This is a formal ontology of the philosophical writings of G. W. Leibniz, extracted from George Martin Duncan's 1890 anthology The Philosophical Works of Leibnitz. The corpus contains thirty-six selections spanning Leibniz's mature career, from his 1679 commentary on Descartes through the 1716 correspondence with Samuel Clarke. The ontology is grounded in the Basic Formal Ontology and validated for consistency by the HermiT description-logic reasoner.
What this is
Leibniz published almost nothing in his lifetime. His philosophical thought is preserved in dozens of short papers, correspondence, and unpublished manuscripts, scattered across several languages and many archives. Duncan's 1890 anthology was the first major English-language collection of his philosophical work and remains a useful entry point. This ontology renders Duncan's thirty-six selections as a single formal artifact.
The corpus includes the major canonical pieces — the New System of Nature (1695), the Principles of Nature and of Grace (1714), the Monadology (published 1744 from a 1714 manuscript), the five letters to Samuel Clarke (1716), and extracts from the New Essays on Human Understanding — alongside lesser-known polemics, including Leibniz's own annotated reading of Spinoza's Ethics and his Refutation of Spinoza.
The ontology is offered for three uses:
- As a reference structure for scholars who need to characterize Leibniz's commitments precisely.
- As a teaching aid for students reading Leibniz across his thirty-five years of philosophical correspondence and writing.
- As a comparative object. A companion ontology of Spinoza's Ethics exists at spinoza.davidkoepsell.com; comparison between the two is a planned area of follow-up work.
It does not replace prose engagement with the texts. It is a complement, an instrument, an artifact.
No login required. No queries logged. Pure public artifact.
Contents
Browser
Interactive viewer with BFO tree, source-text view, and full-text search across the corpus.
iiMethodology
How the ontology was extracted, validated, and finalized. Tools, decisions, limitations, and known issues.
iiiCitation
How to cite this artifact. BibTeX, Chicago, MLA. The persistent DOI.
ivDownload
The OWL artifact itself. Inspect with Protégé, query with rdflib, reason with HermiT.
What this is not
This is not Leibniz's complete philosophical corpus. It is one rendering of a particular nineteenth-century anthology of Leibniz's work, into a formal vocabulary. The Akademie edition of Leibniz's writings is far larger and is still being edited; this artifact draws only on Duncan's selection, which is shaped by what was scholarly-canonical in 1890.
Many decisions were made in extraction that another scholar might make differently. The methodology page describes those decisions and discloses a known logging issue affecting the source-text-to-class navigation. The ontology is a scholarly artifact open to disagreement, criticism, and replacement by better artifacts.
The reasoner that validated the ontology checked for formal consistency. It did not check for fidelity to Leibniz's text or for philosophical defensibility. Those judgments belong to the reader.
Acknowledgements
The Basic Formal Ontology, on which this work depends, was developed by Barry Smith and colleagues over the past two decades and is documented in Building Ontologies with Basic Formal Ontology (Arp, Smith, and Spear, MIT Press, 2015). The HermiT reasoner is the work of Birte Glimm, Ian Horrocks, Boris Motik, Giorgos Stoilos, and Zhe Wang.
The source text is George Martin Duncan's The Philosophical Works of Leibnitz (second edition, 1890), in the public domain. The digitized copy used was scanned by Cornell University Library and made available through the Internet Archive.
The extraction pipeline is BFO-Agent, an architecture by the same author. Source available at github.com/dkoepsell/bfo-agent.
A note on spelling: Duncan's translation uses the older form "Leibnitz" throughout. The standard scholarly spelling now is "Leibniz" (without the t), which is what this site uses for the title and framing. Internal directory names and citations matching Duncan use the older form. The discrepancy is preserved deliberately.