Re: ISSUE-83 (Vipul): Property Chain Axiom: P1 o P2 => P2 o P1 (really ISSUE-64)?

On Dec 3, 2007, at 3:35 AM, Bijan Parsia wrote:

> On Dec 2, 2007, at 10:14 PM, Alan Ruttenberg wrote:
>
>> Isn't this already permitted due to the resolution of issue 64?
>> http://www.w3.org/2007/OWL/tracker/issues/64
>
> No. That just changes the serialization of exisiting chain axioms.  
> It doesn't introduce new axioms though it does *allow* for new  
> classes of axioms e.g.,:
>
> """In OWL 1.1 Full one could use this everywhere, and not just in  
> the rdfs:subPropertyOf."""
>
> Note the "could".

OK, then the misunderstanding was over the "could". I read it as can,  
as in "In OWL 1.1 Full one can use this everywhere, and not just in  
the rdfs:subPropertyOf".

But then, in OWL Full (no qualifier), one is allowed to have *any*  
rdf. So isn't it in OWL Full, by definition,  as one can express it  
syntactically. What is the process by which semantics gets in to OWL  
Full? The issue would seem to be whether any OWL Full semantics are  
given to this construct. My understanding is that someone *could* do  
that, but that we would not delay our schedule to enable it.
Didn't Boris' message give a semantics?
> the semantics of <x owl11:propertyChain LIST[y1 ... yn]> would then  
> be "the extension of x is obtained by chaining together y1, ..., yn"
>

What is the status of this statement. If it is not intended to be  
part of the spec, then should we amend the resolution? If it is, how  
is this not what I've suggested - the answer to Vipul's question - in  
OWL Full, not OWL-DL.

Anyways, this isn't by way of advocating one way or another, but to  
try to clarify what has happened, what will happen, and how we record  
what our decisions are.

Regards,

Alan

Received on Monday, 3 December 2007 18:18:46 UTC