Re: ISSUE-3: REPORTED: Lack of anonymous individuals

On Thu, 8 Nov 2007, gstoil@image.ece.ntua.gr wrote:
>
> Carsten Lutz <clu@tcs.inf.tu-dresden.de> said:
>
>>
>> On Thu, 8 Nov 2007, gstoil@image.ece.ntua.gr wrote:
>>>
>>>> But *do* allow it in existential and universal restrictions.
>>>
>>> Sorry but I don't see where the definition differentiates between
>>> SROIQ-QCR-concepts and SROIQ-valua/existential-concepts.
>>>
>>> For example, I don't see how the current algorithm could classify
>>> {a:\not \exists uprop.Self} as inconsistent.
>>
>> I would have to look into the algorithm. Maybe Uli can comment on this.
>> On the other hand, I don't care too much about this point. We are not
>> formalizing this algorithm, we are designing OWL 1.1. And whether or not
>> it is in that particular algorithm, I keep up my claim that it is
>> technically not difficult. We should rather discuss whether we think
>> it is useful enough to be included. I do.
>
> Well many things are usefull, but besides usefullness we also have to look
> into "doability" in order not discover surprising things afterwards.
> Although your feeling is that these are technically not difficult let me
> have my doubts since if these could give you true anonymous individuals
> which in turn are not easy, then maybe things are not so obvious.

Please look into the SROIQ paper, section "reduction of inference
problems".  There it is explained that the universal role can be
eliminated by a simple reduction.

greetings,
 		Carsten

--
*      Carsten Lutz, Institut f"ur Theoretische Informatik, TU Dresden       *
*     Office phone:++49 351 46339171   mailto:lutz@tcs.inf.tu-dresden.de     *

Received on Thursday, 8 November 2007 15:26:43 UTC