YAGO2s is a huge semantic knowledge base, derived from Wikipedia WordNet and GeoNames. Currently, YAGO2s has knowledge of more than 10 million entities (like persons, organizations, cities, etc.) and contains more than 120 million facts about these entities.
- - YAGO is the most popular Web-based alternative to OpenCyc.
- - YAGO is the most popular Open Source & free alternative to OpenCyc.
Freebase is a free, knowledge graph with millions of people, places, and things. Freebase contains tens of millions of topics, thousands of types, and tens of thousands of properties. By comparison, English Wikipedia has over 4 million articles.Discontinued
According to https://developers.google.com/freebase/ the API has been shut down, but there are still data-dumps available.
SWI-Prolog offers a comprehensive Free Software Prolog environment for programming software that does logical reasoning. Together with its graphics toolkit XPCE, its development started in 1987 and has been driven by the needs for real-world applications.
- - SWI Prolog is the most popular Windows, Mac & Linux alternative to OpenCyc.
SWI Prolog Features