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Re: Can RDF say anything about anything?

From: Frank Manola <fmanola@mitre.org>
Date: Wed, 12 Feb 2003 08:52:55 -0500
Message-ID: <3E4A51B7.1060607@mitre.org>
To: Graham Klyne <GK@ninebynine.org>
CC: pat hayes <phayes@ai.uwf.edu>, RDF core WG <w3c-rdfcore-wg@w3.org>

Graham--

I like your proposed extension.  I think a similar remark (put somewhat 
more casually), could be helpful in the Primer as well.

--Frank

Graham Klyne wrote:

> 
> [Switching thread to RDF-core]
> 
> At 07:42 PM 2/11/03 -0500, Frank Manola wrote:
> 
>> pat hayes wrote:
>>
>>>> I know this thread has died down, but I'd like to get some 
>>>> clarification
>>>> on exactly what needs fixing in the Primer.  The Primer doesn't say (I
>>>> don't know how to interpret "indicate") "that RDF can be used to let
>>>> anyone 'say anything they want about existing resources' ".  What the
>>>> Primer says, following some examples, is "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]."  That seems like a reasonable statement under the
>>>> circumstances (part of the circumstances being that the Primer is
>>>> clearly not describing a rule that is to be applied by an RDF/XML
>>>> parser).  Are there problems with the actual statement in the Primer?
>>>>
>>>> --Frank
>>>
>>> I think the problem might be with any form of words like "able say 
>>> anything they want". In one way of understanding these words, they 
>>> mean something like, "not prohibited from saying anything they feel 
>>> like saying using the formalism, on any topic they choose", which of 
>>> course is so harmless as an observation that it hardly seems worth 
>>> saying. But in another way of understanding those words is "enabled 
>>> by the formalism to have the ability to express any proposition" 
>>> which is an absurd claim. I think the words were meant in something 
>>> close to the first sense, but are being read in something close to 
>>> the second sense.
>>> Pat
>>
> 
> Yes, but there's something in the *goals* of RDF that aims to be 
> universal, but that goal is not completely achieved, or even possible, 
> technically.  "say anything about anything" is an aspirational statement.
> 
>> I think the main problem is that a comment in the Primer about an 
>> *example* is being used to derive a comment *not* in the Primer about 
>> the power of *the formalism used in the example* (RDF/XML), and then 
>> issues are being raised about the *derived* comment.  I suppose such a 
>> derivation can be made, but I can't see very many readers of the 
>> Primer actually making it, and they would be wrong if they did.  I 
>> certainly can't imagine very many readers of the Primer reading that 
>> statement, and then complaining that they were unable to use rdf:ID as 
>> a predicate (for example).
>>
>> Issues directed at the actual text in the Primer would be things like:
>>
>> 1. Anyone being able to say anything they want about existing 
>> resources isn't a basic architectural principle of the Web.  If that's 
>> an issue, I refer you to [BERNERS-LEE98], which says "The Web works 
>> though anyone being (technically) allowed to say anything about 
>> anything."  I suppose it could be argued that the Primer doesn't 
>> characterize that properly, or use the exact quotation, but the 
>> quotation seems to go even further than the Primer does, if you 
>> interpret it as applying to what RDF allows, rather than what the Web 
>> is trying to do, since it doesn't restrict itself to saying things 
>> about "resources".
> 
> 
> I like that Berners-Lee quote, because I think it is unarguable when 
> applied to ordinary web pages.
> 
> Here's an attempt to build upon that:
> [[
> The Web works through anyone being (technically) allowed to say anything 
> about anything.  RDF is a limited formalism, but follows this ideal by 
> allowing expression of arbitrary propositions about any subject matter, 
> within the limitations of its formalism.
> ]]
> 
> I think it behoves Concepts to be a bit more precise about the extent of 
> that formalism;  Pat used some words recently (something like "binary 
> propositional subset of EC logic") that I'd like to steal.
> 
> #g
> -- 
> 
>> 2.  The examples provided don't illustrate that principle of the Web.  
>> I think that they do, even though they don't do so exhaustively.
>>
>>
>> --Frank
>>
>>
>>>
>>>> "Peter F. Patel-Schneider" wrote:
>>>>
>>>>>
>>>>>  From: Brian McBride <bwm@hplb.hpl.hp.com>
>>>>>  Subject: Re: Can RDF say anything about anything?
>>>>>  Date: Fri, 31 Jan 2003 06:51:29 +0000
>>>>>
>>>>>  > At 09:48 30/01/2003 -0500, Peter F. Patel-Schneider wrote:
>>>>>  >
>>>>>  > >Can RDF say anything about anything?
>>>>>  > >
>>>>>  > >The RDF documents are contradictory on this point.  The Primer 
>>>>> indicates
>>>>>  > >that RDF can be used to let anyone ``say anything they want 
>>>>> about existing
>>>>>  > >resources'' with no exception for the resources used by RDF.
>>>>> [Section
>>>>>  > > 3.2] Concepts says
>>>>>  > >that ``RDF is an open-world framework that allows anyone to 
>>>>> make simple
>>>>>  > >assertions about anything''.  [Section 2.2.6, and elsewhere]
>>>>>  > > However, Concepts also says that ``Certain
>>>>>  > >URIs are reserved for use by RDF, and may not be used for any 
>>>>> purpose not
>>>>>  > >sanctioned the RDF specifications.'' [Section 3.7]
>>>>>  > >
>>>>>  > >What is the situation here?
>>>>>  >
>>>>>  > Peter,
>>>>>  >
>>>>>  > As this comment affects several documents, I'll respond.
>>>>>  >
>>>>>  > As a general point, it is helpful if you can provide links to 
>>>>> the sections
>>>>>  > of documents where you have a problem with the text, or at the 
>>>>> least
>>>>>  > section numbers.
>>>>>
>>>>>  Isn't that what the Search/Find capabilities of browsers are for?  
>>>>> I would
>>>>>  expect that an interested reader would want to know where else 
>>>>> Concepts
>>>>>  talks about being able to say anything about anything.  I've added 
>>>>> section
>>>>>  numbers to my comment above.
>>>>
>>>>
>>>>
>>>> snip
>>>>
>>
>>
>> -- 
>> 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
> 
> 
> -------------------
> Graham Klyne
> <GK@NineByNine.org>
> 


-- 
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 Wednesday, 12 February 2003 08:33:47 EST

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