All intermediate logics with extra axioms in one variable, except eight, are not strongly omega-complete

Authors
Citation
C. Fiorentini, All intermediate logics with extra axioms in one variable, except eight, are not strongly omega-complete, J SYMB LOG, 65(4), 2000, pp. 1576-1604
Citations number
14
Categorie Soggetti
Mathematics
Journal title
JOURNAL OF SYMBOLIC LOGIC
ISSN journal
00224812 → ACNP
Volume
65
Issue
4
Year of publication
2000
Pages
1576 - 1604
Database
ISI
SICI code
0022-4812(200012)65:4<1576:AILWEA>2.0.ZU;2-C
Abstract
In [8] it is proved that all the immediate logics axiomatizable by formulas in one variable. except four of them, are not strongly complete. We consid erably improve this result by showing that all the intermediate logics axio matizable by formulas in one variable, except eight of them, are not strong ly omega -complete. Thus. a definitive classification of such logics with r espect to the notions of canonicity, strong completeness, omega -canonicity and strong omega -completeness is given.