W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > September 2002

Fw: Datatyping

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Fri, 27 Sep 2002 10:34:18 +0300
Message-ID: <007301c265f8$49fa2420$e180720a@NOE.Nokia.com>
To: "w3c-rdfcore-wg" <w3c-rdfcore-wg@w3.org>



[Patrick Stickler, Nokia/Finland, (+358 40) 801 9690, patrick.stickler@nokia.com]


----- Original Message ----- 
From: "Patrick Stickler" <patrick.stickler@nokia.com>
To: <seth@robustai.net>
Cc: <www-rdf-comments@w3.org>
Sent: 27 September, 2002 10:05
Subject: Re: Datatyping


> I think that we can get the MT to say just about anything
> we want. I'll leave it to Pat and others to comment more about
> that.
> 
> I'm working under the assumption that terms in RDF statements
> are intended in some way to reflect the world (not components
> of structured markup) and that assertions such as those made by 
> rdfs:range are saying something about the thing in the world 
> denoted by the object of the property.
> 
> If the object of the property has fixed meaning, then clearly
> there is a fundamental conflict in the core machinery.
> 
> It is true that one way to "punt" on the whole issue is to
> say that inline literal nodes have no interpretation in RDF
> whatsoever and are simply semantic "wildcards" for applications
> to interpret as they like. I.e. they denote neither strings
> nor values. They denote nothing, mean nothing, and any assertions
> in RDF regarding their meaning are vacuous. They are just syntactic 
> shadows in the abstract graph and the RDF MT does not license
> any entailments whatsoever for statements containing them.
> 
> Now, I don't consider that to reflect the goal and purpose
> of RDF as a language for expressing statements about the
> world such that the truth of those statements can be tested
> and serve as the basis of decisions, but perhaps that's the
> best we can do for now...
> 
> [Patrick Stickler, Nokia/Finland, (+358 40) 801 9690, patrick.stickler@nokia.com]
> 
> 
> ----- Original Message ----- 
> From: "ext Seth Russell" <seth@robustai.net>
> To: "Patrick Stickler" <patrick.stickler@nokia.com>
> Cc: <www-rdf-comments@w3.org>
> Sent: 26 September, 2002 19:10
> Subject: Re: Datatyping
> 
> 
> > Patrick Stickler wrote:
> > 
> > >>Why does the MT *need* to make the triple drawn to the LexicalNode 
> > >>invalid in prescence of a range constraint ?   
> > >>    
> > >>
> > >
> > >Because the range assertion says that the object of the property
> > >is a member of the particular class, and in the case of a datatype
> > >class, its RDF Class extension is the value space. And a lexical
> > >node is not a datatype value, but a string.
> > >
> > It seems to me that the MT's range entailments cannot be applied to 
> > LexicalNodes at all.   This is because however hard we try we simply 
> > could not draw  the arrow {uuu [rdfs:type]  zzz }  as prescribed by the 
> > entailment rule [rdfs3] in the case where uuu is a LexicalNode.    Since 
> > we cannot draw an arrow from a LexicalNode, I propose to change [rdfs3] 
> > to exclude such an erronous entailment .... something like I have 
> > depicted in my new diagram [3].
> > 
> > [3] http://robustai.net/mentography/jenny_mt_rdfs3.jpg
> > 
> > I think this works if  you'all consider a LexicalNode not to be or 
> > rdf:type rdfs:Resource.   Do you?   ... and could the MT be changed as I 
> > propose?  ... and would that solve your concern above?
> > 
> > .... and thanks for your comments in my blog :-) .
> > 
> > Seth Russell
> > http://radio.weblogs.com/0113759/
> > 
> > 
> 
Received on Friday, 27 September 2002 03:37:58 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:51:04 EDT