W3C home > Mailing lists > Public > public-owl-wg@w3.org > October 2007

Re: Comments on structural specification (was Re: document pubication schedule)

From: Jim Hendler <hendler@cs.rpi.edu>
Date: Mon, 22 Oct 2007 20:31:12 -0400
Message-Id: <7A56732D-4AA4-4C8E-91C9-88852E5DE64A@cs.rpi.edu>
Cc: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>, jjc@hpl.hp.com, public-owl-wg@w3.org
To: Jim Hendler <hendler@cs.rpi.edu>

(in the example below I obviously meant owl:inverse and not just  
inverse - sorry)

On Oct 22, 2007, at 6:18 PM, Jim Hendler wrote:

>
> Peter asks that we bring up comments on the documents proposed to  
> be moved - here's my major comments on the structural specification.
>
>
> 1 - Structural Specification.  I am not convinced this document  
> moves forward the use of OWL, and instead forces an entirely new  
> syntax on a community that is finally learning to use N3 and RDF as  
> OWL specs, which is also what most tools currently consume and  
> produce.  I think the drawings are quite useful, but I find the  
> syntax to be difficult to teach and to use as it is not the natural  
> thing for me the way it is for some people trained in this area.   
> It's not that I couldn't learn, but I question why, to learn to use  
> a Semantic Web language I have to learn yet another syntax.
>  I also object to some of the same things in this syntax that I  
> objected to when an attempt was made for OWL 1.0 to use the  
> "abstract syntax" normatively.
>   i.  While it is nice that there is a notion of locality in the  
> document, I think it a positive and desirable feature that OWL  
> documents can have properties and classes intermixed and partially  
> defined in many parts of a document.  The non-linear nature (for  
> lack of a better term) of RDF is a positive I don't want to lose
>  ii. The namespace issues that Jeremy mentions are quite blurred in  
> this document
>  iii. I think the document introduces many terms into the  
> structural definitions that may or may not end up having actual  
> vocabulary terms associated with them in the OWL/RDF that results.   
> This means that someone trying to learn OWL through this document  
> cannot understand easily by the end what is, and is not, in the  
> vocabulary.  For example, picking one of many at random, will  
> "owl:dataComplementOf" be in the set of terms we are recommending  
> or won't it? there are many other features that make it hard to  
> know what is actually being proposed as language structures and  
> what aren't
>  iv. Appendix A makes some strange claims like:
>
> "For example, one can assert the following axiom in OWL 1.0:
>
> ObjectProperty(hasPart inverse isPartOf) "
>
> which is not true - only the abstract syntax of OWL (not part of  
> the recommendation as a normative way to exchange OWL documents)  
> allows that - in OWL one would say (in N3, I really should do it in  
> proper RDF but this is faster:)
>
> :haspart a owl:ObjectProperty;
>    inverse :isPartOf.
>
> So I believe the document, without more explanation of what it is  
> about (i.e. is this a replacement for the Abstract Syntax or  
> something more) and without changes that make it clear what was and  
> was not in OWL 1.0 will confuse a large portion of OWL users and  
> require considerable effort and learning for those who have already  
> learned and use OWL regularly.
>
>  v. The use of authors, over editors, is somewhat at odds with the  
> use of these terms in the W3C (http://www.w3.org/2001/06/manual/ 
> #Editors)
>
> In short, I don't see the structural syntax being needed on the Rec  
> track without at least a significantly better explanation of its  
> use, its need, and its role in the new recommendations (i.e.  is it  
> a presentation syntax, is it the definition of new terms, is it the  
> abstract syntax for logical clarity.
>
>
>

"If we knew what we were doing, it wouldn't be called research, would  
it?." - Albert Einstein

Prof James Hendler				http://www.cs.rpi.edu/~hendler
Tetherless World Constellation Chair
Computer Science Dept
Rensselaer Polytechnic Institute, Troy NY 12180
Received on Tuesday, 23 October 2007 00:34:09 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 8 January 2008 14:13:26 GMT