Re: Question on special class description

Hi Lennart,

I can only see two ways, and they lead out of OWL-DL, but perhaps  
someone else here has a better idea?

(1) If you use Boolean operators on roles, you can define a new role  
hasChildButDoesNotLoveIt to be "hasChild and not loves". You can then  
define the desired class as GoodParent = hasChildButDoesNotLoveIt only  
Nothing.

(2) If you define a new property p to be a superproperty of the chain  
"hasChild o inv(loves)", then you can define a GoodParent to be  
equivalent to not p some Self. Unfortunately, only simple object  
property expressions are allowed in hasSelf restrictions and p is  
composite due to the first statement.

I suppose this doesn't really help ... :-S

Cheers

Thomas

On 23 Feb 2010, at 15:35, Lennart Bierkandt wrote:

> Hello,
>
> I am developing an ontology for a linguistic typological database,  
> where I need to describe a class of the form:
> { x | ∀y( r1(x,y) -> r2(x,y) ) }
> As explaining the real use of this would be to complicated, imagine  
> a class denoting e.g. "people who love (r2: loves) all their  
> children (r1: hasChild) (or haven't any)".
>
> In prose it doesn't seem to be too complex, but I didn't find a way  
> to do it..
> CAN this be expressed in OWL-DL? and if, how? (and if not, in OWL- 
> FULL?)
>
> Kind regards,
> Lennart Bierkandt
>
>
>

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