK have cottoned on to the fact that being gay is not a bad thing, back then homosexuality was illegal – it was only legalised in 1967. In 1952 Turing spent the night with a young man, Arnold Murray, who was also a petty thief. This would prove to be his undoing. After their encounter Murray and an accomplice broke into Turing’s house – Turing, honest to a fault, reported the crime to the police, but in the process was forced to acknowledge his sexual relationship with Murray. They were both charged with “gross indecency”. Turing lost his security clearance and was also forced to choose between a jail sentence and chemical castration by oestrogen injections. He opted for the latter.

The treatment, which aimed to reduce libido, was humiliating, and didn’t even work as it was “meant” to – Turing’s sexual desires were unaffected, but he became impotent and grew breasts. He couldn’t run any more after his body became bloated thanks to the effect of the hormones he was required to take. Two years after his arrest, on the 7th of June 1954, Turing died aged just forty-one. He had apparently taken his own life by biting into an apple laced with cyanide. Some have speculated whether this could have been an accident, due to him not washing his hands after performing experiments, or even something more sinister – the government viewing him as a liability following his conviction and orchestrating his death. What matters, though, is that the world lost one of its greatest minds prematurely, and wouldn’t have were it not for the horrendous treatment dished out to him simply because of who he was attracted to.

While in his lifetime Turing was wholly unappreciated, since his death and since the work he did during the war has been declassified that has changed. Blue plaques punctuate the route of his life. An entire year of events relating to him have been planned all over the world, from conferences to mass sunflower planting. In 2009, then-Prime Minister Gordon Brown issued an official apology for the way Turing had been treated, saying, “We’re sorry, you deserved so much better”. There have been campaigns to officially pardon Turing and all the other men convincted of gross indecency and to get him on the next £10 note.

Sadly, despite all these gestures, the injustice remains and continues around the world in infinite guises. Perhaps the greatest tribute of all would be to work to make the world a place where no one gets intimidated, prosecuted or killed because of who they are and who they love.

Feature image from the Alan Turing Year website.


Will is the admin of Queereka, part of the Skepchick network. They are a cultural/medical anthropologist who works at the intersections of sex/gender, sexuality, health, and education. Their other interests include politics, science studies, popular culture, and public perceptions and understandings of anthropology. Follow them on Twitter at @anthrowill and Facebook at

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  1. Excellent summary of Turing’s life. I had no idea about the running. I’m eagerly awaiting the arrival of the book (Amazon only had 6 copies left and it’s not on Kindle; I hope everyone has a chance to acquire a copy.)

    I’ve linked Courtney’s post to our Boston Skeptics Book Club page. I think it’s essential background reading.

    1. Thanks so much, I’m glad you found the article useful! I’ve only scratched the surface of what he achieved, but I hope it’ll inspire people to learn more. Hope you enjoy the book as well – I certainly did (though there’s also plenty to discuss!).

      If you want a more in-depth look, there’s a pretty amazing website run by Andrew Hodges, who wrote a much longer biography of him:

  2. Right, Alan should have received a Nobel Prize in Mathematics for his work instead of a death sentence for his sexual orientation. At least he got a decades late apology. In this case, not a hell of a lot better late than never.

    1. I agree wholeheartedly. While I’m so pleased he’s getting the recognition he deserves, it’s come tragically late. That angers and upsets me a great deal. (Some people even say things like “he wouldn’t be getting so much recognition if he weren’t gay”. These people cause me to turn into the Hulk.)

      There’s actually no Nobel Prize in Mathematics (the Fields medal is probably the closest to that). Some say it’s because Alfred Nobel’s wife, but he never married so that’s wrong. It’s most likely because he wanted his awards to celebrate achievements with real world applications and didn’t see mathematics as fulfilling this.

      However, the award considered the Nobel’s equivalent in Computer Science is named after… guess who?

      1. You’re probably referring to speculation that Alfred Nobel had an on-going feud with an important mathematician of his day, Gosta Mittag-Leffler. The claims behind that don’t seem to pan out. As you say, Nobel was not married so an affair does not make sense. Furthermore, there doesn’t seem to be much evidence of high profile meetings where a serious conflict between the two was recorded. Some kind of personal writing of one or the other, somewhere, should at least support the idea if it were accurate.

        Other than the possibility that Nobel thought that mathematics was just too theoretical, there was actually already a high-profile Swedish prize for mathematics being awarded by the king*. The two would thus have been in competition with each other.

        * Interestingly, it was Mittag-Leffler who convinced the king to begin awarding prizes in the field. Perhaps this the real origin of the rumors.

        1. I think that story must have gotten corrupted along the way from “feud with mathematician” to “wife ran off with mathematician”. Always interesting to wonder how these stories develop in the first place. What you said about the existing maths prize makes a lot more sense though.

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