Description

• Title:
  Simple Decision Procedure for S5 in Standard Cut-Free Sequent Calculus
• Creator:
  Indrzejczak, Andrzej
• Contributor:
  University of Łódź, Department of Logic;
  indrzej@filozof.uni.lodz.pl
• Description:
  In the paper a decision procedure for S5 is presented which uses a cut-free sequent calculus with additional rules allowing a reduction to normal modal forms. It utilizes the fact that in S5 every formula is equivalent to some 1-degree formula, i.e. a modally-flat formula with modal functors having only boolean formulas in its scope. In contrast to many sequent calculi (SC) for S5 the presented system does not introduce any extra devices. Thus it is a standard version of SC but with some additional simple rewrite rules. The procedure combines the proces of saturation of sequents with reduction of their elements to some normal modal form.
• Object availability:
  free access
• Rights:
  © Copyright by Authors, Łódź 2016; © Copyright for this edition by Uniwersytet Łódzki, Łódź 2016
• Date:
  2017.05.16;
  2016
• Type:
  Article
• Language:
  English;
  eng
• Format:
  application/pdf
• Publisher:
  Wydawnictwo Uniwersytetu Łódzkiego
• Relation:
  Bulletin of the Section of Logic;2;
  45
• Subject:
  Modal logic S5;
  decidability;
  normal forms;
  sequent calculus
• Identifier:
  0138-0680;
  http://hdl.handle.net/11089/21628 ;
  2449-836X;
  10.18778/0138-0680.45.2.05
• Data provider:
  Repozytorium Uniwersytetu Łódzkiego
• Can I use it?:
  seek permission
• Type:
  image