Indiana Philosophy Ontology Project

The InPhO analyzes over 37 million words of philosophical content from:
Stanford Encyclopedia of Philosophy
Internet Encyclopedia of Philosophy
PhilPapers
HathiTrust/Google Books Collection
The project is committed to open access, with data available via a REST API and source code at GitHub.

Dynamic Ontology
The InPhO is constructed by a novel 3-step semi-automated process, called dynamic ontology:
Data Mining — Natural language processing (NLP) techniques generate statistical hypothesis about the relationships among philosophically-salient topics.
Expert Feedback — These hypotheses are evaluated by domain experts through online interfaces.
Machine Reasoning — Our machine reasoning program uses feedback and statistical measures to populate the ontology.

For more information see https://www.inphoproject.org/.