Re: datasets mean their default graphs?

Eric, a late reply, sorry. 

On Jun 21, 2013, at 10:25 AM, Eric Prud'hommeaux wrote:

> * Pat Hayes <phayes@ihmc.us> [2013-06-21 09:52-0500]
>> OK, lets try to find a better way to word it. The point we need to get across is that a dataset can be treated just as an uninterpreted data structure, but *if* it is used to convey RDF content then at a minimum, it must be understood to be asserting its default graph. Sandro thinks, and I agree, that this is an essential condition to have in order to support vocabulary-based semantic extensions. 
> 
> I think we care more about how the consumer is interpreting the dataset than how the publisher intended it to be interpreted.

Well, either way, if it gets interpreted then thats another way of saying that it has a semantics, and I think we ought to make at least a minimal amount of that semantics official.

> Using examples where one man's proposition is another man's fact:
> 
> = Quoting (truth deferral) =
> Bob says the moon is made of green cheese:
>    <theMoon> <madeOf> <greenCheese> .
> Alice adds that to her dataset of crackpot theories.
>    <Bob> a <Crackpot> ; <says> _:x .
>  _:x { 
>    <theMoon> <madeOf> <greenCheese> .
>  }
> 
> If you believe Bob's dataset, the moon is made of green cheese. If you believe Alice's, Bob simply said that.

All assuming a *hell* of a lot more about what <says> means, and about how bnodes in RDF connect to bnodes used as labels, than anyone is going to dream of specifying here before LC.

> 
> 
> I spent a moment fiddling around with going the other way for truth promotion. I haven't figured out how it affects my thesis above, but maybe this example will help others flush this out:
> 
> = Believing (truth promotion) =
> Ted publishes theoryX which follows from theories Y and Z:
>    <theoryX> consequentOf <theoryY>, <theoryZ> .
>  <theoryX> {
>    <theMoon> <madeOf> <starDirt> .
>  }
>  <theoryY> {
>    <StellerBody> rdfs:subClassOf [ owl:onProperty <madeOf> ; owl:hasValue <starDirt> ] .
>  }
>  <theoryZ> {
>    <theMoon> a <StellerBody> .
>  }
> 
> Alice presumes Y and Z and could capture Ted's theory as a truth:
>    <theoryX> consequentOf <theoryY>, <theoryZ> .
>    <theoryX> a <Truth> . <theoryY> a <Truth> . <theoryZ> a <Truth> .
>  + Ted's named graphs.

Whats the difference between saying <x> and saying <x> a <Truth> ? The second only asserts that x is true if saying something asserts it, and if that is generally accepted then just saying x gets the job done. 

Pat


> 
> 
>> Got a better way to word it?
>> 
>> Pat
>> 
>> On Jun 21, 2013, at 1:38 AM, Peter F. Patel-Schneider wrote:
>> 
>>> Given that Semantics doesn't talk about publishing, I don't think that this is a good idea at all.
>>> 
>>> peter
>>> 
>>> On Jun 19, 2013, at 11:43 PM, Pat Hayes <phayes@ihmc.us> wrote:
>>> 
>>>> Have we agreed on Sandro's idea for the meaning of a datastore to be that of its default graph? I would like to add this paragraph to Semantics, section 10:
>>>> 
>>>> <p>If a dataset is published as an assertion then it MUST be interpreted to be an assertion of its default graph. Semantic extensions MAY impose extra conditions which require other named graphs to be interpreted in particular ways. </p>
>>>> 
>>>> Pat
>>>> 
>>>> ------------------------------------------------------------
>>>> IHMC                                     (850)434 8903 or (650)494 3973   
>>>> 40 South Alcaniz St.           (850)202 4416   office
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>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>> 
>>> 
>>> 
>> 
>> ------------------------------------------------------------
>> IHMC                                     (850)434 8903 or (650)494 3973   
>> 40 South Alcaniz St.           (850)202 4416   office
>> Pensacola                            (850)202 4440   fax
>> FL 32502                              (850)291 0667   mobile
>> phayesAT-SIGNihmc.us       http://www.ihmc.us/users/phayes
>> 
>> 
>> 
>> 
>> 
>> 
> 
> -- 
> -ericP
> 
> 

------------------------------------------------------------
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Received on Saturday, 22 June 2013 22:23:25 UTC