- From: Deborah McGuinness <dlm@KSL.Stanford.EDU>
- Date: Sun, 07 Apr 2002 23:07:57 -0700
- To: Frank van Harmelen <Frank.van.Harmelen@cs.vu.nl>
- CC: www-webont-wg@w3.org
My main point of this message is to make a plea for a simple enough language in the simplest of our lite language(s). The reason for my plea is in talking to a number of users and potential users, I am consistently getting feedback that DAML+OIL is too hard to understand/hard to use. I think we should be making a lite layer with the goal of understandability and broad usage (this is inline with Frank's email below.) If we get clear on what the criteria should be for allowing a construct to be put into the lightest layer, then we will have an easier time making the choices. Right now, i believe the lite frame layer is too heavy. I would make this argument separately from making the argument for a certain number of layers. My strongest point is that the light layer should be simple enough to be used by the masses. Operationally I claim that means - frame syntax can be used - broadly used frame-like expressive power is included - represenational notions that are difficult to explain/use are reserved for heavier layers My second point/suggestion is to first observe that frame systems appear to have broad acceptability. Thus I fully support the notion that the light layer should have a frame feel. I would find it acceptable to have two frame layers - 1 - the light frame layer - this only has simple notions but still of course has more than rdfs 2 - the heavy frame layer - this contains many things that one can express in a frame syntax but includes some of the more difficult constructs. this includes things such as cardinalityq as an offer, I am willing to take co-editorship responsibility for getting a document out that is presumably the followon to the document at: http://www.cs.vu.nl/~frankh/spool/OWL-first-proposal/frame.html deborah Frank van Harmelen wrote: > There was some discussion at an earlier teleconf on what the deciding factor > was to put something in the "Lite" part of the proposed language. > > I argued that the "Lite" part was "simpler", without being very clear on what > "simpler" meant. > > A telephone conversation with Deb McGuinness prompted me to be more explicit > about this design goal of the "Lite" layer. (I'm not speaking for Peter or Ian > here...) > > Frank. > ---- > > The OWL Light subset was intended to be simpler than Full OWL in some > way. There was some discussion at the teleconf what "simpler" meant. > It means "conceptually simpler", > not "syntactically simpler", > not "computationally simpler". > > - CONCEPTUALLY SIMPLER. The goal was to make a subset of Full OWL > that was conceptually easy to understand by our target group, and that > made it easy to say things that users want to say often. > This is also the reason why OWL Light contains "shorthand notations" > for things that could already be said in longhand. The shorthands are > meant to make it easy to say and understand the things that people > want to say often. > > - SYNTACTICALLY SIMPLER: This was >*not*< the simplicity we were > striving for. In fact, I think it is unlikely that the OWL Light will > have a much simpler grammar than Full OWL. I think it will be > somewhat simpler through the lack of nested expressions (the > <description>'s in [1]), but not much. > > - COMPUTATIONALLY SIMPLER: Again, this was >*not*< the simplicity we were > striving for. Although OWL Light is in fact less expressive than Full > OWL, this was not our main driving force. > > [1] http://www.cs.vu.nl/~frankh/spool/OWL-first-proposal/ -- 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 Monday, 8 April 2002 02:08:47 UTC