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Positive abstraction and extensionality

Published online by Cambridge University Press:  12 March 2014

Roland Hinnion
Affiliation:
Service de Logique Mathématique, Université Libre de Bruxelles, CP211, Boulevard du Triomphe, 1050 Brussels, Belgium, E-mail: rhinnion@nlb.ac.be
Thierry Libert
Affiliation:
Service de Logique Mathématique, Université Libre de Bruxelles, CP211, Boulevard du Triomphe, 1050 Brussels, Belgium, E-mail: tlibert@ulb.ac.be

Abstract

It is proved in this paper that the positive abstraction scheme is consistent with extensionality only if one drops equality out of the language. The theory obtained is then compared with GPK, a well-known set theory based on an extended positive comprehension scheme.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2003

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References

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