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Open AccessJournal ArticleDOI

Über eine bisher noch nicht benützte erweiterung Des finiten standpunktes

Von Kurt Gödel
- 01 Dec 1958 - 
- Vol. 12, pp 280-287
TLDR
In this paper, Bernays has pointed out that, in order to prove the consistency of classical number theory, it is necessary to extend Hilbert's finitary stand-point by admitting certain abstract concepts in addition to the combinatorial concepts referring to symbols.
Abstract
Zusammenfassung P. Bernays hat darauf hingewiesen, dass man, um die Widerspruchs freiheit der klassischen Zahlentheorie zu beweisen, den Hilbertschen flniter Standpunkt dadurch erweitern muss, dass man neben den auf Symbole sich beziehenden kombinatorischen Begriffen gewisse abstrakte Begriffe zulasst, Die abstrakten Begriffe, die bisher fur diesen Zweck verwendet wurden, sinc die der konstruktiven Ordinalzahltheorie und die der intuitionistischer. Logik. Es wird gezeigt, dass man statt deesen den Begriff einer berechenbaren Funktion endlichen einfachen Typs uber den naturlichen Zahler benutzen kann, wobei keine anderen Konstruktionsverfahren fur solche Funktionen notig sind, als einfache Rekursion nach einer Zahlvariablen und Einsetzung von Funktionen ineinander (mit trivialen Funktionen als Ausgangspunkt). Abstract P. Bernays has pointed out that, in order to prove the consistency of classical number theory, it is necessary to extend Hilbert's finitary stand-point by admitting certain abstract concepts in addition to the combinatorial concepts referring to symbols. The abstract concepts that so far have been used for this purpose are those of the constructive theory of ordinals and those of intuitionistic logic. It is shown that the concept of a computable function of finite simple type over the integers can be used instead, where no other procedures of constructing such functions are necessary except simple recursion by an integral variable and substitution of functions in each other (starting with trivial functions).

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