- From: Jos de Bruijn <jos.debruijn@deri.org>
- Date: Mon, 26 Mar 2007 12:43:32 +0200
- To: Dave Reynolds <der@hplb.hpl.hp.com>
- CC: RIF <public-rif-wg@w3.org>, Stijn Heymans <stijn.heymans@deri.org>
> > The embedding in section 3.1 seems a straightforward transcription of > RDF (w/o datatypes) and the associated RDFS inference rules into an > F-logic molecules notation. In the way you are using it is there > anything which makes this different from a notational variant on a > simple triple(s,p,o) predicate? This is indeed a notational variant, if one restricts oneself to only this kind of molecules. > > BTW in our own applications we do make use of what you call > "higher-order" features (especially in queries and in rules) and make > some use of "non-classical" (though those latter uses can often be > addressed by some sort of layered approach). What you mean with "non-classical" in this context? Do you mean things like nonmonotonic negation? > > In section 5 is there a reason that your "RDF interaction axioms" are > one way? If one were trying to use this embedding as a way to perform > inference over RDF then you'd want the reverse direction as well. There are slight differences in the semantics of the subclass constructs in F-Logic and the RDF subclass constructs. In F-Logic, every individual is a subclass of itself, whereas in RDF, only individuals of type rdfs:Class are subclass of themselves. > > [Minor: > - I didn't spot the definition of bl(S), I assume it is just the set > of blank nodes in S You are right. Thanks for spotting this. > - in Definition 2 I suspect you mean ".. or > ContainerMembershipProperty, Resource, Class or Property occurs in *a > non-class position in* S."] Actually, no. When considering such direct embeddings of extensional RDFS, we specifically want to avoid situations where some identifier can be made a subclass of ContainerMembershipProperty, Resource, Class or Property, or one of these identifiers can be made a subclass of some other identifier; this would change the semantics of the language constructs; in that case the direct embedding would no longer work, because it hard-wires the semantics of some of the RDFS language constructs. I think it would have been possible to allow them as the object of an rdf:type triple (this would need to be verified). Best, Jos > > Cheers, > Dave > > Jos de Bruijn wrote: >> Dear all, >> >> At the last face-to-face meeting I mentioned that there is a direct >> semantic correspondence between RDF triples and data molecules of the >> form a[b->>c] in F-Logic. >> >> Find attached a paper which describes an embedding of RDF(S) in F-Logic, >> and presents several results. We also present an extension of RDF with >> rules, and, in general, arbitrary theories. >> >> For the members of this working group, the results on the embedding in >> Theorem 1 and Corollary 1, and the extension in Definition 4, with the >> result in Theorem 5, would be the most interesting. >> >> If we would want to adopt this embedding/extension in RIF, we might want >> to rename "molecule" to "triple", and syntax-wise we might choose >> something like NTriples for representing the statements. >> >> >> >> Best, Jos >> > > > -- Jos de Bruijn, http://www.debruijn.net/ +43 512 507 6475 jos.debruijn@deri.org DERI http://www.deri.org/ ---------------------------------------------- When we remember we are all mad, the mysteries disappear and life stands explained. - Mark Twain
Received on Monday, 26 March 2007 10:44:39 UTC