Re: Intersection of properties?

Bijan Parsia wrote:
> 
> On Aug 3, 2008, at 7:58 PM, Jeff Thompson wrote:
> [snip]
>> I sounds like many implementors
> 
> No, it doesn't sound like that. Those were all theory papers.
> 
>> see that even OWL 2 is not expressive
>> enough to solve their data processing needs, and so everyone has
>> their own extensions in Pellet, etc.
> 
> ? No. The implementation of ALBO is not, by any means, production 
> quality (or would purport to be even vaguely scalable to realistic kbs). 
> There's only one, sorta implementation of PDL (Peter's DLP, which is 
> sorta defunct).
> 
> So, I don't know where you're getting this from :)
> 
>> And yet, the argument against
>> adding more expressiveness to OWL 2 (still decidable) is the fear
>> that not enough people will implement it and so that "OWL 2 compliant"
>> won't mean much.
> 
> What? The argument against boolean role boxes, in general, is that it's 
> relatively hard to do and there's been relatively little demand for it. 
> ALBO is *very* expressive but, you know, doesn't have cardinality 
> restrictions.
> 
> I personally don't feel a burning desire for role conjunction. Perhaps 
> you could list use cases?

I already implemented SWRL in Browlser.
http://browlser.sourceforge.net/
And so I'm trying to understand which of the implicit rules
in the OWL 2 axioms can be used instead of SWRL rules.
The "uncle" rule with role chains is a good example of where OWL 2 on
its own is good enough without having to spell out the rule in SWRL.
There are many SWRL rules I use which are of the form of role conjunction.
I also use the equivalent of role chains that end in a datatype but the
OWL working group has already rejected these.
http://www.w3.org/2007/OWL/tracker/issues/8
So I'm trying to understand what's "in" and what's "out" and why.

>> I know it's a difficult political task to balance.
>> Is the general assumption that there will need to be several more
>> revision cycles to OWL before a large number of people will use it
>> as specified without needing to add their own incompatible extensions?
> 
> I think you're confused. OWL already is used by a large number of people 
> without needing to add their own incompatible extensions. If you have a 
> strong need for very expressive role boxes, I suggest you submit a paper 
> to OWLED detailing your needs.

Thanks for the quick feedback.  There's a lot of work going on which is
exciting.

Cheers,
- Jeff

Received on Sunday, 3 August 2008 19:57:52 UTC