- From: Jeremy Carroll <jjc@hpl.hp.com>
- Date: Sat, 1 Feb 2003 21:26:40 +0100
- To: www-webont-wg@w3.org
Jeremy (on OWL DL annotations) >>Could I suggest it would be clearer with a new rdfs:Class >> owl:AnnotationProperty >>and we require all annotation properties to be of this class. >> >>This is not my preferred solution Jim: >I could live with this > (in fact, as a tool builder it would be useful >- because we could use subclasses of annotationProperty Aside: that would put you in OWL Full, where owl:AnnotationProperty would be irrelevant, and fairly vacuous. Jos: > well, I just can't for the moment I hope I have been sufficiently clear. This was suggested only as a clarification of what I think the current AS&S text is trying to say about OWL DL (and OWL Lite). It certainly would not help with the underlying semantic failure that AS&S treatment of annotations is simply wrong. My reading of what AS&S currently says about properties in OWL DL is that there are four sorts of property used in OWL (other than the built-ins): - datatype properties These have type owl:DatatypeProperty - object properties which may be a transitive or have a syntactic super property (following subPropertyOf, samePropertyAs and inverseOf links) that is transitive. These have type owl:ObjectProperty - object properties which may have cardinality constraints on them or their subproperties (understood syntactically as above) These too have type owl:ObjectProperty - properties used as annotations These have no type whatsoever (they may not have type rdf:Property). (aside) I think AS&S's "side condition" about transitive properties is an inadequate expression of the syntactic constraint that holds between owl:TransitiveProperty and cardinality restrictions; which precisely because of its subtly is best expressed in syntactic rules. The owl:AnnotationProperty idea comes from seeing it as a mistake to have a distinct syntactic category that is defined in the concrete syntax by an absence of information rather than by the presence of information. My preferred solution merges the syntactic category of annotation property with the other syntactic categories of properties - ending up with five different categories of property in the abstract syntax, but only two markers (owl:DatatypeProperty and owl:ObjectProperty) in the concrete syntax. Jeremy
Received on Saturday, 1 February 2003 15:25:44 UTC