ISSUE: OWL-DL compatibility

In today's telecon I was asked to reanimate the issue of OWL compatibility,
which was discussed 1 month ago.

Here is the relevant message:

http://lists.w3.org/Archives/Public/public-rif-wg/2009Sep/0017.html

The current situation is a bug, IMO. If it isn't a bug then at least that part
of the document is very unsatisfactory and obscure. Jos proposed 3 solutions:

1- leave things as they are, assuming that # and ## are not of interest
   to users of RIF-OWL DL combinations
2- explain the use of # and ## in the document (this would certainly not
   be a substantive change, so we should not run into procedural problems)
3- define the semantics of # and ## in RIF-OWL DL combinations in a
   similar fashion as in RIF-RDF combinations: a one-to-one correspondence
   between # and OWL class membership statements and implication between ##
   and OWL subclassing.

The easiest for him would be to do nothing (1), thus leaving things
unsatisfactory and obscure. His next choice is (3), which is also my choice and
the "right thing to do."  (3) stretches things a little, but it can be argued
that it is a simple fix.

Solution (2) is more work. It fixes the obscurity aspect, not the
unsatisfactory aspect of the definitions. So, (3) seems like the best way to
proceed.

Solution (3) still leaves some problems, which are unrelated to the above
issues. In the current semantics, subclassing in RIF implies subclassing in
OWL/RDF, but not vice versa.

In this regard, I would like to point to my follow-up message
http://lists.w3.org/Archives/Public/public-rif-wg/2009Sep/0019.html
Here I proposed a stronger semantics, which fixes this non-entailment problem.

This would certainly be a substantive change semantically (although not
significant textually). If we don't have the energy to do it this time,
maybe for RIF 1.1.

michael

Received on Tuesday, 13 October 2009 21:56:39 UTC