- From: Jim Hendler <hendler@cs.rpi.edu>
- Date: Mon, 22 Oct 2007 18:18:03 -0400
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: jjc@hpl.hp.com, public-owl-wg@w3.org
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.
Received on Monday, 22 October 2007 22:20:47 UTC