The Bank of England have announced that King’s College alumnus and Bletchley Park codebreaker Alan Turing will appear on the new £50 note, expected to be in circulation by 2021.

He was chosen from a list of 989 British figures considered to have made significant contributions to science. The final shortlist contained nine Cambridge alumni, including Rosalind Franklin, Stephen Hawking and Dorothy Hodgkin.

Turing studied mathematics at King’s College from 1931-1934, graduating with a first-class honours degree. He returned to academic life at Cambridge a year later, following his election as a Fellow of King’s College at the age of 22 years old. 

He went on to publish the paper ‘On Computable Numbers’ in 1936, recognised by many to be foundational to modern computer science, before going to work as a cryptanalyst for the British Government at Bletchley Park when war was declared in 1939.

His work here led to the cracking of the ‘Engima’ code, a cipher used by the Germans to protect their military intelligence. Historians have estimated that the efforts of Turing and the team of codebreakers may have saved over 14 million lives, shortening the war by around two years.

After the war, Turing’s pioneering work continued to have a far-reaching impact on the scientific disciplines, particularly in the field of Artificial Intelligence (AI). He developed his ‘Turing Test’ in 1950 as a method for determining whether a computer is capable of thinking like a human being. The test was pivotal in the early development of machine learning, and remains an important concept in the philosophy of AI.

Mark Carney, Governor of the Bank of England, commented: “Alan Turing was an outstanding mathematician whose work has had an enormous impact on how we live today. As the father of computer science and artificial intelligence, as well as a war hero, Alan Turing’s contributions were far ranging and path breaking. Turing is a giant on whose shoulders so many now stand.”