- From: Pat Hayes <phayes@ai.uwf.edu>
- Date: Thu, 27 Sep 2001 19:49:26 -0500
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: www-rdf-logic@w3.org
>From: Pat Hayes <phayes@ai.uwf.edu> >Subject: Re: model theory for RDF/S >Date: Thu, 27 Sep 2001 12:48:54 -0500 >> > >> >6. has the implication that ``classes'' have to be resources (i.e., not >> >literals that are not resources). This is not captured in the RDF section >> >of the model theory document. >> >> Seems to me that these conditions only have any effect on the formal >> language in RDFS, since RDF has no way to refer to classes as such, >> including the class of properties. RDF properties - ie arc labels in >> an RDF graph - are required (by the RDF syntax) to be URIs which are >> required (by the model theory) to denote resources (members of IR), >> but I don't see any other consequences of this for the meanings of >> any expressions in the actual formal language until we get to RDFS. > > > > Pat > >Unless a query language for RDF cares about this sort of stuff. Ah, I see. Indeed, if a query language wanted to be able to retrieve literal bindings to its query variables, then the model theory would not currently sanction that in any case. I propose to simply wait until the query languages are sorted out. They may have almost no contact with any model-theoretic notion of entailment or validity. If they want to allow bindings to literals, then we can rewrite the model theory to suit, at some cost in notational complexity but no fundamental change; in particular, the other entailments will still be kosher. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 home 40 South Alcaniz St. (850)202 4416 office Pensacola, FL 32501 (850)202 4440 fax phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes
Received on Thursday, 27 September 2001 20:49:30 UTC