- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Wed, 30 Jul 2008 03:07:25 +0100
- To: Bijan Parsia <bparsia@cs.man.ac.uk>
- Cc: Semantic Web <semantic-web@w3.org>
Bijan, Wow, seems like I really pushed the wrong buttons! My intention *was* to be controversial, but not *that* controversial. I didn't mean this as a personal attack on you. I meant it as an attack against a specific technical decision made in the design of OWL. It is evident that I crossed a line here and for that I apologize, and I accept the blame for the temporary deterioration of the thread. I think we agree on two facts: 1. Creating subproperties of rdfs:label puts ontologies into OWL DL, which is undesirable for OWL reasoners. 2. Creating subproperties of rdfs:label enables RDF consumers like Tabulator to do some useful presentational things. So there's a real conflict. We don't want to force ontology authors to pick sides, so it would be good to resolve it somehow. There are two proposals: a) Accept that creating subproperties of rdfs:label was a bad idea, and change the RDF browsers and existing ontologies to use either a different property or a different mechanism, b) Accept that subproperties of rdfs:label are a fact of life, and change the OWL reasoners to automatically clean up those parts that are outside of OWL DL. To me it is not self-evident that a) is the correct answer. I would prefer b). I admittedly have not much clue about OWL, so please forgive me if I display my ignorance once more, but wouldn't it be a nice feature anyway if OWL reasoners were able to automatically clean up ontologies to the desired level of Full, DL, or Lite? Would that be a workable alternative, instead of designing a new mechanism for presentational annotations? Any opinions appreciated. Richard On 30 Jul 2008, at 00:28, Bijan Parsia wrote: > On Jul 29, 2008, at 8:44 PM, Richard Cyganiak wrote: > >> On 29 Jul 2008, at 15:23, Bijan Parsia wrote: >> >>> On 29 Jul 2008, at 15:08, Tim Berners-Lee wrote: >>> >>>> Making something like pub:name a subProperty of rdfs:label is >>>> essential >>>> for the Tabulator for example to know it can use names as labels >>>> in the UI. So please do it >>> >>> I would suggest that Tabulator find a better way. E.g., something >>> Fresnelish. > > For many reasons. I.e., I would recommend this even if > subpropertying rdfs:label becomes legit OWL DL. > >> Let me see. > > Try *thinking* next time. > >> 1. The RDF working group defines RDF and RDFS, including the useful >> utility properties rdfs:label, rdfs:comment, rdfs:seeAlso and >> rdfs:isDefinedBy. > > Er...to say that they "defined" them is stretching things a bit. E.g., > > """(rdfs:comment, rdfs:seeAlso, rdfs:isDefinedBy and rdfs:label are > included here because some constraints which apply to their use can > be stated using rdfs:domain, rdfs:range and rdfs:subPropertyOf. > Other than this, the formal semantics does not assign them any > particular meanings.)""" > >> 2. RDF people start to use these properties in conformance with the >> specs. > > Also stretching things a bit. > >> 3. While defining OWL-DL, the OWL WG introduces rather arbitrary >> restriction on all these properties. > > It's not actually arbitrary per se, but I do understand that > technical considerations are a lost cause on you. > >> 4. OWL people ask RDF people to stop subclassing these properties >> in order to meet the restrictions imposed by OWL-DL. > > Do whatever you want. > >> This doesn't make any sense to me. > > Many things don't, I see. I notice you elided the fact that you have > a rather ridiculously constrained notion of the "open web". There's > no *need* to be hostile, after all. (And yes, you started the tone > in the gutter in the face of non-guttered tone.) > >> The OWL WG blundered when they redeclared these properties as >> annotation properties. > > That part is quite sensible, actually. The design of RDF is > problematic in several ways not least in mixing domain modeling and > annotative stuff. > > I wouldn't be surprised if these choices don't affect you. Good for > you. I even understand that you don't care about people for whom it > matters. Also good for you. > >> [snip] >>>> Presumably OWL DL systems can be built to ignore the >>>> rdfs:subClassOf fact when they do OWL-DL reasoning on the data. >> >> +1. You broke it, you fix it. > > > Thanks for playing. > > Cheers, > Bijan.
Received on Wednesday, 30 July 2008 02:08:09 UTC