- From: Xavier Noria <fxn@hashref.com>
- Date: Wed, 26 Oct 2005 12:30:06 +0200
- To: Semantic Web <semantic-web@w3.org>
On Oct 26, 2005, at 11:47, Jon Hanna wrote:
>
> Xavier Noria wrote:
>
>>> It *is* possible to say that, for example, all people have mothers
>>>
>> In which formalism can you express that?
>>
>
> OWL allows you to define a cardinality on how a property applies to
> a particular class. <http://www.w3.org/TR/owl-ref/#cardinality-def>
I don't agree there (but maybe my interpretation is wrong, please
correct me in that case).
My reading of that description is:
IF a person has a mother THEN it has exactly one
but you can have a person WITHOUT a mother and be consistent (not
because of the open-world assumption, but because the semantic of
owl:Cardinality does not imply that *for all*).
-- fxn
Received on Wednesday, 26 October 2005 10:30:49 UTC