## Alan Turing

## Alan M. Turing

Alan M. Turing, 1912-06-22/3? - 1954-06-07. A British mathematician, inventor of the Turing Machine. Turing also proposed the Turing test. Turing's work was fundamental in the theoretical foundations of computer science.

Turing was a student and fellow of King's College Cambridge and was a graduate student at Princeton University from 1936 to 1938. While at Princeton Turing published "On Computable Numbers", a paper in which he conceived an abstract machine, now called a Turing Machine.

Turing returned to England in 1938 and during World War II, he worked in the British Foreign Office. He masterminded operations at Bletchley Park, UK which were highly successful in cracking the Nazis "Enigma" codes during World War II. Some of his early advances in computer design were inspired by the need to perform many repetitive symbolic manipulations quickly. Before the building of the Colossus computer this work was done by a roomful of women.

In 1945 he joined the National Physical Laboratory in London and worked on the design and construction of a large computer, named Automatic Computing Engine (ACE). In 1949 Turing became deputy director of the Computing Laboratory at Manchester where the Manchester Automatic Digital Machine, the worlds largest memory computer, was being built.

He also worked on theories of artificial intelligence, and on the application of mathematical theory to biological forms. In 1952 he published the first part of his theoretical study of morphogenesis, the development of pattern and form in living organisms.

Turing was gay, and died rather young under mysterious circumstances. He was arrested for violation of British homosexuality statutes in 1952. He died of potassium cyanide poisoning while conducting electrolysis experiments. An inquest concluded that it was self-administered but it is now thought by some to have been an accident.

There is an excellent biography of Turing by Andrew Hodges, subtitled "The Enigma of Intelligence" and a play based on it called "Breaking the Code". There was also a popular summary of his work in Douglas Hofstadter's book "Gödel, Escher, Bach".