Re: LC responses 28, 48 & 58

From: "Michael Schneider" <schneid@fzi.de>
Subject: RE: LC responses 28, 48 & 58
Date: Tue, 10 Mar 2009 23:48:41 +0100

> Hi Ian!
> 
>>-----Original Message-----
>>From: public-owl-wg-request@w3.org [mailto:public-owl-wg-request@w3.org]
>>On Behalf Of Ian Horrocks
>>Sent: Saturday, March 07, 2009 6:50 PM
>>To: W3C OWL Working Group
>>Subject: LC responses 28, 48 & 58
>>
>>I drafted them. They all depend on the agreed presentation changes
>>and probably shouldn't be sent until those are completed.
>>
>>Ian
> 
> In the proposed answer to LC28
> 
>   <http://www.w3.org/2007/OWL/wiki/LC_Responses/FH2>
> 
> it is stated:
> 
> [[
> OWL 2 separates syntax from semantics, and that OWL 2 Full, 
> DL, QL, EL and RL are all refer to syntactic variants, 
> ]]
> 
> Frankly, this makes no sense to me. OWL 2 Full is certainly not a "syntactic
> variant", just as OWL 1 Full hasn't been.

OWL 2 Full is all ontologies / all RDF graphs.  A syntactic variant.
This matches the wording in the last paragraph of Section 2.3 of the
Document Overview but not that earlier in the Section.  I have proposed
changes to the Document Overview in my next message.

> In the OWL 1 Full spec, there existed semantic-related terms like "OWL Full
> interpretation" and "OWL Full entails". And OWL Full was characterized as
> follows in a semantic way:
>  
> <http://www.w3.org/TR/owl-semantics/rdfs.html#5.3>
> [[
> OWL Full augments the common conditions with conditions 
> that force the parts of the OWL universe 
> to be the same as their analogues in RDF.
> [...]
> ]]
> 

And, as Ian says, this story is being changed slightly.

> "OWL 2 Full" exclusively to mean the /semantics/. 

I argue against this.

I'm quite willing to abuse the notation and let OWL 2 Full mean
ontologies under the RDF-Based Semantics as well as just a syntax, just
as I would let OWL 2 DL mean ontologies that meet the syntactic
characterisation of OWL 2 DL under the Direct Semantics as well as just
a syntax.  

Note that part of the OWL 2 DL syntactic conditions have been chosen
only to allow for mapping into and out of RDF - these conditions are not
necessary to achieve the semantic and computational benefits of OWL 2
DL.  

> But Jonathan Rees had a comment on this:
> 
> http://lists.w3.org/Archives/Public/public-owl-comments/2009Jan/0068.html
> [[
> And are you sure that you want "OWL 2 Full" to be the name of a semantics?
> That seems OK to me, but it's sort of weird.  In common use I think it
> will be taken to mean a language consisting of a combination of syntax
> (RDF in any of its serializations) and
> semantics (conditions on interpretation of the OWL 2 vocabulary).
> ]]
> 
> This sounds reasonable to me, so I am strongly inclined to follow this
> comment. The term "OWL 2 Full" would then mean the whole language. But not
> the syntax alone. This would make no sense to me, because the syntax of OWL
> 2 Full is RDF, just as for OWL 1 Full and RDFS.

Well, I would argue that the true language of OWL 2 Full is the
Structural Specification.  The RDF serialisation is just something that
fits better into the current preferred Semantic Web story.

> Best,
> Michael

peter

Received on Tuesday, 10 March 2009 23:59:51 UTC