- From: Dan Brickley <danbri@danbri.org>
- Date: Sat, 11 Aug 2007 10:52:58 +0100
- To: Pat Hayes <phayes@ihmc.us>
- CC: John McClure <jmcclure@hypergrove.com>, Bijan Parsia <bparsia@cs.man.ac.uk>, Owl Dev <public-owl-dev@w3.org>
Pat Hayes wrote: > >> >>> But rdf:ID doesn't get you *any sort of >>> declaration*. It's *just a funny way of making an assertion*. >> >> Nope, I don't agree -- I don't see this in the specs anywhere. > > Well, the RDF specs say explicitly that RDF consists entirely of > assertions, they give a normative semantics which defines the > assertions, and they do not mention declarations anywhere. Seems pretty > damn clear to me. Yup, if you're looking for "declarations", you might try to see it social wrappings around pure formal RDF. Like if I use RDFS/OWL to describe some classes and properties, then write that out as an RDF/XML UTF-8 document and publish it, then mail semantic-web@w3.org and say ... 'hey everyone, use my new ontology'. Perhaps after all that we could say the classes and properties have been declared? RDF no more has declarations than it has lies; but people can lie and declare using RDF. <rdf:Property rdf:ID="permits"/> in an RDF/XML document http://example.com/somerdf ...might be read as somehow ensuring that the URI for the term "permits" that it expands to is new, previously unused, etc. And I guess this is why it gets seen as a declaration, since it gives (illusory) impression we can be sure that whoever wrote this is the first to do so. That assumptio is a mistake, since the interaction with xml:base allows pre-existing properties and classes to be further described via rdf:ID. cheers, Dan ps. testcase: <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xml:base="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" > <rdf:Property rdf:ID="permits" dc:description="assertions about cc:permits go here, but if anyone 'declared' it, it wasn't me."/> </rdf:RDF> gives 2 triples: http://creativecommons.org/ns#permits http://www.w3.org/1999/02/22-rdf-syntax-ns#type http://www.w3.org/1999/02/22-rdf-syntax-ns#Property . http://creativecommons.org/ns#permits http://purl.org/dc/elements/1.1/description "assertions about cc:permits go here, but if anyone 'declared' it, it wasn't me." .
Received on Saturday, 11 August 2007 09:53:17 UTC