W3C home > Mailing lists > Public > www-rdf-interest@w3.org > March 2000

Re: Subclass of Thing/Resource

From: Pierre-Antoine CHAMPIN <champin@bat710.univ-lyon1.fr>
Date: Fri, 03 Mar 2000 09:01:47 +0100
Message-ID: <38BF716B.B8F587BC@bat710.univ-lyon1.fr>
To: Tim Berners-Lee <timbl@w3.org>
CC: ML RDF-interest <www-rdf-interest@w3c.org>
Tim Berners-Lee wrote:
> >Sure a web page or an e-mail address IS NOT the corresponding person.
> >Neither is its employee ID...
> 
> No. Either can be used to identify a person.
> http://www.w3.org/DesignIssues/Identity.html#Expressing
> 
> >Though, could we prevent people using the dublin core properties this way :
> >
> ><rdf:Description about="http://www.somewhere.org/somedoc">
> >  <dc:Creator rdf:resource="mailto:John@somewhere.org"/>
> >  <dc:Creator rdf:resource="http://www.somewhere.org/~Paul/"/>
> >  <dc:Creator rdf:resource="employee://somewhere.org/12345"/>
> ></rdf:Description>
> >
> >I don't think so !
> 
> Yes we can, I hope!  IMHO the above is a mess.  Is this what dc expect to
> happen?
> 
> 0. We could define (if starting from zero) define dc:creator to have range
> dc:person where
> a person is the domain of properties dc:mailbox and sc:homepage and
> dc:commonname.
> That is the best solution.

do it, and people will write things like

<play:Person rdf:about="mailto:John@somewhere.org"/>
<play:Person rdf:about="http://www.somewhere.org/~Paul/">
<play:Person rdf:about="employee://somewhere.org/12345"/>

et voila ! The above dc:creator statements are valid.
This is what makes RDF flexible enough to scale the web.

> >URIs are ambiguous, yes, they have more than one interpretation level, yes.
> 
> No, no. We should be clean or no reasoning from all this will be possible.
> IMHO.

My belief is that SOME reasoning will be possible,
even if hard logic inference (with completeness and everything) will not.
We won't prove theorems, no - but is there any universal truth among the web, anyway ?

> >We can't prevent people from using URI with different interpretations,
> >so we'll have to use the context to tackle with it.
> 
> we agree to differ then.

well, I meant, we sure can ENCOURAGE people to use strict structures,
and if they do, RDF agents will be able to perform very efficient and powerful reasoning.
but we can't rely on it - if navigator did rely only on HTML recommendation, 3/4 of the web would be unreadable!
one eroneous fact in a strict logical system can make the entire system contradictory ;
the web can not afford strict logic : its first axiom is "there is contradiction".

I'm thinking about writing a paper on the subject.
I'll post it on the list.

  Pierre-Antoine

> >--- Quid quid Latine dictum sit, altum viditur
> >    Whatever is said in Latin sounds important.
> 
> sed quid quid in RDF dictum sit, altum est.

sure :D
Received on Friday, 3 March 2000 03:00:17 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:51:42 GMT