Re: Some thoughts on the semantics of domain and range (was: Re: RDFS bug "A property can have at most one range property")

rdfs:domain and rdfs:range were modelled after the similarly named
concepts
in Cycl and have had very well defined meanings right from the beginning.

(rdfs:domain ?arc ?domain) ^ (?arc ?source ?target) => (rdf:type ?source
?domain)
and
(rdfs:range ?arc ?range) ^ (?arc ?source ?target) => (rdf:type ?target
?range)

and thats it.

Allowing multiple rdfs:domain/rdfs:range with disjunctive semantics is a
bad idea
because it makes the system non-monotonic. Conjunctive semantics are fine
and
possibly useful.

guha