Alan Turing

Legacy & significance

Turing supplied both of AI's founding documents: the 1936 paper proving one universal machine could compute anything computable, and the 1950 paper asking whether machines can think. The first made computers possible; the second made artificial intelligence a research question rather than a fantasy.

Major achievements & key works

• On Computable Numbers (1936). Introduced the Turing machine and universal computation, the theoretical basis of every computer built since.
• Breaking naval Enigma at Bletchley Park (1939-1945). The bombe machines and Banburismus methods he devised shortened the Atlantic war; historians credit the effort with saving vast numbers of lives.
• Computing Machinery and Intelligence (1950). Reframed 'can machines think?' as an operational test, predicted machine learning, and answered Lovelace's objection, the founding paper of AI.
• The chemical basis of morphogenesis (1952). Founded mathematical biology with reaction-diffusion theory, showing his computational lens reached beyond machines.

Pivotal turning points

Year	Event	Impact
1936	Publishes On Computable Numbers at 24	Universal computation defined
1939	Joins Bletchley Park the day after Britain declares war	Begins the Enigma work
1950	Publishes Computing Machinery and Intelligence in Mind	AI's founding question posed
1952	Convicted of 'gross indecency' for his homosexuality	Career destroyed by the state he had served
1954	Dies of cyanide poisoning at 41	Inquest rules suicide
2013	Receives royal pardon; 'Turing's Law' follows in 2017	Formal recognition of the injustice

Sources & further reading

Primary sources

• On Computable Numbers, with an Application to the Entscheidungsproblem (1936), Turing Digital Archive
• Computing Machinery and Intelligence, Mind LIX(236), 1950

Recommended secondary sources

• Alan Turing: The Enigma, Andrew Hodges (1983)
• The Imitation Game (2014 film), dramatized account