## Abstract A variety of modal logics based on the relevant logic R are presented. Models are given for each of these logics and completeness is shown. It is also shown that each of these logics admits Ackermann's rule γ and as a corollary of this it is proved that each logic is a conservative exte
Models for relevant modal logics
✍ Scribed by André Fuhrmann
- Publisher
- Springer Netherlands
- Year
- 1990
- Tongue
- English
- Weight
- 789 KB
- Volume
- 49
- Category
- Article
- ISSN
- 0039-3215
No coin nor oath required. For personal study only.
✦ Synopsis
Semantics are given for modal extensions of relevant logics based on the kind of frames introduced in I-7]. By means of a simple recipe we may obtain from a class FRM (L) of unreduced frames characterising a (non-modal) logic L, frame-classes FRM m (L:M) eharacterising conjunctively regular modal extensions L.M of L. By displaying an incompleteness phenomenon, it is shown how the recipe fails when reduced frames are under consideration.
1 Richard Sylvan's (nee Routley) work on relevant modal logics has largely remained unpublished. Some of his results may overlap some of mine. As a supervisor of my doctoral thesis, Sylvan has generously advised me over an extended period of time. It is thus a pleasant duty to ascribe to him significant share in the work reported here. Final responsibility for the present article, however, lies solely with me.
📜 SIMILAR VOLUMES
## Abstract We present sequent calculi for normal modal logics where modal and propositional behaviours are separated, and we prove a cut elimination theorem for the basic system K, so as completeness theorems (in the new style) both for K itself and for its most popular enrichments. MSC: 03B45, 03