Title
On Rational Entailment for Propositional Typicality Logic.
Abstract
Propositional Typicality Logic (PTL) is a recently proposed logic, obtained by enriching classical propositional logic with a typicality operator capturing the most typical (alias normal or conventional) situations in which a given sentence holds. The semantics of PTL is in terms of ranked models as studied in the well-known KLM approach to preferential reasoning and therefore KLM-style rational consequence relations can be embedded in PTL. In spite of the non-monotonic features introduced by the semantics adopted for the typicality operator, the obvious Tarskian definition of entailment for PTL remains monotonic and is therefore not appropriate in many contexts. Our first important result is an impossibility theorem showing that a set of proposed postulates that at first all seem appropriate for a notion of entailment with regard to typicality cannot be satisfied simultaneously. Closer inspection reveals that this result is best interpreted as an argument for advocating the development of more than one type of PTL entailment. In the spirit of this interpretation, we investigate three different (semantic) versions of entailment for PTL, each one based on the definition of rational closure as introduced by Lehmann and Magidor for KLM-style conditionals, and constructed using different notions of minimality.
Year
DOI
Venue
2018
10.1016/j.artint.2019.103178
Artificial Intelligence
Keywords
Field
DocType
Knowledge representation and reasoning,Non-monotonic reasoning,Preferential semantics,Typicality,Rationality
Logical consequence,Arrow's impossibility theorem,Alias,Ranking,Computer science,Propositional calculus,Theoretical computer science,Operator (computer programming),Artificial intelligence,Sentence,Machine learning,Semantics
Journal
Volume
Issue
ISSN
277
1
0004-3702
Citations 
PageRank 
References 
1
0.35
0
Authors
4
Name
Order
Citations
PageRank
Richard Booth1726.23
Giovanni Casini213114.44
Thomas Meyer329124.92
Ivan José Varzinczak422421.76