Re: Handling multiple rdfs:ranges

On Tue, Feb 23, 2016, at 20:05, Antoine Zimmermann wrote:
> Reto,
> 
> 
> On 23/02/2016 18:12, Reto Gmür wrote:
> >
> >
> > On Tue, Feb 23, 2016, at 17:41, Peter F. Patel-Schneider wrote:
> >> On 02/23/2016 08:24 AM, Reto Gmür wrote:
> >>> On Tue, Feb 23, 2016, at 17:05, Peter F. Patel-Schneider wrote:
> >>>> On 02/23/2016 07:31 AM, Reto Gmür wrote:
> >>>>> [...]
> >>>>>
> >>>>> Granted, the semantics of :rangeIncludes are very weak (under OWA) but
> >>>>> the fact that you can create contradictions with it shows that it's not
> >>>>> completely meaningless.
> >>>>>
> >>>>> ex:prop1 s:rangeIncludes :Cat .
> >>>>> :Cat owl:disjointWith :Dog .
> >>>>> ex:prop1 owl:range :Dog .
> >>>>>
> >>>>> The above graph evaluates to false in every possible world, this is not
> >>>>> the case if you omit any of the 3 triples, this shows that
> >>>>> `s:rangeIncludes` is not a meaningless decoration.
> >>>>>
> >>>>> Reto
> >>>>
> >>>> I don't think that this follows from the semantics of :rangeIncludes,
> >>>> even if
> >>>> you augment schema.org semantics with disjointness.
> >>>
> >>> In the example I also used "owl:range" to create what I thought is a
> >>> contradiction.
> >>
> >> OK, but I saw that.  (I actually missed that there are no values for
> >> ex:prop1.
> >>   Without any such values you don't get a contradiction even if you made
> >>   both
> >> of the ranges be OWL ranges, and used OWL semantics.)
> > You're right, forgot [] ex:prop1 [].
> 
> Even with this, there is no inconsistency. The above statement plus the 
> other statements you mentioned before say that there is something in 
> relation with another thing of type Dog, and not of type Cat, via 
> property ex:prop1. Where is the inconsistency?

You're right, adding the statement using the property doesn't make it
inconsistent as s:rangeIncludes doesn't determines the type of the
object.

My interpretation of s:rangeIncludes is that the extension of the
intersection of the rdfs:ranges must include the extension of
s:rangeIncludes. I think this is consistent with the definition from
https://schema.org/rangeIncludes as long as the term "expected" is
narrowly interpreted as "rationally expected" or as "possible". 

Reto

Received on Wednesday, 24 February 2016 16:25:15 UTC