Re: Can RDF say anything about anything?

Peter F. Patel-Schneider wrote:

> From: Frank Manola <fmanola@mitre.org>
> Subject: Re: Can RDF say anything about anything?
> Date: Thu, 13 Feb 2003 14:38:07 -0500
> 
> 
>>Peter--
>>
>>Thanks for this comment.  Regarding the situation you bring up, the
>>Primer at that point says:
>>
>>
>>>These examples also illustrate one of the basic architectural principles 
>>>of the Web, which is that anyone should be able say anything they want
>>>about existing resources [BERNERS-LEE98]. 
>>>
>>[BTW:  If nothing else, you've enabled me to spot a missing "to" in the
>>sentence.  Thanks!]
>>
>>Specifically, the examples illustrate an independent party commenting on
>>a description produced by someone else.  That (roughly) "anyone should
>>be able to say anything about anything" is being cited as an
>>architectural principle of the Web illustrated by the examples, not as a
>>capability of RDF (and certainly not without exceptions).  I frankly
>>find it hard to see anyone reading this, and being led to believe that
>>they can then make RDF statements that violate RDF/XML (e.g., using
>>rdf:ID as a predicate was one of the examples that came up in your
>>interaction with Brian).  Of course, being able to "say anything about
>>anything" provides the ability to state lies and nonsense (e.g., you
>>could say rdf:ID rdf:type ex:MooCow), but we can't really prevent that. 
>>Do you see a particular clarification that would help, such as a caveat
>>here that there are technical limits to RDF's ability to express things?
>>
>>--Frank
>>
> 
> Either RDF is able to ``say anything [...] about existing
> resources'', in which case the sentence is germane, or it isn't, in which
> case the sentence is irrelevant or misleading.  If RDF doesn't satisfy the
> principle then there is no reason to keep the allusion.
> 
> I find this a general problem with the RDF documents.  A lofty principle is
> stated, such as ``say anything ...'' or ``expressing information
> ... without loss of meaning'', but RDF doesn't even come close to the
> principle.
> 


Peter--

I understand your concern, but at the same time what you suggest ("If 
RDF doesn't satisfy the principle then there is no reason to keep the 
allusion") seems awfully black and white.  It seems to me reasonable to 
be able to state the principle, even when we can't totally achieve it 
(and of course, RDF is not alone in not coming close to this principle 
in reality).  I agree, though, that an *uncaveated* statement of this 
principle could be misleading.  What about adding the caveat that I 
mentioned, that there that there are technical limits to RDF's ability 
to express things?

--Frank


-- 
Frank Manola                   The MITRE Corporation
202 Burlington Road, MS A345   Bedford, MA 01730-1420
mailto:fmanola@mitre.org       voice: 781-271-8147   FAX: 781-271-875

Received on Monday, 17 February 2003 10:08:22 UTC