Profile: code-breaker Alan Turing
Updated on 11 September 2009
The father of the modern computer, Alan Turing broke the WWII Enigma code - yet he died in shame after being chemically castrated for being gay.
Alan Turning is often called the father of computing.
As a mathematician, logician, cryptanalyst and computer scientist, he helped create the mathematical algorithm and was central to the allies’ successful decryption of German military ciphers during the second world war.
Turing was born in England in 1912. While at Sherborne School, with no training in calculus, he began solving complex mathematical problems.
And it was at Sherborne that Turing fell in love for the first time, with Christopher Morcom. Turing lost his faith and became an atheist when Morcom died after drinking cows' milk infected with bovine tuberculosis.
Turing went to Kings College Cambridge in 1931 where he began his ground-breaking work on algorithms.
In his 1936 paper, On Computable Numbers with an Application to the Entscheidungs Problem, he rewrote what was then the accepted language of computing, replacing it with what is now called the Turing machine – to this day the central object of study in the theory of computing.
He continued his mathematical work at the Institute of Advanced Studies, Princeton University, where he began studying cryptology in September 1936.
The day after the outbreak of world war two, Turing began work at Bletchley Park, the military division of GCCS, where code-breakers strove to decrypt enemy communications.
It was there he turned his attention to breaking ciphers created by the German Enigma machine. Looking similar to a typewriter, the Enigma contained electromechanical rotors that scrambled secret messages into complex ciphers.
The Germans believed it was impenetrable to allies however within weeks Turing had designed a machine he believed would break the code. It was named the Bombe, after the original Polish-designed Bomba and it was installed into Bletchley in 1940.
By then Turing had been appointed as head of "Hut 8", the department responsible for decoding German naval signals. His work in breaking the German Enigma code arguably tipped the balance of the war in Europe in favour of the allies. Many believe it hastened the end by two years.
Later Turing went on to break the Lorenz cipher, the German method of cryptology that replaced the Enigma.
In the spring of 1941, Turing proposed marriage to Hut 8 co-worker Joan Clarke, although the engagement was broken off by mutual agreement in the summer.
In 1945 he was awarded and OBE for his services to the military, although his work remained secret for years. From 1945 to 1952 Turing returned to academia.
In 1952 Turing began an affair with 19-year-old Arnold Murray.
When the relationship soured, Murray broke into Turing's house with an accomplice. Turing reported the incident to the police, but was subsequently forced to admit having a relationship with Murray.
Homosexuality was a criminal offence in England at the time, and Turing was convicted of gross indecency.
He was given a choice between prison or chemical castration. He opted to have oestrogen hormone injections, a procedure which lasted a year. The treatment however had a number of side effects, including the development of breasts.
The incident left his life in ruin.
Turing's security clearance was revoked, making it impossible for him to continue work at Bletchley Park or any other affiliated organisation.
Two years later, on 9 June 1954, Alan Turing was found dead at his home. It is believed he deliberately ate an apple laced with cyanide.
Years later the founders of Apple computers chose to pay tribute to Turing who laid the foundations of the modern day computer with their corporate logo; an apple with a missing bite.
