TURING, Alan Mathison (1912-1954). 'On computable numbers, with an application to the Entscheidungsproblem. A correction.' Offprint from: Proceedings of the London Mathematical Society, ser. 2, vol. 43. London: 1937. 8° (275 x 184mm). 4pp., 544-546. (Creasing and soiling to gutter.) Original olive-green wrappers, stapled (one staple lacking, wrappers soiled and detached). Provenance: R.O. Gandy (small correction in pencil to first page).

TURING, Alan Mathison (1912-1954). 'On computable numbers, with an application to the Entscheidungsproblem. A correction.' Offprint from: Proceedings of the London Mathematical Society, ser. 2, vol. 43. London: 1937. 8° (275 x 184mm). 4pp., 544-546. (Creasing and soiling to gutter.) Original olive-green wrappers, stapled (one staple lacking, wrappers soiled and detached). Provenance: R.O. Gandy (small correction in pencil to first page).

TURING'S FINE-TUNING OF HIS MOST IMPORTANT AND LASTING ACHIEVEMENT IN MATHEMATICS. Turing's 1936 classic 'On Computable Numbers' was a response to the Hilbertian question, 'is mathematics decidable? Unfortunately, the Swiss mathematician, Paul Bernays, noticed some errors, and as a result Turing published this correction the following year. In fact, there were other mistakes and inconsistencies in 'On Computable Numbers' noticed by Emil Post (see lot 48; Hodges p.133 and n.3.13). Despite this, it was Turing's unique approach and conception of machines to attack mathematical problems that laid the foundations for modern digital computing. Newman 1937d.