- From: Olaf Hartig <olaf.hartig@liu.se>
- Date: Fri, 22 Jan 2021 15:29:28 +0100
- To: public-rdf-star@w3.org
On fredag 22 januari 2021 kl. 13:13:55 CET thomas lörtsch wrote: > [...] > > Given this understanding, you may indicate the cases in which you want to > > use referential transparency on top of a referential opacity semantics by > > using specific properties that you introduce for this purpose. For > > instance, you may introduce a property denoted by the URI ex:statedBy and > > define that referential transparency can be used for nested triples that > > have this property in their predicate position. This way, related to your > > example, if you have a nested triple > > > > <<:cars :are :bad>> ex:statedBy :Alice > > > > you can derive the following triple. > > > > <<:automobiles :are :bad>> ex:statedBy :Alice > > > > So, while the semantics of RDF* adopts referential opacity, you can build > > on it and define cases in which you want to have referential > > transparency. > > But doesn’t this mean that in every case that you want to comment on a > triple with referential transparency you have to define a new property with > those specific semantics? I don't see why that would be necessary. Once I have introduced a property such as ex:statedBy (for which I have defined that referential-transparency inferences can be made for nested triples that have this property as their predicate), then I can use this property for any embedded triple. > That would seem like an outrageous demand to me. > > And even then: how would you define such a property? It probably should be a > subproperty of the property that you intend to use. No, I don't think so. However, I have a bit of trouble responding to this sentence because I am not certain what you mean by "the property that you intend to use." From my reading of your initial example, you wanted the property ex:statedBy to have a meaning that allows for referential-transparency inferences. So, if you simply define it to have this meaning, then it is the property that was intended to be used, isn't it? Best, Olaf > That seems to need a > new property like > > rdf*:isSubpropertyWithOpaqueSemanticsOf > > or even > > rdf*:isSubpropertyWithOpaqueSemanticsInDomainOf > rdf*:isSubpropertyWithOpaqueSemanticsInRangeOf > rdf*:isSubpropertyWithOpaqueSemanticsInDomainAndRangeOf > > as different embedded triples in subject and object position might have > different semantics. So you’d get three subproperties per any property from > any established vocabulary, right? Maybe not *all* of them but certainly > not a few in between. > > If this is indeed your proposal then I think you’ll have to come up with > something better. Or please explain what you meant instead. > > Thomas > > > Best, > > Olaf > > > > On torsdag 21 januari 2021 kl. 13:40:56 CET thomas lörtsch wrote: > >> [I hope I’m using the right terminology in the right way. Advice is > >> welcome.] > >> > >> The proposed semantics defines that the embedded triple refers to a > >> triple > >> on the syntactic level, not in the realm of interpretation. In defense of > >> this rather peculiar arrangement Pierre-Antoine and Dörthe argued that > >> going from the syntactic to the interpreted triple is always possible > >> whereas the other way round it is not: once a triple is part of the > >> interpretation we can not know what its original syntactic structure was. > >> That’s true (at least in any normal setup) but let's assume I’d like to > >> annotate not the syntactic triple but the interpreted triple. What would > >> I > >> actually have to do to construct a reference to an interpreted triple > >> from > >> an RDF* embedded triple? > >> > >> > >> Lets for example assume someone published the triple > >> > >> :cars :are :bad . > >> > >> As he published that statement on the semantic web we can assume that his > >> intend was to refer not only to :cars but just as well to :automobiles, > >> > >> :voitures etc. Now if we want to comment on that general interpretation > >> :of > >> > >> this statement, irrespective of the concrete vocabulary used, > >> irrespective > >> of any syntactic specifics, how would we do that? The proposed semantics > >> of > >> > >> << :cars :are :bad >> :a :disputedClaim . > >> > >> doesn’t cover this very common case as the embedded triple only refers to > >> that very specific syntactic form. From this RDF* statement we couldn’t > >> infer that > >> > >> << :automobiles :are :bad >> :a :disputedClaim . > >> > >> even if we were using a reasonably complete mapping of car related > >> vocabiularies. Adding all those derivable embedded triples to the > >> database > >> is not a viable option as it would increase operational costs enormously. > >> We need a way to derive a reference to the interpreted triple from the > >> syntactic triple that the RDF* embedded triple represents. But how? > >> > >> > >> Thomas
Received on Friday, 22 January 2021 14:29:48 UTC