[LC response] To Thomas Lörtsch Re: comments on the owl 2 last call

Dear Thomas,

Thank you for your comment
     <http://lists.w3.org/Archives/Public/public-owl-comments/2009May/0024.html>
on the OWL 2 Web Ontology Language last call drafts.

Primer:

The primer has undergone considerable revision, and is about to be
released as a "Last Call" working draft. A primer is, by its very
nature, susceptible to being pulled in very many different
directions. Producing a primer that satisfies everyone's needs would not
be possible given the Working Group's resource constraints, and is
probably not possible at all. The Working Group therefore decided to
focus on producing a short language primer. We expect that additional
Primer-like documents will be produced by third parties, as has been the
case with OWL. 

Other Introductory Documents:

The remit of the Working group is primarily one of language
specification, hence the technical nature of most documents. The Working
Group is already struggling with document overload and resource
limits. The Working Group feels that the Primer and Quick Reference
Guide provide an adequate introduction to OWL 2, and believes that it is
appropriate for additional user-facing documents to be produced outside
the Working Group. 

Syntactic Variations:

One reason for the various syntaxes for OWL is that the "main" syntax
(RDF/XML) is difficult to use, and in particular difficult to use for
specification. The Functional syntax serves just this purpose: precise
specification of the constructs of the language and their semantics. The
other syntaxes satisfy other requirements, in particular compatibility
with XML tool chains (the XML syntax) and ease of reading/writing (the
Manchester syntax). Developing (syntax conversion) tools is outside the
remit of the Working Group. Such tools are, however, already being
developed by third parties; see, for example, the OWL API
<http://owlapi.sourceforge.net/>. 

rdf:XMLLiteral:

This datatype is listed as at-risk because the current known
implementations for OWL 2 or variants thereof may not fully implement
this feature. The Working Group expects that during the Candidate
Recommentation phase (coming shortly), implementations will indeed be
produced for rdf:XMLLiteral and its "at risk" status will be removed. 

RDF reification vocabulary:

There are technical reasons not to use the RDF reification vocabulary,
having to do with wanting an even weaker formal semantics, and
perception reasons not to use the RDF reification vocabulary, having to
do with diverging intended meanings for the RDF reification
vocabulary. Therefore, the Working Group is unwilling to use the RDF
reification vocabulary. 

New namespace:

The Working Group feels that OWL 2 is the "new" OWL, and OWL 2 is
backwards compatible with OWL. There are also significant costs to
having a separate namespace for OWL 2 (for example, writing qualified
cardinality restrictions would be problematical). For these reasons the
Working Group decided that OWL 2 should not have a new namespace. 

Please acknowledge receipt of this email to
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suffice). In your acknowledgment please let us know whether or not you
are satisfied with the working group's response to your comment. 

Regards,
Peter F. Patel-Schneider
on behalf of the W3C OWL Working Group

Received on Monday, 18 May 2009 12:41:09 UTC