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Re: Contexts (spinoff from copy and wrap rdf statements)

From: Richard H. McCullough <rhm@cdepot.net>
Date: Sat, 23 Nov 2002 10:41:07 -0800
Message-ID: <001701c2931f$e2f2afe0$bd7ba8c0@rhm8200>
To: "Danny Ayers" <danny666@virgilio.it>, "David Menendez" <zednenem@psualum.com>, "rdfig" <www-rdf-interest@w3.org>
Re: Contexts (spinoff from copy and wrap rdf statementI think either
    http:// = document{ model{S1,S2,...} }
or
    http;// = model = {S1,S2,...}
would work, but you have to ask yourself some questions:
documentX hasContent ?
i.e., 
Does the document contain other things in addition to the model?
Are those other things significant?  Or can we logically ignore them?

Caution:
"document" is the class of documents
"documentX" is an individual document in the class of documents
Your notation sketches the basic idea in terms of classes, but you will be applying the idea to individuals.  It's important to remember that distinction.

Another hint:
You might find the "means" property useful.
    symbol means referent
e.g.:
    a word means a class or an individual
    a class name means all those individuals that are members of the class (or a single, unspecified individual if you're talking "singular" instead of "plural")
    an individual name means a particular individual (a particular resource)

I use "means" to remind myself of the difference between the symbol and the referent(s) that it denotes.  In everyday conversation, words come to us automatically, and we don't have to worry about this subtle distinction.
============ 
Dick McCullough 
knowledge := man do identify od existent done
knowledge haspart list of proposition

  ----- Original Message ----- 
  From: Danny Ayers 
  To: Richard H. McCullough ; David Menendez ; rdfig 
  Sent: Saturday, November 23, 2002 6:12 AM
  Subject: RE: Contexts (spinoff from copy and wrap rdf statements)


   > To talk about something, you need a name which denotes that something.  On the internet, a URL can serve as a name (or an alias if you need an alias for some reason).  The  > something   that a URL denotes is (usually) a physical document on a server on the internet.  That physical document may then refer to other named entities via
     > cross-references, or references embedded in statements which are in the document. 

    For identifiers, we have the URI, which is reasonably well defined in general and within RDF.
    http://www.w3.org/Addressing/URL/uri-spec.html

    The problem here I think is the interpretation of an identified resource that happens to be or include a representation of an RDF model. 

     > I recommend drawing a picture showing each entity, and labeling each with its name & important properties.  In this context, what's important are the relations between the entities. 

    http://x -> URL http://x
    URL http:/x returns x.rdf
    x.rdf == documentX
    documentX hasContent modelX
    modelX = {S1, S2...}

    so in effect 

    http://x = document{model(S1, S2...}}

    where the document could perhaps be seen as the collection of the reified versions of the statements 

    or

    given that http:/x returns x.rdf,
    http://x = modelX = {S1, S2...}

    ?


    ============ 
    Dick McCullough 
    knowledge := man do identify od existent done
    knowledge haspart list of proposition

      ----- Original Message ----- 
      From: Richard H. McCullough 
      To: Danny Ayers ; David Menendez ; rdfig 
      Sent: Saturday, November 23, 2002 4:51 AM
      Subject: Re: Contexts (spinoff from copy and wrap rdf statements)


      I would consider the set of statements in a document (or graph) to be a property/value of the document (or possibly a "part", but I think that's an unnecessarily complicated viewpoint).  Now you can talk about that property/value, define a truth-value property for it, etc.
      ============ 
      Dick McCullough 
      knowledge := man do identify od existent done
      knowledge haspart list of proposition

        ----- Original Message ----- 
        From: Danny Ayers 
        To: Richard H. McCullough ; David Menendez ; rdfig 
        Sent: Saturday, November 23, 2002 3:53 AM
        Subject: RE: Contexts (spinoff from copy and wrap rdf statements)




         
          If you let a resource refer to itself, you can just say
              resource has
                  graph = "...",
                  document = "..."
          (however you want to say it in RDFS)
          so the graph would have a reference to itself and the document,
          and ditto for the document.  

          Having such a "cross-reference" doesn't cause any problems, does it? 

          Probably not. 

          Aren't the graph and document "isomorphic", i.e., logically equivalent, or
          are you talking about a different kind of document here?

          Hmm - that's the crunch I suppose. A HTML document can be a resource and have a URL that can be used as its URI. But do we consider an RDF document in the same circumstances a closed box, or a bunch of 'free' statements..? Similarly, if the HTML doc (let's make that XHTML+XLink) made RDF-friendly statements ("myMetaDataHere: me.rdf") how available to the referrer should those statements (and anything else they refer to), be? 

          I guess this is back into the "dark triples" idea.

          If statements are directly asserted by this then they lose their provenence, if they are quoted/reified then that brings up the question of unquoting/unreification mechanisms.
          Hmm... 

          Cheers,
          Danny.
Received on Saturday, 23 November 2002 14:40:22 GMT

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