Re: isolating shapes in named graphs

On 11/26/2014 02:45 AM, Eric Prud'hommeaux wrote:
> * Peter F. Patel-Schneider <> [2014-11-26 02:23-0800]
>> On 11/25/2014 10:22 PM, Eric Prud'hommeaux wrote:
>>> * Peter F. Patel-Schneider <> [2014-11-25 16:20-0800]
>>>> On 11/25/2014 02:14 PM, Eric Prud'hommeaux wrote:
>>>>> * Holger Knublauch <> [2014-11-19 22:36+1000]
>>>>>>                                      For the majority of use cases
>>>>>> you would end up with Shape objects that are mirroring classes,
>>>>> I disagree that the majority of shapes would be global invariants.
>>>>> But regardless, the fact that we don't want to write off the other use
>>>>> cases implies that we must not require a model which forces one to
>>>>> retract one schema when looking at another when both should be associated
>>>>> with particular interfaces.
>>>> What does "global invariant" mean here?
>>>> There is no way that constraints can be truly global, i.e., that
>>>> every use of RDF has to include them all.  I don't see anyone
>>>> arguing that the mere use of a class requires the use of all
>>>> constraints associated with that class, which perhaps could be
>>>> considered to be akin to a global invariant.  All other setups for
>>>> constraints appear to be situational, i.e., not global.
>>> Three messages "up" in this thread, I was arguing just that. See
>>> <> (attached).
>>> I agree re "situational". As a counter example, the FOAF ontology
>>> *could* say that foaf:mbox had a cardinality of one, but that would
>>> needlessly restrict its usage. (At TPAC, Tantek beat me up about
>>> having cardinalities attached to vocabulary definitions. After a sound
>>> drubbing, I managed to explain that he was beating up the wrong guy.)
>>>> peter
>> I don't see in that message that you are arguing for either true
>> globality, that all users of RDF commit to all constraints, or even
>> mention globality, that all users of something like foaf:mailbox
>> commit to all constraints that mention foaf:mailbox.
>> Note that I'm not stating that no one has argued that constraints
>> that are part of an ontology (if this is possible) must be in force
>> for all users of that ontology.  I would even argue for this.  I'm
>> not even stating that no one has argued constraints that are part of
>> an ontology (if this is possible) must be in force for all users of
>> vocabulary defined in that ontology.  I, however, argue against
>> this, just like I argue against vocabulary mention requiring
>> ontology use.
> If I don't owl:includes foaf:, can I use foaf:mbox in a way that is
> specifically inconsistent with its definition in FOAF, e.g. having it
> not being an IFP, possibly representing my shoe size?


> If so, where do
> we get interop?

We don't, and I don't feel that there is any need to mandate interoperability 
by simple vocabulary mention.  Interoperability is a desirable goal, of 
course, and there are many situations where it should be in force.  However, 
there are lots of situations where interoperability fails.  (The DBpedia 
ontology shows one failure mode.)

> If not, is there a boundary around foaf:box ?p ?o for
> which I am responsible when I utter foaf:mbox?

No.  You may choose to ignore the defining document for foaf:mbox.  You do so 
at your  peril, of course.  (I wonder how many uses of foaf:mbox are 
incompatible with its definition, particularly the static inverse functional 
property aspect.)

>> Why do I argue against vocabulary mention requiring ontology use?
>> Consider DBpedia.  The DBpedia ontology has many problems, including
>> incorrect subClassOf relationships.  It should be possible to use
>> the DBpedia class vocabulary, and even the entire DBpedia graph,
>> with committing to the DBpedia ontology.
> Is Danbri mischievous enough to add a deliberate inconsistency to test
> this issue? IIRC, he started FOAF 'cause said "but RDF could be used
> to track everyone. That's horrible; now what would that look like?"

Well FOAF is specified using certain OWL properties.  Does that mean that all 
users of FOAF have to abide by the OWL semantics?  Does the use of 
rdfs:subClassOf mandate using the RDFS semantics?  Does the use of rdf:type 
mandate using the RDF semantics?


Received on Wednesday, 26 November 2014 11:15:40 UTC