The World at War 1939-1944: A Brief History of World War II. Materials for the Use of Army Orientation Program.

[TURING, Alan].

$20,000.00

Item Number: 135225

Washington: The Infantry Journal, 1945.

The father of computer science, Alan Turing’s copy of the U.S. War Department Military Intelligence Division’s official history of World War II. Small octavo, original wrappers as issued. From the library of Alan Turing with his ownership signature to the title page, “A.M. Turing.” English mathematician, computer scientist, and cryptanalyst Alan Mathison Turing was highly influential in the development of theoretical computer science, providing a formalization of the concepts of algorithm and computation with the Turing machine, a model of the general-purpose computer. During the Second World War, Turing was a leading participant in the breaking of German ciphers at Bletchley Park. As a part-time worker with the Government Code and Cypher School (GC&CS), he concentrated on cryptanalysis of the ‘Enigma’ cipher machine used by Nazi Germany. By using statistical techniques to optimize the trial of different possibilities in the code breaking process, Turing made an innovative contribution to WWII cryptanalysis. He wrote two papers discussing mathematical approaches, The Applications of Probability to Cryptography and Paper on Statistics of Repetitions which were of such value to GC&CS and its successor GCHQ that they were not released to the UK National Archives until April 2012, shortly before the centenary of Turing’s birth. In 1949, Turing became deputy director of the Computing Machine Laboratory, where he worked on software for one of the earliest stored-program computers. During this time he developed the Turing test, an attempt to define a standard for a machine to be called “intelligent,” a reversed form of which is now widely used: the CAPTCHA test, which is intended to determine whether the user is a human or a computer. In very good condition. Housed in a custom half morocco clamshell box. A fascinating association copy.