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Basic Formal Ontology 2.0

What is BFO?​

BFO is a top-level ontology that provides a common framework for describing the fundamental concepts of reality. It is used in a wide range of applications, including ontology development, knowledge representation, and semantic web technologies.

Basic Formal Ontology is currently being used by over 450 ontology-based research projects in biomedical informatics and increasingly in other fields. The course will provide an introduction to the content and use of BFO in ontology development. Attendees will acquire knowledge of the ontology and of its use as top-level ontology in multiple ontology development projects in a variety of fields. They will learn about the most recent developments in the ontology and acquire basic knowledge of the draft version 2.0.

The current version of the draft Specification and User Guide for BFO 2.0 is available here.

The current version of the draft BFO 2.0 OWL file is available here. Please read the release notes

These links, and also further information concerning the draft BFO 2.0 release can be found at the BFO page here: https://github.com/BFO-ontology/BFO

BFO introduction has been given at the BFO Workshop 2012

What is BFO 2020?​

BFO 2020 is the latest version of BFO, which includes a number of new features and improvements over previous versions.

ISO Standardization​

BFO 2020 has been standardized by ISO as ISO/IEC 21838-2:2021. This standard is part of a two-part series:

  1. ISO/IEC 21838-1:2021 - Top-Level Ontologies (TLO)

    • Published August 2021
    • Specifies requirements for top-level ontologies
    • Available at ISO 71954

  2. ISO/IEC 21838-2:2021 - Basic Formal Ontology (BFO)

    • Published November 2021
    • Standardizes BFO 2020 as a top-level ontology conforming to Part 1
    • Available at ISO 74572

The complete BFO 2020 content is freely available at ISO/IEC 21838-2, including:

  • Excel files:

    • bfo-2020-terms.xlsx - Terms and relational expressions with definitions and examples
    • bfo-2020-iris.xlsx - IRIs for all classes and relations
    • bfo-2020-relations-table.xlsx - Table of all relations including inverses and reverses

  • OWL files:

    • bfo-2020.owl - OWL in RDF/XML format
    • bfo-2020.ofn - OWL in functional syntax
    • bfo-2020-labeled.ofn - OWL in functional syntax with labels
    • bfo-2020-without-some-all-times.owl - OWL without binaryized relations

  • Common Logic formalization:

    • Complete set of modules in CL format
    • temporalized-relations.cl - CL definitions of binary temporal relations

  • Additional resources:

    • PDF folder: CL axiomatization in FOL syntax
    • Prover9 folder: Modules in Prover9 format
    • Model folder: Consistency proof models in multiple formats

The most current versions of these files are maintained at BFO-2020 GitHub repository.

For questions about BFO 2020, contact [email protected]

For BFO 2020 (# ISO standard) see here

Release information on BFO github site

Video Introduction to BFO 2.0 (2015)​

Part One​

Part Two​

Background Information​

BFO Website

For introductory reading see: Pierre Grenon and Barry Smith: "SNAP and SPAN: Towards Dynamic Spatial Ontology", Spatial Cognition and Computation, 4 (2004), 69-103.

For introductory reading on relations see: Barry Smith, Werner Ceusters, et al., “Relations in Biomedical Ontologies”, Genome Biology (2005), 6 (5), R46.

For (optional) philosophical discussion of core BFO issues see: Barry Smith and Werner Ceusters, “Ontological Realism as a Methodology for Coordinated Evolution of Scientific Ontologies”, Applied Ontology, 5 (2010), 139–188.

This paper contains some material pertaining to process profiles: “Classifying Processes: An Essay in Applied Ontology”, Ratio, 25:4 (2012), 463-488.

And the paper here contains material on the proposed BFO 2.0 classification of objects: “On Classifying Material Entities in Basic Formal Ontology”, in Interdisciplinary Ontology. Proceedings of the Third Interdisciplinary Ontology Meeting, Tokyo: Keio University Press, 2012, 1-13.

The current draft version of the BFO 2.0 Specification is available here.

For further information please write to [mailto:phismith@buffalo.edu Barry Smith] or see here.