W3C home > Mailing lists > Public > www-webont-wg@w3.org > May 2003

Re: Proposed response to Golbeck regarding imports issue

From: Jeff Heflin <heflin@cse.lehigh.edu>
Date: Thu, 29 May 2003 11:50:58 -0400
Message-ID: <3ED62C62.2C41FCD7@cse.lehigh.edu>
To: Ian Horrocks <horrocks@cs.man.ac.uk>
CC: WebOnt <www-webont-wg@w3.org>

I actually like a variation of the wording used in Reference. How about
if we change the wording in Guide, section 2.2 

from:

"owl:imports provides an include-style mechanism. owl:imports takes a
single argument, identified by the rdf:resource attribute. 

Importing another ontology brings the entire set of assertions provided
by that ontology into the current ontology. In order to make best use of
this imported ontology it would normally be coordinated with a namespace
declaration. Notice the distinction between these two mechanisms. The
namespace declarations provide a convenient means to reference names
defined in other OWL ontologies. Conceptually, owl:imports is provided
to indicate your intention to include the assertions of the target
ontology. Importing another ontology, O2, will also import all of the
ontologies that O2 imports."

to:

"An owl:imports statement references another OWL ontology, the meaning
of which is included in the meaning of the importing ontology. The value
of the rdf:resource attribute is a URI that identifies the ontology that
is to be imported.  Importing another ontology, O2, will also import all
of the ontologies that O2 imports.

It is often convenient to coordinate owl:imports with a namespace 
declaration, so that qualified names can be used when referring to the
resources of the ontology. Notice the distinction between these two
mechanisms. The namespace declarations provide a convenient means to
reference names defined in other OWL ontologies, while owl:imports
indicates your intention to include the assertions of the target
ontology."

Note: This also includes other chages proposed in an earlier message,
which are shown for context, and some reordering to better separate
different ideas.

Jeff

Ian Horrocks wrote:
> 
> [snip]
> 
> > >"If an ontology imports another ontology then it virtually includes the
> > >meaning of the imported ontology."
> 
> Couldn't we say something like "If ontology A imports ontology B, then
> the semantics (meanings if you prefer) of terms in A are exactly the
> same as they would be if all of the statements in B (including further
> imports statements) were included in A".
> 
> Ian
Received on Thursday, 29 May 2003 11:51:07 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:58:00 GMT