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OpenCyc is back and better than ever!


OpenCyc 2.0 is now available for download from SourceForge.


You can also download OWL versions of the OpenCyc ontology,
or search for and access OpenCyc content on the semantic web, accessing Cyc concepts via their URIs, at sw.opencyc.org.

OpenCyc

OpenCyc is the open source version of the Cyc technology, the world's largest and most complete general knowledge base and commonsense reasoning engine. OpenCyc can be used as the basis of a wide variety of intelligent applications such as:

  • rapid development of an ontology in a vertical area
  • email prioritizing, routing, summarization, and annotating
  • expert systems
  • games

to name just a few.

Release 2.0 of OpenCyc includes:

  • The entire Cyc ontology containing hundreds of thousands of terms, along with millions of assertions relating the terms to each other, forming an ontology whose domain is all of human consensus reality.
  • NEW! 100,000+ "broaderTerm" assertions, in addition to the previous generalization (subclass) and instance (member) assertions, to capture additional relations among concepts.
  • English strings (a canonical one and alternatives) corresponding to each concept term, to assist with search and display.
  • The Cyc Inference Engine and the Cyc Knowledge Base Browser are now Java-based for improved performance and increased platform portability.
  • Documentation and self-paced learning materials to help users achieve a basic- to intermediate-level understanding of the issues of knowledge representation and application development using Cyc.
  • A specification of CycL, the language in which Cyc (and hence OpenCyc) is written.
  • A specification of the Cyc API for application development.
  • Links between Cyc concepts and WordNet synsets.
  • NEW Links between Cyc concepts (including predicates) and the FOAF ontology.
  • NEW! Links between Cyc concepts and Wikipedia articles.

Cyc Training Available

Cycorp will be offering a three-day, hands-on Cyc introductory course in Austin, TX as well as a two-day class covering advanced Cyc topics during May 2010 (exact dates TBD). Click here for additional information or contact us at cyc101 @ cyc.com for information about customized semantic knowledge management or ontology development training.

How to Join
To subscribe to any of our mailing lists, click here.

OpenCyc is being considered as a standard by the IEEE. You can learn about participating in the Standard Upper Ontology working group by visiting http://suo.ieee.org/. Anyone can become a voting member by visiting here.

OpenCyc development is being hosted at:

Get OpenCyc at SourceForge.net. Fast, secure and Free Open Source software downloads

     
click for enlarged image
The OpenCyc KB Browser


Visit the Cyc Foundation, a not-for-profit organization dedicated to growing and sharing the OpenCyc ontology!


Announcements
2009/07/27 - Cycorp is pleased to announce that OpenCyc 2.0 is now available for download from SourceForge.

2009/07/27 - Cycorp is pleased to announce the Cyc ATP Challenges at CASC-22

2008/08/18 - Read about the release of OpenCyc semantic web endpoints and how OpenCyc Brings Meaning to the Web

2007/03/10 - A new, simplified browser is available from The Cyc Foundation to let you explore the contents the OpenCyc ontology.

2006/04/03 - Cyclify Austin meets on the second Thursday of each month in Austin, TX. All members of the OpenCyc community are welcome. For details, please send an email to opencyc@cyc.com.

2004/06/04 - The OWL scaffolding version of OpenCyc v0.7.8b can be found here (>700MB). This file contains #$isa, #$genls and #$comment assertions for over 60,000 Cyc constants. Caution: This file takes approximately 9 hours to load into Protege.

2004/03/26 - The OWL version of OpenCyc v0.6.0b can be found here.

2001/06/07 - The CycML schema document can be found here.