Artificial Intelligence

This special issue is dedicated to John McCarthy, founding father of Artificial Intelligence. It contains a collection of recent contributions to the field of knowledge representation and reasoning, a field that McCarthy founded and that has been a main ...

In reasoning about actions, it is commonly assumed that the dynamics of domains satisfies the Markov Property: the executability conditions and the effects of all actions are fully determined by the present state of the system. This is true in ...

We describe Modular-E (ME), a specialized, model-theoretic logic for reasoning about actions. ME is able to represent non-deterministic domains involving concurrency, static laws (constraints), indirect effects (ramifications), and narrative information ...

This paper describes our methodology for building conformant planners, which is based on recent advances in the theory of action and change and answer set programming. The development of a planner for a given dynamic domain starts with encoding the ...

McCarthy's Situation Calculus is arguably the oldest special-purpose knowledge representation formalism, designed to axiomatize knowledge of actions and their effects. Four decades of research in this area have led to a variety of alternative formalisms:...

The situation calculus, as proposed by McCarthy and Hayes, and developed over the last decade by Reiter and co-workers, is reconsidered. A new logical variant called ES is proposed that captures much of the expressive power of the original, but where ...

John McCarthy's situation calculus has left an enduring mark on artificial intelligence research. This simple yet elegant formalism for modelling and reasoning about dynamic systems is still in common use more than forty years since it was first ...

Logical filtering is the process of updating a belief state (set of possible world states) after a sequence of executed actions and perceived observations. In general, it is intractable in dynamic domains that include many objects and relationships. ...

We examine four approaches for dealing with the logical omniscience problem and their potential applicability: the syntactic approach, awareness, algorithmic knowledge, and impossible possible worlds. Although in some settings these approaches are equi-...

The concept of a stable model provided a declarative semantics for Prolog programs with negation as failure and became a starting point for the development of answer set programming. In this paper we propose a new definition of that concept, which ...

We first embed Pearce's equilibrium logic and Ferraris's propositional general logic programs in Lin and Shoham's logic of GK, a nonmonotonic modal logic that has been shown to include as special cases both Reiter's default logic in the propositional ...

The addition of aggregates has been one of the most relevant enhancements to the language of answer set programming (ASP). They strengthen the modelling power of ASP in terms of natural and concise problem representations. Previous semantic definitions ...

This paper is an in-depth study of qualitative physical reasoning about one particular scenario: using a box to carry a collection of objects from one place to another. Specifically we consider the plan, plan1 ''Load objects uCargo into box oBox one by ...

This paper investigates the challenging problem of encoding the common sense knowledge involved in the manipulation of spatial objects from a reasoning about actions and change perspective. In particular, we propose a formal solution to a puzzle ...

The well-designed logical robot paradigmatically represents, in the words of McCarthy, the abilities that a robot-child should have to reveal the structure of reality within a ''language of thought''. In this paper we partially support McCarthy's ...

This note describes how the notion of nonmonotonic reasoning emerged in Artificial Intelligence from the mid-1960's to 1980. It gives particular attention to the interplay between three kinds of activities: design of high-level programming systems for ...

We take a fresh look at some major strands in John McCarthy's work from a logician's perspective. First, we re-analyze circumscription in dynamic logics of belief change under hard and soft information. Next, we re-analyze the regression method in the ...