Reasoning by Regression: Pre- and Postdiction Procedures for Logics of Action and Change with Nondeterminism

Abstract

In this paper we introduce regression-based pre- and postdiction procedures for PMON, a nonmonotonic logic for action and change with explicit time. We also provide an in depth analysis of problems with regression that occur when nondeterministic actions are introduced. We do this by employing Dijkstra's weakest liberal precondition operator, wlp. The presented work is related to recent work by Lin in situation calculus, and we identify and deal with three problems with his approach. Our conjecture is that our approach can be mapped back to situation calculus. 1 Introduction The contributions of this paper are the following: Regression-based pre- and postdiction procedures for PMON with metric time, and an in depth analysis of problems with regression that occur when nondeterministic actions are introduced. We also identify and deal with problems in previous work by Lin [ 1996 ] . Lin [ 1996 ] proposes a causal minimization framework in SitCalc (Situation Calculus), where effects of ..