RE: Anonymous resource names -versus- variables

Well, RDF is a language (written in a language for writing languages).

RDF is for making statements about resources. 


:-----Original Message-----
:From: Graham Klyne [mailto:GK@dial.pipex.com]
:Sent: 08 May 2000 11:29
:To: jos.deroo.jd@belgium.agfa.com
:Cc: www-rdf-interest@w3.org
:Subject: Re: Anonymous resource names -versus- variables
:
:
:At 02:17 PM 5/5/00 +0200, jos.deroo.jd@belgium.agfa.com wrote:
:>Graham Klyne wrote:
:> > This sparks a thought for me:  RDF recognizes two "layers" 
:of statements:
:> >    statements
:> >    statements about statements, via reification
:> >
:> > Your comments suggest another facet of RDF usage:
:> >    statements about representations of statements
:> >
:> > I sense that some discussion of RDF gets mired because of 
:failure to
:> > distinguish between statements, and some representation 
:thereof.  I regard
:> > this as a vital distinction when considering trust 
:representations (an
:> > immediate concern for CC/PP).
:> >
:> > I regard RDF in terms of some homogeneous collection of 
:statements (and am
:> > thinking about building an experimental system that reflects this
:> > view).  Specific statements are added to the collection 
:via documents that
:> > contain representations --in XML or whatever-- but any 
:meaning associated
:> > with a statement must stand when a particular representation in a
:> > particular document is stripped away.
:>
:>I can feel what you mean and please try to demonstate it!
:>A representation 'stands for something' and
:>a statement is 'something that stands' ???
:
:I wouldn't phrase it quite that way (too many 'stands's ;-)
:
:I'll try and construct an example of what I was saying:
:
:Consider maps:  the real world is continuous, and exists all 
:together.  But 
:a map describes some defined part of the world (both 
:geographically and 
:kinds of features).  One map may show the position of a place 
:with respect 
:to geographical features, and another may show its connections 
:with respect 
:to transport (e.g. street map vs Underground map of London).  
:I think maps 
:are like documents containing (representations of) RDF 
:statements, and the 
:real world is what contains the universe of all the things 
:described by the 
:maps, and more.
:
:Further, imagine that the London Transport authority maintain 
:a master map 
:showing where to find all the instances of Underground Maps 
:displayed in 
:the subway system, and a summary of the features contained on these 
:maps.  This might be thought of as a "statement about 
:representations of 
:statements".
:
:A statement that a map was last updated on a particular date 
:is different 
:from saying something about the place where it is posted.
:
:Much of what we know about the real world may be conveyed by 
:maps, but we 
:need to be able to distinguish between a map and the world it 
:describes.  When we destroy a map, the places it describes continue to 
:exist in the same relationships to each other.  Similarly, I 
:think that the 
:logic (whatever that may be) of some collection of RDF 
:statements should 
:stand in the model and associated schema separately from any 
:document that 
:may contain (some representation of) those statements.
:
:#g
:
:------------
:Graham Klyne
:(GK@ACM.ORG)
:

Received on Monday, 8 May 2000 11:29:33 UTC