A knowledge base is a collection of information in a form that allows computers to make inferences. Ox will need a knowledge base of common sense and linguistic information. On the common sense side, lots of work has been done since I was last active in natural language processing. On the linguistic side, some aspects are well served by existing work: for example, there are lots of resources if you want to find all the synonyms of a noun. But there are other tasks that I haven’t found research about yet, like how to relate a compound noun like ‘Adele song’ to what you know about songs.

Here are some existing knowledge bases:

Yago: https://gate.d5.mpi-inf.mpg.de/webyagospotlx/WebInterface
ConceptNet: http://conceptnet.io/
WebChild: https://gate.d5.mpi-inf.mpg.de/webchild/
Knowledge Graph: https://developers.google.com/knowledge-graph/
NELL: http://rtw.ml.cmu.edu/rtw/
Reverb: http://openie.allenai.org/