- From: McBride, Brian <brian.mcbride@hp.com>
- Date: Mon, 10 Nov 2008 07:34:27 +0000
- To: Story Henry <henry.story@bblfish.net>, "Booth, David (HP Software - Boston)" <dbooth@hp.com>
- CC: Pierre-Antoine Champin <swlists-040405@champin.net>, Peter Ansell <ansell.peter@gmail.com>, Semantic Web <semantic-web@w3.org>
> > Yes, if there were one simple thing I could change about the RDF > > specification it would be to remove that silly prohibition against > > having a literal as the subject of an assertion. > > I think the RDF semantics allows this, just not the RDF/XML syntax. [bwm] Its risky jumping into the middle of a thread you haven't been following, but I saw this in passing and ... My understanding of the intent behind the current recommendations produced by the RDFCore working group was to keep the restriction from the 1999 spec that literals could not be subjects, but prepare the ground to allow a future working group to remove this restriction. Thus the restriction is imposed in the abstract syntax of RDF, but the semantics document was written to accommodate an extension. I don't have the specs to hand so can't check the details. Brian > > In Section 1.4 of http://www.w3.org/TR/rdf-mt/ > [[ > if E is a ground triple s p o. then I(E) = true if > > s, p and o are in V, I(p) is in IP and <I(s),I(o)> is in IEXT(I(p)) > > otherwise I(E)= false. > ]] > > In section 1.3 IEXT is defined as > > [[ > A mapping IEXT from IP into the powerset of IR x IR i.e. the set of > sets of pairs <x,y> with x and y in IR . > ]] > > IR is defined in the same paragraph as: > [[ > 1. A non-empty set IR of resources, called the domain or universe of I. > ]] > > Ie a relation can be between anything. > > In RDF/XML you can always get the same effect in the end by using > owl:sameAs in the style of this turtle: > > [] owl:sameAs "http://example/new-term"^^xsd:anyURI . > :obsoleteUri "http://example/old-term"^^xsd:anyURI . > > Henry
Received on Monday, 10 November 2008 07:35:21 UTC