Re: Proposed response to Golbeck regarding imports issue

Peter,

I expect that there will be many OWL applications that arbitrarily
collect together a set of OWL documents and then reason over their
conjunction. If we could not do this then OWL would be of limited use,
because the only things we could combine would be things that were
explicitly identified as imported by the original authors of the
documents (so much for serendipitous discovery :-<). Now, I agree that
any conclusions made are not necessarily entailed by any one document in
the collection, and thus the person or software tool that combines the
documents must take full responsibility for any conclusions drawn. A
formal way to view such process is think of a virtual OWL document that
simply imports all of the documents in the collection (similar to what
Ian suggested Dan do, but I am suggesting that you do not have to create
a series of bytes that corresponds to this document).  The parenthetical
remark that you oppose is there to indicate that tools are free to
collect any set of documents they wish, combine them, and even do OWL
reasoning on the combination. For these reasons, I find the comment
helpful to readers, especially those who like Dan and Jim, want to
experiment with alternatives to imports. 

Jeff

"Peter F. Patel-Schneider" wrote:
> 
> From: Jeff Heflin <heflin@cse.lehigh.edu>
> Subject: Proposed response to Golbeck regarding imports issue
> Date: Mon, 19 May 2003 13:28:52 -0400
> 
> >
> > The following is a proposed response to Jennifer Golbeck regarding the
> > issue with imports raised in:
> >
> > http://lists.w3.org/Archives/Public/public-webont-comments/2003May/0068.html
> >
> > Dear Jennifer,
> 
> [...]
> 
> > First you discuss the following passage from the reference document,
> > 7.3:
> >
> > "Note that the importing a document is different than creating a
> > namespace reference. owl:imports do not set up a shorthand notation for
> > names as does a namespace reference. On the other hand, the namespace
> > reference does not imply that all (or even any) ontological terms from
> > that namespace are being imported. Therefore, it is common to have a
> > corresponding namespace declaration for any ontology that is
> > imported."
> >
> > You are correct that there are a few problems here: First, we are
> > inventing the term "namespace reference" when we mean "namespace
> > declaration." Second, the point of this paragraph was to comment on why
> > namespace declarations and imports are both needed, not to comment on
> > how systems might follow links. In particular, we were trying to say
> > that they are very different animals. I suggest the following rewording:
> >
> > "Note that although owl:imports and namespace declarations may appear
> > redundant, they actually serve very different purposes. Namespace
> > declarations simply set up a shorthand for referring to identifiers.
> > They do not implicitly include the meaning of documents located at the
> > URI (although some applications may choose to process these documents in
> > addition to the original document). On the other hand, owl:imports does
> > not provide any shorthand notation for referring to the identifiers from
> > the imported document. Therefore, it is common to have a corresponding
> > namespace declaration for any ontology that is imported."
> 
> [...]
> 
> I oppose including the parenthetical remark above.  I believe that such
> permissive statements have no place in our documents.
> 
> Peter F. Patel-Schneider
> Bell Labs Research
> Lucent Technologies

Received on Tuesday, 17 June 2003 09:44:08 UTC