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Re: RDFS compatibility information in OWL-DL documents

From: Bijan Parsia <bparsia@cs.man.ac.uk>
Date: Thu, 19 Apr 2007 17:18:38 +0100
Message-Id: <D422DF6C-4B18-4532-8330-0AAB9C5ADCC2@cs.man.ac.uk>
Cc: Alan Ruttenberg <alanruttenberg@gmail.com>, Jeremy Carroll <jjc@hpl.hp.com>, public-owl-dev@w3.org, Tim Berners-Lee <timbl@w3.org>, Alistair Miles <a.j.miles@rl.ac.uk>
To: wangxiao@musc.edu

Meta point: I think you are arguing about things that don't matter.  
There's nothing interesting that follows from a document being  
rdf:type owl:Ontology.

Nothing pragamatic and nothing in the semantics.

This is not productive (for you either!).

On 19 Apr 2007, at 16:57, Xiaoshu Wang wrote:

> Bijan,
>> That also is specious, IMHO. First it conflates two things, 1)  
>> whether there is an autoinclude or a explicit include mechanism  
>> and 2) whether owl:imports can be legally used in this case.
>>
>> In point of fact, it can with no discernable difficulty. And even  
>> if it couldn't, that doesn't preclude an explicit model. Indeed,  
>> it strongly supports it (i.e., merging graphs is outside standard  
>> RDF).
> I didn't say it can't.  I was just saying, if there is auto- 
> include, what is the point of explicit include?

That's *not* what you said. You said that *there is* auto-include,  
hence there is no point to explicit include. However, *even if there  
were* auto-include, there'd STILL be a poin to explicit include,  
e.g., I may want to include axioms from a document whos URI I do not  
mention (otherwise) in my document.

> What kind of difference does it make?

See above. And I am firmly in the "using a uri does not mean you  
meant to include the dereferenced document".

I sincerely hope that in the OWL 1.1 XML syntax we move to using  
XInclude. You're concerns about the "modeling" involved with  
owl:imports are a sink hole of your time. It's not worth it. There's  
nothing deep there, at all, hence nothing to worry about. I regret  
that it gives the appearance otherwise, but I take this to be an  
artifact of a certain style that was prevalent at the time (which is  
why there exists the useless and sometimes harmful owl.owl and  
rdfs.rdfs for example).

In practice, owl:imports (and owl:Ontology) are just magic syntax.  
Thinking of them as a property and a class and wondering if they get  
the modeling "right" is hugely pointless and counterproductive.  
owl:imports is definitely  not flexible enough for what people want  
to do in building their ontologies (we need something like an XML  
Catalog or schemaLocation  or something better as well, because  
people want to work with private variants but not have their URIs all  
screwed up).

So, it think we know where we stand and that's good enough for now.

Cheers ,
Bijan.
Received on Thursday, 19 April 2007 16:18:06 GMT

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