- From: Jeff Heflin <heflin@cse.lehigh.edu>
- Date: Thu, 30 May 2002 11:33:56 -0400
- To: Deborah McGuinness <dlm@ksl.stanford.edu>
- CC: Webont <www-webont-wg@w3.org>
Deborah, It seems to me that by adding universal local range restrictions, existential local range restrictions, and local cardinality restrictions, that we are almost back at the full language again. As far as I can tell, the only thing left out is boolean combination of class expressions. If this is the case, then we have to consider whether there is really a point in having a compliance level 1. As a possible way forward, we should consider the motivation of trying to provide a language that tool suite developers can support more easily. Of course the problem here is that there are different implementor communities that have different ideas of what is "easy to support." I see potential implementor communities based around the following types of systems: 1) databases 2) description logic systems 3) logic programming (e.g., Prolog) 4) theorem proving Perhaps the thing to do is to figure out what features can be easily supported by each of these kind of systems and take the intersection. Since the language is evolving out of description logics, then we can probably assume everything in full-OWL is easy to do in description logic systems, and since FOL theorem provers are even more expressive, then we can probably assume that everything is easy in these systems as well. That leaves us with databases and logic programming. However, the database vendors capabilities may be too restrictive. Their systems probably most closely align with plain old RDF + datatypes. Thus, this leaves us with the logic programming community. I believe a large number of DAML team members are using some variation of logic programming, such as traiditional Prolog systems or the XSB system. We could ask them what parts of DAML+OIL they implement and then use this as our basis for a level 1 language. If we don't, then they are likely to create versions of the language that don't meet the compliance level, defeating the whole point of compliance levels. Jeff Deborah McGuinness wrote: > > I have made an update to the compliance document. > > 1 - I have not changed the name but will be happy to if we like owl lite > or something else better. > > 2 - I attempted to take feedback provided and incorporate the > non-contentious stuff. > > 3 - I attempted to take the contentious topics with broad interest - > namely local range restrictions, cardinality, and presentation style and > include my proposal. > > Note - I did NOT check this with the people who offered to help on this > document, so dont blame them- I deserve the flames. > > Ultimately I needed to balance the input and I felt that more sentiment > had come in that > this was too restrictive in that it would not meet the needs of too many > applications that > were the prime kinds of applications that needed more than RDF/S. > Thus, some would say that I went too far and violated the goal of > staying quite simple. > Some would say I didnt add enough. > > Bottom line - I included local range restrictions (global and > existential) and cardinality. > My solution to the issues with presentation is to get this document out > (wordsmithing as necessary if people do not think I have adequately > characterized the limitations we need to live within for RDF) > and then also write a presentation of the language as a limited form of > the full language. > I will do that next once we have agreement that at least no one is so > offended by this proposal that they need to quit the webont effort. > Hopefully we will have more agreement than that, but if that is all that > can be achieved, then I will take that. > > Comments welcome. > > the document is in the same place: > http://www.ksl.stanford.edu/people/dlm/webont/compliance.html > > thanks for all the great feedback to date. > > Deborah > -- > Deborah L. McGuinness > Knowledge Systems Laboratory > Gates Computer Science Building, 2A Room 241 > Stanford University, Stanford, CA 94305-9020 > email: dlm@ksl.stanford.edu > URL: http://ksl.stanford.edu/people/dlm > (voice) 650 723 9770 (stanford fax) 650 725 5850 (computer fax) > 801 705 0941
Received on Thursday, 30 May 2002 11:34:37 UTC