Multiple Ontologies: owl:imports

• owl:imports is either obvious or mysterious

  • Key members of WG (e.g., Pat Hayes and Dan Connelly) have claimed not to understand it
  • Operational meaning (roughly):
    • include all the axioms and facts of the imported ontology (which includes all the axioms and facts of its imported ontologies, etc.)
  • This is (barring syntax tricks like entities) the only way external meanings get into your ontology
    • That is, just using a URI from some other URI space is not enough
    • Transclusion: owl:imports is like <img src=…
    • Link: URI use is (a bit) like <a href=…
    • Work underway (C-OWL, E-connections, PECs, syntactic, etc.)
  • The imports closure is flat

Notes: