Re: Action-166 Draft sketch of how to serialize rdf annotation spaces - separate files

From: Alan Ruttenberg <>
Subject: Re: Action-166 Draft sketch of how to serialize rdf annotation spaces - separate files
Date: Wed, 16 Jul 2008 16:26:23 -0400

> On Jul 16, 2008, at 4:08 PM, Peter F. Patel-Schneider wrote:
> >> The part that I was specifically trying to enable was reasoning
> >> within
> >> the annotations, for example to allow for domain and ranges on
> >> annotation properties. This is the part that I didn't see how to
> >> manage
> >> comfortably within a single file.
> >
> >
> > Why not?  In particular, why not use something analogous to the
> > process
> > from the paper you cite?
> I was worried that was a lot more mechanism, and that given where we
> were in the process, the desire to get something in to this release of
> OWL, and the desire to keep to schedule and move quickly towards last
> call, the amount of work associated with doing that might have been
> considered too much. I didn't want to have proposing that much change
> put the possibility of getting *something* in this space out of reach.

More mechanism than using a separate file?  I view using a separate file
as a *very* heavyweight mechanism. 

> In addition there were two technical details which I wasn't sure were
> covered by the paper. The first is annotations on annotations. I did
> want to make sure some version of this is possible as I am aware of
> several use cases in current projects that need it. 

But your proposal only allows a particular kind of very simple
annotations on annotations.  I don't see how that is adequate.  If you
think otherwise please put forward the use cases.

> The second was the
> issue of how to view that proposal from an RDF point of view.

Well, one could just say that the current situation (plus the obvious
extension to annotations on annotations) is the RDF point of view for
the treatment in the paper.
> I did note that the reification of the axioms and associated ontology of
> OWL axioms proposed by the paper seems to not be incompatible with what
> I've proposed- in the sense that I can see how one could script the
> creation of the reified axioms, and then import that into the second
> file.

Surely it is easier to do this without having to invoke a
special-purpose file-handling mechanism.

> However, I like that paper and its approach and if the WG were wiling to
> seriously consider what it proposes I'd certainly support that.

Me too.  

Here is a quick summary of what I see as the gist of the proposal in the
paper.  I'm leaving out a few details.

Regular reasoning on an ontology proceeds as normal in OWL 2 DL.
Annotation reasoning on an ontology O is done by constructing a
meta-ontology m(O) containing facts corresponding to the annotations in
O plus facts corresponding to the structure of the axioms in O.

One could envision a stripped-down version that doesn't include all of
the last bit - only individuals corresponding to each axiom in O.

It seems to me that the two-file solution has all the machinery of this
stripped-down version, plus the complications involved with having two

There are some "extras" that would be useful to have in this proposal,
including the ability to put arbitrary axioms into m(O).

> -Alan


Received on Wednesday, 16 July 2008 21:12:51 UTC