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UK unveils £50 note honoring WWII codebreaker

March 25, 2021

Alan Turing's image, along with a landmark mathematical formula he developed, will be featured on Britain's highest-value bank note.

https://p.dw.com/p/3r6et
Bank of England new £50 banknote featuring WWII code-hacker Alan Turing.
Turing laid the groundwork for modern computer science and artificial intelligence Image: Bank of England/REUTERS

The Bank of England flew the rainbow flag on Thursday as it unveiled the design of a new £50 bank note celebrating the mathematician Alan Turing.

The renowned mathematician is known for helping end World War II with his code-breaking skills and is believed to have committed suicide following a homosexuality conviction. 

"There's something of the character of a nation in its money," Bank of England Governor Andrew Bailey said in a statement on Thursday as he highlighted the breadth of Turing's accomplishments. 

"He was also gay, and was treated appallingly as a result," Bailey said. "By placing him on our new polymer £50 bank note, we are celebrating his achievements, and the values he symbolizes."

'A foretaste of what is to come'

The new bank note carries a mathematical formula that Turning wrote in a 1936 paper that laid the groundwork for modern computer science. 

The note also features a quote by Turing about the rise of machine intelligence: "This is only a foretaste of what is to come, and only the shadow of what is going to be."

Handout from the Bank of England showing draft design for new 50 pound banknote. Archive image from 2019.
The draft design was first made public in 2019, with the new note itself unveiled on ThursdayImage: picture-alliance/dpa/Bank of England

The £50 note will enter circulation on June 23, Turing's birthday. It is the Bank of England's highest-value bank note. Turing replaces steam engine pioneers James Watt and Matthew Boulton.

Cracking Nazi codes

Turning cracked the Nazi Enigma code by building on the works of Polish mathematicians who discovered how to read it.

He built an electro-mechanical machine, which foreshadowed the computer, to break the "unbreakable" code that Nazis used to pass orders to their command chain. 

An actor dressed as a German soldier shows the use of the Enigma machine in Bletchley Park Museum in Bletchley, central England, September 6, 2006.
The Bletchley Park Museum in Bletchley, central England, re-created the way Turing broke the Enigma code. Image: Alessia Pierdomenico/REUTERS

Historians credit Turing's work with ending the war early and saving thousands of lives.

He also developed the a test to determine if machines are capable of human-like intelligent behavior. The "Turing test" became cornerstone of the philosophy and ethics of what is now known as artificial intelligence.

Chemical castration and early death

In 1952, Turning was convicted of gross indecency for having sex with a male partner. He was sentenced to chemical castration and elected to take a course of female hormones injections rather than go to prison.The sentence cost him his security clearance to work with Britain's GCHQ spy agency. 

He used cyanide to kill himself two years later, according to an inquest at the time. At the time of his death, his part in the war effort was a strict state secret.

Mathematician Alan Turing
The war hero, whose deeds were not public knowledge at the time of his death, committed suicide after being subjected to chemical castration by the British governmentImage: picture-alliance/CPA Media Co. Ltd

The head of GCHQ, Jeremy Fleming, said Turing's image on the note was a historical moment.

"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," Fleming said.

In 2013, Queen Elizabeth granted Turning a royal pardon for the 1952 criminal conviction. A year later, the film The Imitation Game, which won an Oscar, showcased Turing's story.

Gay sex was illegal in Britain until 1967. The "Alan Turing Law" in 2017 retroactively pardoned all men who had been convicted of gross indecency. 

fb/msh (AP, Reuters)