Re: interoperability (was Re: isolating shapes in named graphs)

I am puzzled about the purpose of this topic here. What are we trying to 
achieve?

There are tons of statements that I disagree with here in this thread. 
In particular we should not cloud our design of a new language by 
situations that were created with open world/reasoning languages like 
OWL and RDF Schema. The fact that those languages have been there first 
does not mean that they are the only interpretation of semantic web 
technology. Property reuse across ontologies was often driven by data 
merging use cases (via rdfs:domain inferencing). If you take RDFS/OWL 
inferencing out (which we hopefully do), then the desire to reuse 
properties is much less relevant.

In the end, the shapes language should allow designers to chose how they 
publish their constraints, and there are already plenty of techniques to 
either work around global definitions (e.g. redefining terms), or 
separate constraints from class/property definitions into different 
named graphs. So I am not sure what this discussion is about here, and 
how it would influence our technology choices.

I also want to highlight that we are not just talking about "the 
Semantic Web" as a whole. I believe most successful applications of this 
technology are actually inside of closed company networks, where strict 
semantic contracts can and have to be enforced.

Holger


On 11/27/2014 8:36, Eric Prud'hommeaux wrote:
> * Peter F. Patel-Schneider <pfpschneider@gmail.com> [2014-11-26 07:20-0800]
>> On 11/26/2014 05:46 AM, Eric Prud'hommeaux wrote:
>>> * Peter F. Patel-Schneider <pfpschneider@gmail.com> [2014-11-26 05:11-0800]
>>>> One usually uses an external URI, like foaf:mbox, because one wants
>>>> interoperability of meaning.  However, I do not believe that
>>>> complete interoperability of URI meaning should be mandated.  I also
>>>> do not believe that complete interoperability of URI meaning is
>>>> possible.
>>>>
>>>> Further, I believe that effective interoperability can be achieved
>>>> without mandating use of defining definitions.  For example, I may
>>>> decide that I don't want to use the "static" part of the definition
>>>> of foaf:mbox. Interoperability should remain for most purposes.
>>>>
>>>> Particular commmunities can, if they want,  require stronger
>>>> conditions on shared meaning.  Perhaps it would be possible to set
>>>> up a community that achieves complete interoperability of meaning.
>>>> However, I very strongly believe that "the web" cannot be such a
>>>> community, and thus that W3C recommendations should never mandate
>>>> it.
>>> It sounds like if I'm not feeling lucky, I should never consume data
>> >from anyone with whom I've not written up some contract. What would
>>> that contract say? "I agree to use the vocabularies according to their
>>> documented semantics. I will not use terms if I don't understand their
>>> semantics."
>> I don't think that you have to have a direct contract with that
>> other party. There could be some out-of-band information about that
>> other party, for example that they are a participant in some
>> community.  There could also be information in documents, such as
>> the use of logical properties, like rdf:type or owl:imports.  Sure a
>> particularly perverse player could use these properties differently
>> than you expect, either intentionally or inadvertently, but using
>> logical properties in a non-standard fashion is something that
>> should only be done, in my view, with great trepidation.
>>
>> (Of course, I'm actually going against web practice here somewhat.
>> There are many situations where logical properties are not used
>> correctly.  Consider owl:sameAs, for example.)
>>
>>>> Merging data from different sources can be problematic even if the
>>>> use of defining definitions is mandated.  Data can be incorrect,
>>>> after all.
>>> I suspect you are being a bit provocative here,
>> Not at all, I've held this position from the very beginning of my
>> involvement with the semantic web.  I and others have forcefully
>> argued it at various meetings, and have affected W3C recommendations
>> thereby.
>>
>>> and I'm playing along
>>> nicely. Surely we needn't jettison this fine bathwater just because
>>> it's slightly sullied by a baby. It's quite practical to say that I
>>> will respect, or at least not contradict, the properties of foaf:mbox
>>> even if there's an assertion elsewhere in that ontology that the moon
>>> is a subclass of Things made of green cheese. What's the actual
>>> screw-case if I use <http://dbpedia.org/resource/Moon>?
>> Well, you do commit to lots of unusual things in this case.  For
>> starters, there are several minimum and maximum temperatures.
>>
>> If you commit to the DBpedia ontology you get a number of unusual
>> consequences, like Berlin being a mountain and Lambeau Field being a
>> city. You also commit to unusual definitions of many categories.
>> For example, all windmills are buildings, all libraries are
>> educational institutions, chess players are athletes, saints are
>> clerics, baronets are british royalty, professors are scientists.
> OK, let's take a fairly pessimal case and utter
>    dbp:Deep_Blue :wonAgainst dbp:Garry_Kasparov .
> and this peculiarly entails that Deep Blue is a dbp:Athlete.
>    dbp:Deep_Blue a dbp:Athlete .
>
> No one will have any problems consuming our little assertion unless
> their logic somehow interacts with the wikipedia hierarchy, in which
> case they're already marrying an ontology with known bugs.
>
>
>> I care about this sort of thing because I want to use the
>> consequences of web information in my systems.  I don't want to have
>> to commit to too much, however.  I also want to be able to commit to
>> some things and see when the sources that I do use have committed to
>> other things.  I certainly don't want to have to commit to the
>> entire web to use any of it.
>>
>> peter

Received on Wednesday, 26 November 2014 23:05:41 UTC