Imagine where we would be if computers had never been invented. We wouldn’t have cell phones, video games, smartwatches, robots, or even the Internet. You wouldn’t even be reading this article right now.

All of these things are possible because of one man who was not only a brilliant mathematician and theorist who invented the computer, but also a gay man living at a time when it was illegal in the UK to engage in homosexual acts.

Today, June 23rd, on the occasion of Turing’s birthday, the British government will release a new £50 note to commemorate his life and achievements. According to Jeremy Fleming of the Bank of England, Turing’s appearance on the new currency not only recognizes his scientific contributions but “confirms his status as one of the most iconic LGBT+ figures in the world.”

A quirky, often misunderstood misfit 

Alan Mathison Turing was born on June 23, 1912. An odd child, today we might think of him as a nerd who was fascinated by science.

Growing up, Turing had few friends and was a bit of an outcast. Rather than the usual teenage pursuits, he kept mostly to himself, running his own chemistry experiments in his spare time. His loneliness was abated when he met Christopher Morcom, another boy who was fascinated by science. Turing’s romantic feelings for Morcom may have been Turing’s first indication that he was homosexual. His friend’s death four years later from tuberculosis crushed the young Turing, who remained close with Morcom’s family for years afterward. 

After a bit of difficulty completing his exams, Turing was accepted at King’s College, Cambridge, and in 1934 he graduated with a first-class honors degree in mathematics. He was elected a Fellow of King’s College in 1935 when he was just 22. Then in 1938, he obtained his Ph.D. in Mathematics from Princeton University.

According to biographer Andrew Hodges, when he was growing up, Turing’s family “thought of him a devoid of common sense, and he in turn would rise to the role of absent-minded professor, brilliant but unsound.”

And indeed, throughout his school days and into professional life, Turing was known for his disheveled clothing, ink on his collar, and a disregard for many social norms. He didn’t typically acknowledge hierarchies or demonstrate due respect for authority. As biographer Hodges noted, Turing’s superiors called him an “undisciplined’ person who thrived on the lack of uniformity and the absence of any emphasis on rank.”

Most of the people who knew him might have characterized him as eccentric. He didn’t fit in most places, though he did make friends. Often, though, he just wanted to be left alone to work out the solutions to complex problems that frequently even his professors and colleagues didn’t understand. Moreover, some of the people who worked for him found him difficult to talk to or actively disliked him. But there’s no evidence he was cruel or unreasonable. It seems that he just didn’t make time for people who didn’t have a piece of the puzzle that he needed to solve a problem.

Contributions to code-breaking helped the Allies win WWII

Turing’s whole life centered on answering big questions, often using an unusual combination of mathematics and physics, and later also biology. His goal was to build a universal machine that could perform many different actions, such as doing computations, sorting a list, or running a series of permutations. While there were calculators that could do basic mathematical functions, back in the 1930s and 1940s, there was no such thing as a ‘computer’ as we know it.

During World War II his work with machines led him to a position in the Government Code and Cipher School at Bletchley Park, one of over 12,000 people who worked round the clock to break German Enigma codes. Turing designed the Bombe, an early electronic machine that ran all the permutations of the Enigma code output, allowing the British to decrypt German transmissions and know where the Germans planned to attack and the locations of their ships. 

Turing personally cracked the code that was used by the U-boats in the North Atlantic, something that had bedeviled the British Navy since the outset of the war. According to the BBC, Winston Churchill once said, “The only thing that ever really frightened me during the war was the U-boat peril.”

By the end of the war, the British could decode all German naval messages. Most accounts of the Bletchley operation note that the work of Turing and others shortened the war in Europe by two to four years, and likely saved millions of lives.

For his contributions to code-breaking, Turing was appointed an officer of the Order of the British Empire in 1946.

Inventor of the computer

After the war, Turing never stopped asking questions. He accepted a position at the National Physical Laboratory, where among other things, he pondered how his universal machine would work logically. The Universal Turing Machine would include instructions, data, and processing all on one machine using an electronic memory. He worked on speech encryption and research for the Automatic Computing Engine (ACE). 

Turing’s work not only led to the first electronic computer, but he was the first to develop algorithms, as well as the theoretical basis for programming such computers, the use of binary arithmetic, the concept of software, and computer memory and storage. As he would comment about the ACE, “This is only a foretaste of what is to come, and only the shadow of what is to be”

Then in 1948, Turing joined Max Newman’s Computing Machine Laboratory at the Victoria University of Manchester. He worked on the Manchester computers and, in his free time, picked up gardening, which led him to study plants and morphogenesis

He also was obsessed with the idea of making a machine that could learn — an electronic brain — and did the first work in what would later be called artificial intelligence. 

Despite all of his achievements, during his lifetime Turing never received much public acknowledgment for his accomplishments because many of the projects he worked on were protected by the Official Secrets Act. Even his family was unaware of many of the things he achieved until long after his death.

Turing’s final years were anything but celebratory

Despite all of his contributions to help win the war and then invent the computer, Turing’s life would take a dark turn when he was arrested in 1952. 

He had started a casual and short-lived affair with a young man he had met in Manchester. This man, Arnold Murray, took advantage of his good nature and helped a friend steal a few items from Turing’s home. When Turing reported the crime to the police, the authorities quickly figured out the relationship between Turing and Murray, and arrested Turing for “gross indecency.” 

At the advice of his brother and his solicitor, Turing pled guilty to keep the matter relatively quiet. Then, rather than go to prison, where he would not be able to continue his work, Turing chose chemical castration. He was given treatments of Diethylstilbestrol, a form of estrogen, for two years. 

By being a homosexual at a time when this was illegal and considered deviant behavior, Turing was, according to his biographer Hodges, “living an imitation game, not in the sense of conscious play-acting, but by being accepted as a person that he was not.”

Turing’s death and the lingering controversies

Turing died on June 7, 1954, at the age of 41. The official cause of death was suicide, and the prevailing belief is that he dipped his nightly apple into cyanide and ate it before bed. However, some people (including some of his friends and family) never accepted his death was a suicide. Despite his conviction, he remained in good spirits overall and had stopped taking the estrogen treatments, and had a good job, so it made little sense that he would have killed himself. Never having stopped his personal chemistry experiments, Turing had been doing gold plating using a form of cyanide, and many of the people who knew him best suggested he may have poisoned himself accidentally.

There are some who have also suggested he might have been murdered, as it was a prevailing belief among security services that homosexual men posed a security risk, and with the Cold War ramping up with the Soviet Union, it’s possible that someone in the government believed he might have been given his cryptographic knowledge to the Soviets.

After his death, Turing might have faded into obscurity, but there are just enough people who knew what he had accomplished and who worked to restore his legacy and accord him the honors and acknowledgment he deserved. 

Turing’s major accomplishments

Why is Turing important? 

Before Turing came around, “computers” were human beings who did mathematical calculations, usually women. It was difficult, tedious work. (The 2016 film Hidden Figures depicts the Black women who served as human computers at NASA and did the mathematical calculations that put a man on the moon).

Turing was the first person to have an idea for an electronic computer, and the first person to work out the theories for how such a machine would work. This universal machine was, according to Hodges, “the focal, revolutionary idea of Turing’s life.”

Turing imagined his universal machine as being able to do more than just calculations, all based on the instructions given to it. His concept allowed for computers to be able to do graphic design, play music, and engage in communication. And when the Internet was developed, it didn’t require new machines to work. Existing computers just needed different instructions.

In addition to inventing the computer, Turing is also the father of computer programming and algorithms. He realized that someone would have to come up with the algorithms that would ask the questions, and then the machines would answer them. As noted in Scientific American, Turing “was the first to understand that instructions are themselves data, making algorithms capable of the recursive thinking that makes humans unique.” 

Turing also was the first to theorize about artificial intelligence. In 1950 he published a paper entitled “Computing machinery and intelligence,” and believed that in time, computers would be able to think for themselves. 

To determine whether a computer had developed intelligence, he devised what is now known as a Turing Test, in which a human has to determine if an answer to a question came from another person or from a computer. If they cannot distinguish the response, the computer has passed the test and is considered intelligent.

And if you think the computers of Turing’s day are far removed from the devices you use, consider this:  CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) — those tests that prove you’re a human, with photos of traffic lights or scrambled letters, owe their existence to Turing’s research. And Hodges notes that search engines are based on the algorithms Turing developed to break codes.

Turing’s pardon and enduring legacy

For all that he contributed to society, his legacy was tarnished by his conviction for gross indecency. The first effort to gain a pardon for Turing was in 2009 when a computer programmer named John Graham-Cumming created a petition on the UK Government’s website. Thanks to the BBC and social media, the petition collected 30,000 signatures and led to British Prime Minister Gordon Brown making an official public apology:

“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.”

However, there was no pardon in 2009, or after a similar petition drive in 2011. However, in 2013—not even ten years ago— in response to increasing pressure in Parliament, led by John Leech, the MP for Manchester Withington, Queen Elizabeth II finally granted Turing a posthumous pardon. 

And then in 2017, also thanks to work done by Leech, the British government passed what’s known as the “Alan Turing law” that retroactively pardons other men who were convicted for homosexual acts. 

Although few truly appreciated his contributions when he was alive, today there is an extensive list of programs, statues, and buildings worldwide that honor Turing. For example, several roads in the UK are named after Turing, while in Redmond, Washington, there’s a street adjacent to Microsoft’s main campus named after him. The Turing programming language was developed at the University of Toronto in 1982, while The University of Texas at Austin created the Turing Scholars, an honors computer science program. Istanbul Bilgi University hosts an annual conference called “Turing Days” that focuses on computing theory.

And of course, in 2014 Benedict Cumberbatch starred as Turing in the film The Imitation Game. 

How Turing ended up on the £50 note

To commemorate what would have been Turing’s 109th birthday today, June 23, 2021, Turing’s likeness, as well as designs that reflect his scientific achievements, will appear on the Bank of England £50 note that will enter circulation today.

Andrew Bailey of the Bank of England explained that they reached out to the public to nominate scientists that they would like to see featured on a banknote. After receiving 250,000 nominations, they ultimately selected Turing. 

According to The Verge, some of the design elements on the new currency include “technical drawings for the bombe, a decryption device used during WWII; a string of ticker tape with Turing’s birthday rendered in binary (23 June 1912); a green and gold security foil resembling a microchip; and a table and mathematical formulae.” And Bailey noted that there will also be a sunflower-shaped foil patch containing the initials “AT”, representing Turing’s work in morphogenetics.

The bill will be made from polymer rather than paper and will join the £5 note featuring Churchill, the £10 with Jane Austen, and the £20 with J.M.W Turner. 

Final thoughts

It seems worth reflecting on the life of a man who did so much to advance technology — whose work made possible the equipment used to write this article, host the content on the Internet, and allow you to read it — but who was not adequately respected or appreciated for his inventions while he lived. Indeed, it is worth pondering how a man whose work for the British government ended a devastating world war could have been prosecuted not a decade later by that same government solely for his sexual orientation. 

This is one of the enduring facts of Alan Turing. Intolerance cut short his career and, arguably, his life. He was only 41 when he died. What might he have done with another 40 years? And it begs the question: what other scientific or cultural genius might be getting harassed at this very moment for their skin color, ethnicity, or gender identity? If the life of Turing teaches us anything, it’s that we should embrace difference, not put walls around it.

Jeremy Fleming, the Director of Government Communications Headquarters, or GCHQ, may have said it the best:

“Alan Turing’s appearance on the £50 note is a landmark moment in our history. Not only is it a celebration of his scientific genius which helped to shorten the war and influence the technology we still use today, it also confirms his status as one of the most iconic LGBT+ figures in the world. Turing was embraced for his brilliance and persecuted for being gay. His legacy is a reminder of the value of embracing all aspects of diversity, but also the work we still need to do to become truly inclusive.”

Sources:

• Andrew Hodges, Alan Turing: The Enigma (Princeton University Press, 2014)

• Will Computers Ever Know Everything and How Alan Turing Invented the Computer Age (Scientific American)

• New U.K. Currency Honors Alan Turing, Pioneering Computer Scientist and Code-Breaker (National Public Radio)

• Difficult to Decode: Alan Turing’s Life and its Implications (Harvard University Graduate School of Arts and Sciences)

• Alan Turing: The codebreaker who saved ‘millions of lives’ (BBC)
• The UK’s new £50 note celebrates Alan Turing with lots of geeky Easter eggs (The Verge)

• The new £50 note unveiled and Banknote character – speech by Andrew Bailey (The Bank of England)

• The complete text of Gordon Brown’s apology to Alan Turing

• Alan Turing and Legacy of Alan Turing (Wikipedia)

Decoding an enigma: our tribute to Alan Turing .