- From: Pat Hayes <phayes@ihmc.us>
- Date: Fri, 7 May 2004 22:47:43 -0500
- To: Ian Horrocks <horrocks@cs.man.ac.uk>
- Cc: Stephen Rhoads <rhoadsnyc@mac.com>, www-rdf-logic@w3.org
>For those who didn't follow the debates on the webont mailing list, I >should perhaps draw your attention to the sad history of Pat's morbid >obsession with DLs. I had hoped that having recognised the problem [1] >(the first and hardest step) he would by now be well on the road to >recovery. Sadly, it would appear that this is not the case. In fact >this is not Pat's first relapse [2], so perhaps we shouldn't be >surprised. > >Ian > >[1] http://lists.w3.org/Archives/Public/www-webont-wg/2002Sep/0411.html >[2] http://lists.w3.org/Archives/Public/www-webont-wg/2002Dec/0092.html Perhaps also not uncharacteristically, Ian manages to simultaneously be insulting, offensively ad-hominem and to mislead the unwary reader. The acknowledgement in [1] was to a completely unrelated misunderstanding arising in part from my reaction to an extended series of memoranda claiming to show that (what is now called) OWL-Full was impossible, by a specious reference to the set-theoretic paradoxes, but also in part, I concede, from my own ignorance of DL metatheory at that time. The opinions I expressed in [2] are unrelated to [1] , are not a 'relapse' - to acknowledge that DLs are a subset of FOL is not to endorse the basing of the entire SW effort on that subset - and I still hold them, and will continue to hold them. I won't react to such jibes in future, but the record should be set straight. Pat > >On May 7, Pat Hayes writes: >> >> >I realize that everyone is probably beat from that "Classes as >> >Values" discussion in the SWBP, but ... no thoughts on this? >> > >> >Would it be unthinkable to create a subPropertyOf rdf:type? >> >> Its explicitly forbidden in OWL-DL by edict of the DL police, but it >> makes perfect semantic sense and could be done in OWL-Full. On the >> other hand, why not just use rdf:type? What do you gain from the >> explicit subpropertying? >> >> If you thought to sneak past the DL syntax restrictions, forget it. >> The DL police have already thought of all the tricks you could use >> and blocked all the exits. >> >> Pat >> >> >Something like ... >> > >> ><owl:ObjectProperty rdf:ID="hasGenre"> >> > <rdfs:subPropertyOf rdf:resource="&rdf;type"/> >> ></owl:ObjectProperty> >> > >> ><ex:Song rdf:ID="PurpleHaze"> >> > <ex:hasGenre rdf:resource="&ex;ClassRockMusic"/> >> ></ex:Song> >> > >> >Thus, the Individual "PurpleHaze" is an instance of both Song and >> >ClassicRockMusic. >> > >> >Note that the intent is state class membership, not to say that the >> >"subject" of the Song is a concept denoted by a Class (as in the >> >"Classes as Values" paper). >> > >> >--- Stephen >> > >> > >> >On Apr 24, 2004, at 4:50 PM, Stephen Rhoads wrote: >> > >> >> >> >>Folks, >> >> >> >>There are various parts of my (Media Publishing and Distribtuion) >> >>ontology where I would like to avoid the requirement of "multiple >> >>typing". The objective here is to simplify the ontology and user >> >>interfaces which employ it. >> >> >> >>A user of the ontology should be able to simply declare an >> >>Individual to be a Song, Album, Movie, MovieSeries, >> >>TelevisionProgram, TelevisionSeries, RadioProgram or RadioSeries. >> >>Other important class membership should be inferred by property >> >>values. A TelevisionSeries, for example, could have >> >>"hasSeriesType" of "SeasonalSeries" and thus be a member of that >> >>Class. A Movie could have "hasGenre" of "Drama" and thus be a >> >>Drama. >> >> >> >>The problem is that I can't see how to model this without landing >> >>in OWL Full. Take the following example: >> >> >> >>A sample Class hierarchy: >> >> >> >>Music >> >> ElectronicMusic >> >> PopMusic >> >> RockMusic >> >> ClassicRockMusic >> >> GlamRockMusic >> >> GrungeRockMusic >> >> >> >>And sample Class description: >> >> >> >><owl:Class rdf:ID="ClassicRockMusic"> >> >> <rdfs:subClassOf rdf:resource="#RockMusic"/> >> >> <owl:equivalentClass> >> >> <owl:Restriction> >> >> <owl:onProperty rdf:resource="#hasGenre"/> > > >> <owl:hasValue rdf:resource="#ClassicRockMusic"/> >> >> </owl:Restriction> >> >> </owl:equivalentClass> >> >></owl:Class> >> >> >> >>In other words, if the Individual (a Song or Album) hasGenre >> >>ClassicRockMusic, then it *is* ClassicRockMusic (or at least a >> >>member of a Restriction Class with the same class extension). But >> >>(I think) this puts the ontology into OWL Full because >> >>ClassicRockMusic is being treated as both a Class and an Individual >> >>(I can confirm that Racer will not accept the ontology from Protege >> >>because it is "not in OWL DL"). >> >> >> >>Thoughts? Solutions? >> >> >> >>--- Stephen >> >> >> -- >> --------------------------------------------------------------------- >> IHMC (850)434 8903 or (650)494 3973 home >> 40 South Alcaniz St. (850)202 4416 office >> Pensacola (850)202 4440 fax >> FL 32501 (850)291 0667 cell >> phayes@ihmc.us http://www.ihmc.us/users/phayes >> -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ihmc.us http://www.ihmc.us/users/phayes
Received on Friday, 7 May 2004 23:47:45 UTC