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Closing the Circle: An Analysis of Emil Post's Early Work

Published online by Cambridge University Press:  15 January 2014

Liesbeth de Mol
Liesbeth de Mol*
Affiliation:
Centre for Logic and Philosophy of Science, Blandijnberg 2, 9000 Gent, BelgiumE-mail: [email protected]
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Abstract

In 1931 Kurt Gödel published his incompleteness results, and some years later Church and Turing showed that the decision problem for certain systems of symbolic logic has a negative solution. However, already in 1921 the young logician Emil Post worked on similar problems which resulted in what he called an “anticipation” of these results. For several reasons though he did not submit these results to a journal until 1941. This failure ‘to be the first’, did not discourage him: his contributions to mathematical logic and its foundations should not be underestimated. It is the purpose of this article to show that an interest in the early work of Emil Post should be motivated not only by this historical fact, but also by the fact that Post's approach and method differs substantially from those offered by Gödel, Turing and Church. In this paper it will be shown how this method evolved in his early work and how it finally led him to his results.

Type
Articles
Information
Bulletin of Symbolic Logic , Volume 12 , Issue 2 , June 2006 , pp. 267 - 289
Copyright
Copyright © Association for Symbolic Logic 2007

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