Livre | Chapitre
On the persistent difficulty of disjunction
pp. 77-90
Résumé
We want to show, in this paper, that, in intuitionistic analysis, the union of two closed subsets of Baire space N is not always closed, and that, more generally, the union of a closed set and a II n 0-set is not always II n+10. In the proof of this fact we make use of the intuitionistic Borel Hierarchy Theorem, established in (Veldman, 1981) and (Veldman, 2001a).
Détails de la publication
Publié dans:
Rojszczak Artur, Cachro Jacek, Kurczewski Gabriel (2003) Philosophical dimensions of logic and science: selected contributed papers from the 11th international congress of logic, methodology, and philosophy of science, Kraków, 1999. Dordrecht, Springer.
Pages: 77-90
DOI: 10.1007/978-94-017-2612-2_7
Citation complète:
Veldman Wim, 2003, On the persistent difficulty of disjunction. In A. Rojszczak, J. Cachro & G. Kurczewski (eds.) Philosophical dimensions of logic and science (77-90). Dordrecht, Springer.