Relators

Connecting knowledge subjects via object properties

Relators are knowledge subjects that are not instantiated only by classes but by object properties: they connect two or more other knowledge subjects and may link to each other. The instantiation principle parallels classes; relators are treated as first-class citizens alongside classes.

Composite kinship or social relations are typical applications; see [GuAl2015] for powertype and relator analyses and [FoAl2021] for multi-level modeling. [AlHe2020] relates the idea to RDF/OWL modelling.

Knowledge subjects also connect through chains of object properties, which justify shortcuts such as “aunt” from parent and sibling relations. Relators can define several variants of the same concept depending on which participants are linked.

Explicit triples and rule preconditions should stay consistent when you refactor graphs: relator nodes and plain OP chains are two encodings that must not contradict each other.