THE LEGACY OF ALAN TURING

Sir Dermot Turing discusses his uncle’s work and new book that uncovers the crucial work of Polish codebreakers during the 1930s

Alan Turing was a mathematical genius and is acknowledged as the “Father of Computer Science”. Nevertheless he is best known for his pivotal role at Bletchley Park where he was the leading member of the team that solved many of the problems presented by the german Enigma machine. This included designing the Bombe machine and these breakthroughs played a crucial role in allied victory. Despite his monumental successes, Turing was prosecuted for homosexual acts in 1952 and died two years later in what was officially ruled as a suicide.

Sir Dermot Turing, alan Turing’s nephew, has written several books about his uncle, Bletchley Park and computing. as well discussing his relative’s achievements, Sir Dermot talks about his new book X, Y & Z, which reveals the previously unknown story of the Polish, French and British secret services who worked together to unravel the Enigma machine

WHAT DID TURING ACHIEVE DURING WWII?

Everyone associates alan Turing with Bletchley

Park and the breaking of Enigma. That’s the perception and while it’s not wrong it does conceal other interesting things.

It’s absolutely right that Turing was working on the Enigma problem from the very early days of the war and even before it. What people perhaps don’t appreciate is that the basic answer to Enigma was found before Christmas 1939. Polish codebreakers shared their knowledge a few weeks before war broke out and this gave Turing and his fellow codebreakers the leg up to crack the problem.

That means that if they were on top of Enigma and found their methodology before 1939, what did they spend the rest of the war doing?

What you discover is that Turing was then deployed onto the naval Enigma, which was much harder and central to the Battle of the atlantic. along with other intellectual challenges it occupied him up until 1942. at that point he switched roles and was in charge of some aspects of cipher security and enciphered telephone calls. The germans had eavesdropped on Churchill and roosevelt during their transatlantic phone calls so that was a big security concern. Turing spent 1943 until the end of the war working on that and various other machine problems. all this tells you is that there was more to his wartime career than people are perhaps aware of and that there was more to Bletchley Park than Enigma.

YOU’VE PREVIOUSLY CALLED TURING’S LIFE A “SHAKESPEAREAN TRAGEDY”, WHAT DID YOU MEAN BY THAT?

His life does have a Shakespearean structure to it. The degree to which he was a solitary genius is perhaps overplayed but you’ve certainly got a person who achieved great things only for it to collapse because of what was going on in his private life. He suffered prosecution and had to have hormone implants for a year. Then his life ended tragically with him dying by suicide. The pathos is what makes people very interested in him as a character so he does seem to have the same kind of plot line as a Shakespeare play.

HOW WAS TURING REMEMBERED IN THE FAMILY?

Frankly, when I was growing up he was just somebody clever who had been in the family. People find that remarkable but when you put it in the context that nobody had really heard of him until the 1980s then that kind of explains it.

There were guesses in the family as to what he might have done. He was apparently working for the Foreign Office, which seemed somewhat difficult to swallow. He was also doing work that meant he was exempt from military service, which implied the government was using his talents for what he was actually good at.

I am fairly confident that my grandparents had twigged that he must be doing codebreaking because that would have been the most obvious way to put two and two together.

Obviously they didn’t know for a fact and they certainly didn’t have any idea of how successful the operation had been. When the Bletchley Park revelations eventually came out I don’t think it came as a great surprise to my father.

WHAT IS X, Y & Z ABOUT?

Unlike the alan Turing story this is one that is poorly understood and unknown in the UK. I personally knew very little that there were indications that the Poles had done something on Enigma before Bletchley Park. I discovered that there weren’t many books about it in English, which was curious. When I got into the story I found it was very interesting.

The British codebreakers who ended up at Bletchley Park did not know anything about the german Enigma machine as late as July 1939. They had zero knowledge. How they went from total ignorance in July 1939 to being able to build a machine that could solve the Enigma settings for them within three months was because the Poles told them the answers to all the questions. amazingly they had been working on the problem since 1932 and had solved it.

By pure mathematical analysis they had worked out the wirings and the function of the plug board that were puzzling the British. That’s why Bletchley Park was able to become a success but how that has not been an integral part of the story is quite remarkable.

TO WHAT EXTENT HAS TURING’S WORK OVERSHADOWED THE ACHIEVEMENTS OF OTHER CRYPTOLOGISTS DURING WWII?

His work definitely has overshadowed the achievements of the other codebreakers. For instance gordon Welchman was the co-architect of the Bombe machine and he’s not a household name. His achievement was a very clever modification that made alan Turing’s design workable. It turned a not very good machine into one that was super efficient and usable.

Welchman deserves lots of credit and it certainly wasn’t just Turing who was the only clever guy at the park. There were dozens of them working on all sorts of codebreaking problems, many of which were very difficult. Then there were all the hand ciphers and people don’t realise that was of great importance too. The machines capture the imagination but the old-fashioned manual methods for enciphering were very much in use. all this contributes to the intelligence picture and there were many other people who deserved to be just as famous as alan Turing.

WHAT DO YOU THINK OF THE BELATED RECOGNITION HE HAS RECEIVED IN RECENT YEARS?

He’d probably feel quite negative about it to be honest. He was not a seeker of the limelight and would have abhorred the attention. I certainly think he would have been happier to be remembered for his intellectual achievements than standing as a proxy for gay rights etc. That probably would have made him feel very uncomfortable.

To some extent I find myself trying to correct what I believe to be misconceptions that have arisen from The Imitation Game in particular.

That presents a picture of alan Turing that is perhaps slightly unfair as someone who was socially inept and a difficult work colleague. This was not what people who worked with, and talked to me about him, said.

HOW WOULD YOU DEFINE ALAN TURING’S IMPACT ON THE MODERN WORLD?

We need to remind ourselves that he did more than work on Enigma at Bletchley Park. His contribution that undoubtedly affects everyone’s lives everyday was writing the theoretical basis on which all computing is done. The idea that a machine could be programmed to do more than one task was unimaginable back in the 1930s. To have that vision to say ‘This is possible’ and then to say ‘This is how we do it’ is the thing that has had the biggest lasting impact.

“THERE WAS MORE TO HIS WARTIME CAREER THAN PEOPLE ARE PERHAPS AWARE OF AND THERE WAS MORE TO BLETCHLEY PARK THAN ENIGMA”