Re: DOCUMENT: Layering document review (was Re: UPDATE: status of longer version of layering document)

At 10:12 AM +0100 2/14/02, Frank van Harmelen wrote:
>Jim Hendler wrote:
>
>>  Umm, I think the *next* step is to get some people working on some
>>  specific proposals - not to have a general discussion of approach, we
>>  need to have specific proposals on the table to discuss and move
>>  through.
>
>Jim,
>
>I think we are already close to this:
>
>The layering document lays out 4 options.
>
>1.Same-syntax semantic extension:
>2.Syntax and semantic extension
>3.Same-syntax, but diverging semantics
>4.Differing syntax and semantics
>
>Each of options 2-4 could be realised without further ado,
>
>Option 2 would lead to "extraordinarily-complex and difficult 
>patterns of reasoning",
>so is out.
>
>I get the impression option 4 is not really serious (it basically 
>ignores RDFS).
>
>These leaves 1 and 3.
>
>Option 3 has the nice feature that we can use RDF to reason about OWL syntax.
>
>option 1 is very nice but could only be chosen if at least one of 
>the following fixes was made to RDF(S):
>1a move rdf:type to the meta-theory
>1b stratify RDFS
>1c allow for un-asserted triples in RDF
>(and perhaps 1a and 1b are the same if someone could explain it to me)
>
>Looks like the next steps would be to get a sounding from RDF Core on 1a-c.
>If these are all out, we now where we stand.
>If at least one of these could be in, we have to choose between 1 and 3.
>
>Frank.
>    ----

I keep hearing one person at a time talk about how things are obvious 
- but we have another 40+ people to convince (first - after that 
another N where N is large if we want our recommendation passed). 
I'd sure like to see some of the rest of the WG folks commentign and 
adding their thoughts.  For example, I think "extraordinarily-complex 
and difficult patterns of reasoning" is a terribly unenlightening 
phrase especially as I am holding a charter that says 2 (which is 
what DAML+OIL does) is our default, and I've yet to see this group 
reaching agreement that any of 1,3, or 4 is a technical improvement.

The charter is not a funky document to be ignored - it is what the 
W3C membership authorized us spending their money on, and Guus and I 
have to show that whatever this WG produces agrees w/our charter.  I 
simply don't see consensus emerging that there is soemthign seriously 
wrong with DAML+OIL and that we want to change it drastically -- and 
thus either someone needs to convince the WG (and thus me) that this 
would not be a drastic change, or else to convince the group that the 
drastic change is needed.

Peter and Dieter's document motivates some sort of change, but how 
much and in what direction is a crticial thing for our group.

Thus, I think the messages you and Peter are sending about possible 
approaches are valuable and enlightening, but I don't see that we are 
as close to a solution - in terms of reaching consensus in a 
practical manner - as we need to be.
  -JH

-- 
Professor James Hendler				  hendler@cs.umd.edu
Director, Semantic Web and Agent Technologies	  301-405-2696
Maryland Information and Network Dynamics Lab.	  301-405-6707 (Fax)
AV Williams Building, Univ of Maryland		  College Park, MD 20742
http://www.cs.umd.edu/users/hendler

Received on Wednesday, 13 February 2002 18:11:55 UTC