Some Theories With Positive Induction of Ordinal Strength ... (1996)
by
Gerhard Jäger
,
Thomas Strahm
| Venue: | JOURNAL OF SYMBOLIC LOGIC |
| Citations: | 7 - 3 self |
BibTeX
@ARTICLE{Jäger96sometheories,
author = {Gerhard Jäger and Thomas Strahm},
title = {Some Theories With Positive Induction of Ordinal Strength ...},
journal = {JOURNAL OF SYMBOLIC LOGIC},
year = {1996},
volume = {61},
pages = {818--842}
}
Bookmark
 |
 |
 |
 |
 |
 |
OpenURL
Abstract
This paper deals with: (i) the theory ID # 1 which results from c ID 1 by restricting induction on the natural numbers to formulas which are positive in the fixed point constants, (ii) the theory BON() plus various forms of positive induction, and (iii) a subtheory of Peano arithmetic with ordinals in which induction on the natural numbers is restricted to formulas which are \Sigma in the ordinals. We show that these systems have proof-theoretic strength '!0.
