Exten: A system for computing default logic extensions

Allen P. Courtney, Grigoris Antoniou, Norman Y. Foo

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

2 Citations (Scopus)


This paper descirbes Exten, an object-oriented system for default reasoning. Its current functionality includes the computation of extensions for various default logics. The efficiency of the system is strongly increased by applying pruning techniques to the search tree. We motivate and present these techniques, and demonstrate that they can cut down the size of the search tree significantly. Quite importantly, they complement very well the recently developed stratification method [4] which has proven to be powerful and has been implemented in our system. Exten supports experimentation with default logics allowing the user to set various parameters. Also it has been designed to be open to future enhancements, which are supported by its object-oriented design. Exten is part of our long-term effort to develop an integrated toolkit for intelligent information management based on nonmonotonic reasoning and belief revision methods.

Original languageEnglish
Title of host publicationPRICAI 1996
Subtitle of host publicationTopics in Artificial Intelligence - 4th Pacific Rim International Conference on Artificial Intelligence, Proceedings
EditorsNorman Foo, Randy Goebel
PublisherSpringer Verlag
Number of pages12
ISBN (Print)3540615326, 9783540615323
Publication statusPublished - 1996
Externally publishedYes
Event4th Pacific Rim International Conference on Artificial Intelligence: Workshops on Reasoning with Incomplete and Changing Information and on Inducing Complex Representations - Cairns, Australia
Duration: 26 Aug 199630 Aug 1996
Conference number: 4

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Conference4th Pacific Rim International Conference on Artificial Intelligence
Abbreviated titlePRICAI 1996


Dive into the research topics of 'Exten: A system for computing default logic extensions'. Together they form a unique fingerprint.

Cite this