2019/09/01 by Agathoklis Kritsimallis, Kritsimallis, Agathoklis, Ioannis Refanidis +1
Computer Science · #F.4.1 #FOS: Computer and information sciences #I.2.3 #Logic in Computer Science (cs.LO) #Logic, Reasoning, and Knowledge #Multi-Agent Systems and Negotiation #Semantic Web and Ontologies
paper · pdf · doi:10.48550/arxiv.1909.00436
openalex publication_date 2019/09/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The system of Type PDL (τPDL) is an extension of Propositional Dynamic Logic (PDL) and its main goal is to provide a formal basis for reasoning about types of actions (modeled by their preconditions and effects) and agent capabilities. The system has two equivalent interpretations, namely the standard relational semantics and the type semantics, where process terms are interpreted as types, i.e. sets of binary relations. Its satisfiability problem is decidable, as a NExpTime decision procedure was provided based on a filtration argument and it was suggested that the satisfiability problem for τPDL should be solvable in deterministic, single exponential time. In this paper, we address the problem of the complexity of the satisfiability problem of τPDL. We present a deterministic tableau-based satisfiability algorithm and prove that it is sound and complete and that it runs in ExpTime. Additionally, the algorithm detects satisfiability as earlier as possible, by restricting or-branching whenever possible.