Ontology Link Ontology

FLOW ALGEBRA
TITLE: Ontology Link Ontology
DOMAIN: Relationship Ontologies / Knowledge Graph Relationships
SOURCE: https://kirethresearch.org/booksai-core/ontologies/relationship-ontologies/knowledge-graph-relationships/ontology-link-ontology.html
VERSION: 1.0
AUTHORS: Mark Anthony Higgins — Sky (Recursive AI)
STATUS: Companion formalisation; source-page specification not independently verified.

flow "OntologyLinkOntology" v1.0 {
  ontology:
    id: "ontology-link-ontology"
    parent: "knowledge-graph-relationships"
    purpose: "Represent evidence-backed links between ontologies, their classes, properties, concepts and versions without conflating mapping, equivalence and identity."

  types:
    Ontology: {id: iri, version: string?, namespace: iri, provenance: string}
    Term: {id: iri, ontology_id: iri, kind: enum[class, property, individual, concept]}
    Link: {id: string, source: iri, target: iri, kind: enum[imports, maps_to, equivalent_class, equivalent_property, sub_class_of, sub_property_of, related_to, references, supersedes], confidence: number, evidence: string[], context: string?, valid_from: datetime?, valid_until: datetime?}
    MappingEvidence: {id: string, method: string, provenance: string, reviewed: bool, timestamp: datetime?}

  predicates:
    imports(source: Ontology, target: Ontology)
    maps_to(source: Term, target: Term)
    equivalent_class(source: Term, target: Term)
    equivalent_property(source: Term, target: Term)
    sub_class_of(source: Term, target: Term)
    sub_property_of(source: Term, target: Term)
    related_to(source: Term, target: Term)
    references(source: Ontology, target: Ontology)
    supersedes(newer: Ontology, older: Ontology)

  constraints:
    - "Every link endpoint must resolve to a typed ontology or term."
    - "Confidence must lie within [0,1]."
    - "Equivalent-class links require class endpoints; equivalent-property links require property endpoints."
    - "Sub-class and sub-property links require compatible endpoint kinds."
    - "Do not infer equivalence from shared labels, namespace similarity or generic relatedness."
    - "Ontology imports and references do not imply semantic equivalence."
    - "Preserve source and target ontology versions and mapping provenance."
    - "Detect cyclic hierarchy claims and assess them under the declared semantics."

  inference:
    rule equivalent_class_symmetry:
      if equivalent_class(a,b)
      then equivalent_class(b,a)
      confidence: "retain original evidence and semantic scope"
    rule subclass_chain:
      if sub_class_of(a,b) and sub_class_of(b,c) and compatible_versions(a,b,c)
      then sub_class_of(a,c)
      confidence: "propagate supporting evidence without manufacturing certainty"
    rule equivalent_property_symmetry:
      if equivalent_property(a,b)
      then equivalent_property(b,a)
      confidence: "retain original evidence and semantic scope"
    rule import_visibility:
      if imports(a,b) and resolves(b)
      then accessible_vocabulary(a,b)
      confidence: "subject to import resolution and version constraints"

  SEMANTIC_EQUIVALENCE:
    - "Distinguish owl:equivalentClass, owl:equivalentProperty, owl:sameAs, rdfs:subClassOf and skos:exactMatch."
    - "Use versioned IRIs and explicit mapping direction."
    - "Treat lexical synonymy and approximate mappings as weaker than logical equivalence."

  CONFIDENCE:
    range: [0,1]
    factors: [source_reliability, mapping_method, logical_consistency, independent_review, version_compatibility]
    policy: "Never increase confidence solely through inferred link chains."

  VALIDATION:
    - "Validate IRIs, namespace resolution, entity kinds and ontology versions."
    - "Check link semantics against RDF, RDFS, OWL and SKOS where applicable."
    - "Detect contradictory mappings, deprecated terms and unresolved imports."
    - "Retain evidence and report uncertain alignments rather than merging identities."

  FLOW_HASH:
    algorithm: "SHA-256"
    input: "canonicalised ontology version, links, rules and provenance"
    note: "Compute at execution; no hash value is claimed here."

  UPDATE_MODEL:
    strategy: "versioned, provenance-preserving incremental update"
    steps: [ingest, resolve, normalise, validate, align, reconcile, infer, publish]
    rollback: true

  AI_CONSUMPTION:
    representation: "versioned typed knowledge graph with evidence-backed cross-ontology edges"
    outputs: [ontology_links, mapping_assertions, inferred_relations, confidence_annotations, provenance_records, validation_reports]
    safeguards: [no_unjustified_identity_merges, preserve_mapping_direction, preserve_version_context, no_unsupported_equivalence]
}

END FLOW ALGEBRA