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1936: Post, Turing and ‘a kind of miracle’ in mathematical logic

Published online by Cambridge University Press:  01 August 2016

G. T. Q. Hoare*
Affiliation:
3 Russett Hill, Chalfont St Peter SL9 8JY

Extract

In the 1930s several mathematicians, principally Alonzo Church (1903-1995), Stephen Kleene (1909-1994), Emil Post (1897-1954) and Alan Turing (1912-1954), began investigating the notion of effective calculability. (A function from natural numbers to natural numbers is effectively calculable if there is some finite rule or mechanism which will calculate the value of the function for any natural number.) Central to this activity was the notion of recursiveness. Loosely, recursion is a process of defining a function by specifying each of its values in terms of previously defined values.

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Articles
Copyright
Copyright © The Mathematical Association 2004

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