Defeasible logic programming 8 dlp is an extension of logic programming capturing commonsense reasoning features, that are dicult to express in traditional logic programming. An example of defeasible reasoning would be the statement that the sun will rise tomorrow. Defeasible logic programming and belief revision uns. Programs are written in the language of some logic. Over the year the logic has been developed and extended, and several variants have been proposed. Defeasible logic programming an argumentative approach. Philosophical foundations of deontic logic and the logic of defeasible conditionals, carlos alchourron, in deontic logic in computer science. This book reports on the development and validation framework to support argumentation in semantic web applications springer theses naeem khalid.
Delp stands for defeasible logic programming, a knowledge representation language, where defeasible and nondefeasible rules can be expressed. In delp, we distinguish between two different sorts of rules. Prolog programming in logic is a representative logic language. We will also discuss briey in this paper how to extend delp for con sidering default negation. Abstract inspired by legal reasoning, this paper presents a semantics and proof theory of a system for defeasible argumentation. The system is fully implemented and is available online lidia 2007, and a brief explanation of its theory is included below.
Embedding defeasible logic into logic programming 3 the paper is organised as follows. The resulting approach is suitable for representing agents knowledge and for providing an argumentation based reasoning mechanism to agents. Argumentbased user support systems using defeasible logic. Recently there has been increased interest in modelling default reasoning by means of rules. Integrating defeasible argumentation with fuzzy art neural. A defeasible logic programmingbased framework to support argumentation in semantic web applications springer theses naeem khalid janjua on. In this paper we compare the expressive power of two approaches in this family of logics. On warranted inference in possibilistic defeasible logic. Defeasible logic is extended to programming languages for cognitive agents with preferences and actions for planning. Find, read and cite all the research you need on researchgate. This webpage provides a web service for defeasible logic programming delp. Elements of defeasible logic programming defeasible logic programming delp combines results of logic programming and defeasible argumentation.
This paper relates the defeasible logic programming delp framework and its semantics sem delp to classical logic programming frameworks. Our results show that the former has a strictly stronger expressive power. Sections 2 and 3 present the basics of defeasible logic and logic programming semantics, respectively. Theory and practice of logic programming most cited. Compilation techniques for defeasible logic programs.
We show that inference in the propositional form of the logic can be performed in linear time. Defeasible logic versus logic programming without negation. We define rulebased agent the ories that contain preferences and actions. Defeasible reasoning is a useful tool when many facts about a situation are unknown. Its inference mechanism, upon a query on a literal in a program, answers by indicating whether or not it is warranted in an argumentation process. Defeasible logic, and sceptical logic programming without negation as failure lpwnf. Advantages of defeasible logic include conciseness and correct handling of the passage of time. There are three rule types in many defeasible logics.
Defeasible logic nute, 1992, extensions of defeasible logic antoniou et a l. Embedding defeasible logic programs into generalized logic programs. In this paper, we provide a theoretical framework for a defeasible deontic reasoning system based on annotated logic programming, we propose an annotated logic program called an evalpsn extended vector annotated logic program with strong negation to formulate a defeasible deontic reasoning proposed by d. The original defeasible logic is ambiguity blocking, but we can also define an. In this article, we propose a recursive semantics for warranted formulas in a general defeasible logic argumentation framework by formalizing a notion of collective nonbinary conflict among arguments. A defeasible logic program is a set p 77, a of hornlike clauses, where 11 and a stand for sets of. Section 4 presents our translation of defeasible theories in logic programs, while section 5 contains the main results.
Defeasible logic, originally created by donald nute with a particular concern about efficiency and implementation, is a simple and efficient rule based nonmonotonic formalism. It is based on the concept of a derivation or proof in d f,r. The work reported here introduces defeasible logic programming delp, a formalism that combines results of logic programming and defeasible. Defeasible reasoning is a rulebased approach for efficient reasoning with incomplete and inconsistent information. A first approach to argumentbased recommender systems. Embedding defeasible logic into logic programming delab. Instead, default reasoning is modelled by rules and a priority relation among them. We begin with agentoriented programming language giving focus to agentspeak language extension found in jason platform, which is the language used to make our approach within the practice. This last approach is used in dprolog nute 1988, defeasible logic nute 1992, extensions of defeasible logic antoniou et al. The model is a sequence of moves in a collaborative group inquiry in which parties take turns making assertions. Pdf a defeasible logic programming system for the web.
In fact, defeasible reasoning in the form of courteous logic programs. Assuring safety in an air tra c control system with. A defeasible logic programmingbased framework to support. Defeasible logic versus logic programming without negation as failure g. It is distinct from fuzzy logic and probabilistic logic, addressing a different set of problems. Defeasible reasoning and logic programming springerlink.
In defeasible logic, there are three different types of propositions. In 29, 2 we have introduced a family of metaprograms for. Defeasible logic is a nonmonotonic logic proposed by donald nute to formalize defeasible reasoning. Strong and default negation in defeasible logic programming. Defeasible logic programming, or delp for short, provides a computational reasoning system that uses an argumentation engine to obtain answers from a knowledge base represented using a logic programming language extended with defeasible rules that stem from the work reported in simari and simari and loui. Relating defeasible and normal logic programming through. Propositional defeasible logic has linear complexity. Defeasible logic programming delp is an argumentationbased reasoning tool that allows users to contemplate reasons for and against certain conclusionsthe warrant status of literals in the. Arguments are expressed in a logicprogramming language with both weak and strong negation, conflicts between arguments are decided with the help of priorities on the rules. The work reported here introduces defeasible logic programming delp, a formalism that combines results of logic. Artificial intelligence research and development lab. Pdf programming cognitive agents in defeasible logic. Ana gabriela maguitman computer science department indiana university bloomington, in 474057104,usa.
Embedding defeasible logic programs into generalized logic. Introduction and motivations possibilistic defeasible logic programming pdelp 10 is a logic programming lan. This is possible through a natural extension of the declarative and procedural semantics of. Argumentbased extended logic programming with defeasible. Defeasible reasoning reasoning with many unknown factors. This statement would not stand up to rigorous reasoning, because the earth could. I present an alternative account of defeasible entailment and show how logic programming offers a paradigm in which the distinction can be captured, allowing for the modeling of a larger range of types of defeat.
Arguments are expressed in a logicprogramming language with both weak and strong negation. Defeasible logic programming an argumentative approach 97 knowledge. Pdf automating defeasible reasoning with logic programming. The presented language can manage defeasible reasoning, allowing the. Delp provides the possibility of representing information in the form of weak rules in a declarative manner, and a defeasible argumentation inference. Download a defeasible logic programmingbased framework. Delp provides the possibility of representing information in the form of weak rules in a declarative manner, and a defeasible argumentation inference mechanism for warranting the entailed conclusions. A delpprogram p is a set of facts, strict rules and defeasible rules.
A redefinition of arguments in defeasible logic programming. In contrast to this, in normal logic programming nlp, there is only one kind. An approach for argumentationbased reasoning using. Citeseerx document details isaac councill, lee giles, pradeep teregowda. As a consequence, the notion of warrant for temporal literals is slightly different from that of delp as. Then we present defeasible reasoning concepts using the defeasible logic formalism and dprolog logical implementation of defeasible logic. Defeasible logic programming delp is a formalism that extends declarative programming to capture defeasible reasoning. A characterization of collective con ict for defeasible.
An important feature of the system is that these priorities are not fixed, but are. Argumentation semantics for defeasible logic oxford academic. We talked about aristotelian logic and how it is useful to ai in another post but twovalued logic that recognises only true or false statements cannot easily deal with natural language, where statements are not clearly true or false, but can have other values inbetween, like. Defeasible reasoning is done using an argumentation formalism. Conflicts between arguments are decided with the help of priorities on the rules. A in these rules are considered to represent classical negation. Inspired by legal reasoning, this paper presents a semantics and proof theory of a system for defeasible argumentation. Such reasoning is, among others, useful for ontology integration, where conflicting information arises naturally. Defeasible logic programming delp 3 is a reasoning framework based on logic programming and defeasible argumentation with a working implementation.
Defeasible logic is a nonmonotonic logic designed to be implemented in prolog 4, 64. Pdf computing temporal defeasible logic researchgate. The work reported here introduces defeasible logic programming delp, a formalism that combines results of logic programming and defeasible argumentation. Execution of a logic program is a theorem proving process. Argument theory change applied to defeasible logic. A defeasible deontic reasoning system based on annotated. Defeasible logic is a rulebased nonmonotonic logic, with both strict and defeasible rules, and a priority relation on rules. Pdf we investigate the complexity of temporal defeasible logic, and propose.