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A simple solution to Friedman's fourth problem

Published online by Cambridge University Press:  12 March 2014

Xavier Caicedo*
Affiliation:
Department of Mathematics, University of Maryland, College Park, Maryland 20742 Departamento de Matematicas, Universidad de Los Andes, Bogotá, Colombia

Abstract

It is shown that Friedman's problem, whether there exists a proper extension of first order logic satisfying the compactness and interpolation theorems, has extremely simple positive solutions if one considers extensions by generalized (finitary) propositional connectives. This does not solve, however, the problem of whether such extensions exist which are also closed under relativization of formulas.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1986

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References

REFERENCES

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