Re: User-defined Datatypes: owl:DataRange vs rdfs:Datatype

No, I've got it wrong. My mistake is that the fact that the names are  
disjoint sets doesn't mean what I suggest. Specifically "Only classes  
have instances" appears wrong since the set EC which I understand to  
be "instances" is the union of individuals and data values.

I think the correct answer will be found here: http://www.w3.org/TR/ 
owl-semantics/rdfs.html#5.4

I'll try again later.

Thanks,
Alan

On Dec 7, 2006, at 8:20 AM, Dave Reynolds wrote:

>> If I understand this correctly,  it says that VC (the class names  
>> of a vocabulary) and VD(the datatype names of a vocabulary) are  
>> disjoint. That is, a datatype is not a class. Only classes have  
>> instances. So even for the built-in xsd:int, the statement from  
>> RDFS "xsd:int, is a subclass of rdfs:Literal" can't hold. And so  
>> user defined datatypes are no different than the builtins.
>
> Surely VC here is the set of owl:Classes which is a subset of the  
> set of rdfs:Classes. The statement:
>
>    xsd:int rdfs:subClassOf  rdfs:Literal .
>
> can and does hold in RDFS, it is just that both of these are  
> rdfs:Classes but not owl:Classes. Such a statement is of course not  
> valid OWL/DL (and thus presumably not OWL 1.1) but it is perfectly  
> good OWL (with species type OWL/full).
>
> Dave