Re: [Fwd: Re: [DTB] Datatypes and Built-ins first run to clean up and extend the initial list]

Jos de Bruijn wrote:
> 
> 
> Dave Reynolds wrote:
>>
>> Jos de Bruijn wrote:
>>
>>> So, we really want to take into account all IRIs representing a 
>>> particular domain element.  Since this is a set, we would need to use 
>>> a built-in predicates.  For example:
>>>
>>> "Let I be an interpretation, let u be an element in the domain of I, and
>>> let {i1, ..., in} be the set of IRIs that denote u, i.e. for each ij 
>>> (1 <= j <= n) IC(ij)=u.  IR(iriToString)(u,"ij")=t for (1 <= j <= n); 
>>> IR(iriToString)(u,s)=f for every element s not in {"i1", ..., "in"}."
>>>
>>> The rule set
>>> iriToString("b"^^rif:iri,"b"^^xsd:string)
>>>
>>> is satisfied in every RIF interpretation.
>>
>> But in any semantic web context  one couldn't determine the truth or 
>> falsity of:
>>
>>  iriToString("foo"^^rif:iri,"bar"^^xsd:string)



> right.  In some interpretations the formula might be true, whereas in 
> other interpretations it would be false.  So, it would not be entailed 
> by the empty rule set.

but it would be entailed if the remaining theory entails

  "foo"^^rif:iri = "bar"^^iri

right?


> Best, Jos
> 
>>
>> Dave
> 


-- 
Dr. Axel Polleres
email: axel@polleres.net  url: http://www.polleres.net/

rdfs:Resource owl:differentFrom xsd:anyURI .

Received on Tuesday, 4 March 2008 15:39:19 UTC