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Re: a URI is a name (tel uri scheme and VCARD RDF)

From: Alexander Jerusalem <ajeru@vknn.org>
Date: Mon, 25 Nov 2002 17:37:31 +0000
Message-Id: <5.1.0.14.0.20021125172419.021921d8@pop.gmx.net>
To: "Nikita Ogievetsky" <nogievet@cogx.com>, <www-rdf-interest@w3.org>

Hmm, I think the problem with your solution is that the two statements do 
not have the same subject. Shouldn't it rather be something like:

<rdf:Description rdf:about="12345678901234567890">
   <rtm:shortname>W3C</rtm:shortname>
   <rtm:weburi>http://www.w3c.org"</rtm:weburi>
</rdf:Description>

I know that the rdf:about as above is not valid RDF, I just want to 
illustrate that the contents of the id should be completely meaningless. 
For RDF compliance it should probably be something along the lines of 
rdf:about="urn:12345678901234567890".



At 05:39 25.11.2002 -0800, Nikita Ogievetsky wrote:
>Alexander,
>
>This is actually one of the axioms of Topic Maps [1].
>In my RDF Topic Maps attempts [2] I am defining two RTM properties:
>
><daml:UnumbiguousProperty rdf:ID="indicatedBy">
>  <rdfs:subPropertyOf
>rdf:resource="http://www.daml.org/2001/03/daml+oil#TransitiveProperty"/>
>  <rdfs:domain rdf:resource="#topic"/>
>  <rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/>
>  <rdfs:comment>Subject Indicating Resource</rdfs:comment>
></daml:UnumbiguousProperty>
>
><daml:UnumbiguousProperty rdf:ID="constitutedBy">
>  <rdfs:domain rdf:resource="#topic"/>
>  <rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/>
>  <rdfs:comment>Subject Constituting Resource</rdfs:comment>
></daml:UnumbiguousProperty>
>
>So that I can say in one document:
>
><rdf:Description rdf:ID="w3c">
>   <rtm:indicatedBy rdf:resource="http://www.w3c.org"/>
></rdf:Description>
><rdf:Description rdf:ID="w3cwebsite">
>   <rtm:constitutedBy rdf:resource="http://www.w3c.org"/>
></rdf:Description>
>
>[1] http://www.topicmaps.org/xtm/
>[2] http://www.cogx.com/swglasses.html
>
>--Nikita.
>
>----- Original Message -----
>From: "Alexander Jerusalem" <ajeru@vknn.org>
>To: "Paul Prescod" <paul@prescod.net>; "Richard H. McCullough"
><rhm@cdepot.net>
>Cc: "Doug Ransom" <doug.ransom@alumni.uvic.ca>; <www-rdf-interest@w3.org>
>Sent: Sunday, November 24, 2002 3:55 PM
>Subject: Re: a URI is a name (tel uri scheme and VCARD RDF)
>
>
> >
> > I'm not sure if the following is of any relevance for this thread but your
> > discussion reminds me of a question I have always had regarding RDF:
> >
> > URIs, it seems to me, are used in two completely different ways: On the
>one
> > hand they are just unique names for something. On the other hand they are
> > used to point to something and provide a kind of processing instruction
> > that allows us to physically retrieve the thing it points to. Now when we
> > talk about someone's homepage for example, I don't think it is appropriate
> > to use the URL that allows us to physically retrieve the homepage as the
> > unique name of the homepage. The two roles should be strictly separated.
> > The reason is that I could have made a lot of statements about the
>homepage
> > that use this URI as a unique name, that is as their subject. The physical
> > address, however, can change.
> >
> > So even for internet resources, I think we should have one URI to name it
> > and another one to point at it, even if the two happen to have the same
> > sequence of characters at any one point in time.
> >
> >
> >
> > At 14:48 24.11.2002 -0800, Paul Prescod wrote:
> >
> > >Richard H. McCullough wrote:
> > >
> > >>I followed the link at the bottom of this email, and read Sean B.
> > >>Palmer's interesting essay on URIs.
> > >
> > >I'm not clear on your opinion of Doug's proposal. ;) But you did change
> > >the subject line so I guess we'll treat this as a new thread.
> > >
> > >>For example, if we want to talk about Linus Torvalds in the context of
> > >>URIs & RDFS, we might have three different somethings that we need three
> > >>different names for:
> > >>
> > >>     Linus Torvalds the person
> > >>     a document that contains RDFS statements that describe facts about
> > >> Linus Torvalds
> > >>     a graph that contains nodes and links that describe facts about
> > >> Linus Torvalds
> > >>
> > >>My impression, based on a few RDF-interest emails, is that much
>confusion
> > >>has been generated by trying to use one URI when three URIs are
>required.
> > >
> > >I think that you misunderstand the debate. It is easy to make up three
> > >URIs for Linus Torvalds or ten (let's not forget his home page and email
> > >address and ...). The question is whether the syntactic form of the URI
> > >restricts whether it refers to him, or his home page or the graph or ...
> > >
> > >Seth says:
> > >
> > > >  Linus Torvalda the person
> > > >    http://foo/#LinusTorvalds
> > > >  a documdent that contains RDFS statements that describe facts about
> > > > Linus Torvalds
> > > >    http://foo/
> > > >  a graph that contains nodes and links that describe facts about
> > > Linus > Torvalds
> > > >    http://foo/#ThisGraph
> > >
> > >But an equally consistent position is:
> > >
> > >Linus Torvalds the person
> > >
> > >     http://foo/LinusTorvalds
> > >
> > >   a docudent that contains RDFS statements that describe facts about
> > > Linus Torvalds
> > >
> > >     http://foo/LinusTorvaldsInRDF
> > >
> > >   a graph that contains nodes and links that describe facts about Linus
> > > Torvalds
> > >
> > >     http://foo/LinusTorvaldsGraph
> > >
> > >Insofar as RDF care NEITHER about the syntax of the URI _nor_ the data
> > >referred to by the URI, why should WE care? Why impose a syntactic
> > >convention at all? RDF offers me ways of saying that InRDF is the RDF
> > >representation and Graph is the graph representation of the LinusTorvalds
> > >concept. If Seth wants to use his convention then he can, but he should
> > >also use RDF statements to make explicit the relationship.
> > >
> > >  Paul Prescod
> >
> >
> >
Received on Monday, 25 November 2002 12:38:19 GMT

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