Title
A note on admissible rules and the disjunction property in intermediate logics
Abstract
With any structural inference rule A/B, we associate the rule $${(A \lor p)/(B \lor p)}$$ , providing that formulas A and B do not contain the variable p. We call the latter rule a join-extension ( $${\lor}$$ -extension, for short) of the former. Obviously, for any intermediate logic with disjunction property, a $${\lor}$$ -extension of any admissible rule is also admissible in this logic. We investigate intermediate logics, in which the $${\lor}$$ -extension of each admissible rule is admissible. We prove that any structural finitary consequence operator (for intermediate logic) can be defined by a set of $${\lor}$$ -extended rules if and only if it can be defined through a set of well-connected Heyting algebras of a corresponding quasivariety. As we exemplify, the latter condition is satisfied for a broad class of algebraizable logics.
Year
DOI
Venue
2012
10.1007/s00153-011-0250-y
Arch. Math. Log.
Keywords
Field
DocType
latter rule,admissible rule,extended rule,algebraizable logic,structural finitary consequence operator,variable p,intermediate logic,disjunction property,lor p,latter condition,structural inference rule
Discrete mathematics,Combinatorics,Quasivariety,Heyting algebra,Finitary,Admissible rule,Operator (computer programming),If and only if,Rule of inference,Mathematics,Intermediate logic
Journal
Volume
Issue
ISSN
51
1-2
1432-0665
Citations 
PageRank 
References 
6
0.50
2
Authors
1
Name
Order
Citations
PageRank
Alexander Citkin170.91