- From: Jim Hendler <hendler@cs.rpi.edu>
- Date: Tue, 19 Aug 2008 12:25:27 -0400
- To: Ian Horrocks <ian.horrocks@comlab.ox.ac.uk>
- Cc: Bijan Parsia <bparsia@cs.man.ac.uk>, public-owl-wg Group WG <public-owl-wg@w3.org>
Ian, I apologize, I didn't mean to imply anything was wrong I think by now you have seen my email with two possible ways forward - a specific "tag" or,my preference, a decision not to include any such wording. Bijan, I don't agree it is just editorial since this whole discussion came up in response to an issue and we need to resolve to close that issue as a wg. Sent from my iPhone On Aug 19, 2008, at 11:48 AM, Ian Horrocks <ian.horrocks@comlab.ox.ac.uk> wrote: > Jim, > > I'm not trying to force you to agree to anything, nor do I > "disagree", nor am I "involved" in the issue in the sense that I > have an axe to grind -- as far as I am concerned closing with no > action would be just fine, but at the F2F the sameAs^3 idea was > proposed as a compromise. > > What I have been trying to do is to push the issue towards > resolution (something that I believe is completely consistent with > my chair role) by getting you to explain more clearly what your > objection is and how you would like the issue to be resolved. The > first has started to become a little more clear, but the second is > still *very* unclear. > > Ian > > > > > wanted to have at least > > On 19 Aug 2008, at 14:44, Jim Hendler wrote: > >> Ian - sameAs^3, if made "THE" thing to use would solve the problem, >> it would just be very counterintuitive to real users -- I see no >> advantage over adding some small semantics free declarative to OWL >> Full documents (and remember it is only OWL Full) - and, I'm sorry, >> maybe you see me as being unreasonable, but I simply don't see any >> way I can sign on to the current proposal -- Look, let me put it >> this way - you will not convince my organization that the sameAs^3 >> solution (esp. as curently set up where any error signals an >> intent) is a good one. We can go back and forth as much as you >> want, but my organization won't agree to the current closing text >> I know you don't like discussion of W3C process, but basically, >> going back and forth on this won't get us anywhere, you and I >> simply disagree - since you're involved in the discussion, Alan >> should either schedule a vote or propose an alternative and then we >> can move on - not every WG member needs to agree with everything, >> and I've stated my objection for the WG to consider so I've been >> treated fairly >> -JH >> >> >> On Aug 18, 2008, at 4:13 PM, Ian Horrocks wrote: >> >>> On 18 Aug 2008, at 17:04, Jim Hendler wrote: >>> >>>> Bijan, >>>> It is absolutely true as you say that if it is in OWL Full then >>>> it is in OWL Full (you said it better), but the key here is we're >>>> talking about when the user explicitly wants to signal that it >>>> should be OWL Full -- seems to me having a very specific thing, >>>> easy to find, in this particlar (and probably rare) case would >>>> make everyone's lives easier -- I don't understand the >>>> reluctance, I've looked at the discussion in the f2f, and it >>>> seems to mainly concern general issues with signaling intent, >>>> which I mostly agree with, the problem is this one specific case >>>> - and why can't we just have some little piece of syntax, which >>>> is only in OWL Full, which basically says "Don't expect complete/ >>>> sound reasoning if you use me with an OWL DL tool" - seems to me >>>> we could do something more mnemonic that sameas Sameas sameAs -- >>>> and would make things easier for both implementors and users >>> >>> sameAs^3 seems to do exactly what you want without the need to >>> introduce any new OWL RDF vocabulary, and it is at least easy to >>> remember (even if not mnemonic). I'm open to suggestions, though, >>> as to some other piece of OWL Full that could be used for the same >>> purpose -- but remember that one of the criteria is that it should >>> be vacuous (i.e., be entailed by every OWL Full ontology). >>> >>> Ian >>> >>> >>> >>>> Guess what I'm trying to ask is what would be the downside? I >>>> can only see positive advantages as an implementor >>>> -JH >>>> >>>> >>>> On Aug 18, 2008, at 10:48 AM, Bijan Parsia wrote: >>>> >>>>> >>>>> On 12 Aug 2008, at 13:10, Jim Hendler wrote: >>>>> >>>>>> >>>>>> OK, so supposing I'm an OWL DL user and I want to use a DL >>>>>> reasoner. I accidently, however, assert something that puts >>>>>> the ontology in Full (and when we did the analysis of 1500 >>>>>> ontologies 3 years ago, there were at least 100 for which this >>>>>> case was true -- usually because someone referred to something >>>>>> from a remote name space without adding the appropriate type or >>>>>> imported something that put them into Full without their >>>>>> realizing it) -- so according to this, tools like Pellet, >>>>>> instead of "fixing" these mistakes (heuristically) would now >>>>>> need to assume the person knew what they were doing and that >>>>>> they want to be in Full >>>>> >>>>> No. If an ontology is syntactically in OWL Full it is in OWL >>>>> Full. This has *always* been true. >>>>> >>>>> How to *handle* OWL Full ontologies remains, as it was then, up >>>>> to the tool. Pellet performs an analysis and repair phase with >>>>> reports back on the repairs performed and a strict mode. Nothing >>>>> would change with that. >>>>> >>>>>> -- so it would be rare that they want to do this on purpose, >>>>>> but not rare that it would happen by accident. >>>>>> My point is not that I think there shoudln't be some way to do >>>>>> this, but rather that it should be explicit -- otherwise we get >>>>>> in a situation where tools will assume it's a mistake, and then >>>>>> the user will have to do something extra to make it clear they >>>>>> meant it >>>>>> So my argument is not that we should have some way to always >>>>>> signal intended use, but that for this corner case, we should >>>>>> have something unambiguous that is not likely to be used by >>>>>> mistake (which is why, sameAs sameAs sameAs seems appealing) >>>>> >>>>> I think if we give advice and follow that advice up with tools >>>>> support (e.g., in the report say, "This ontology is OWL Full >>>>> only in virtue of the notorious sameAs^3 triple which generally >>>>> means that this is intended to be owl full. This reasoner does >>>>> not support OWL Full semantics, would you like the (sound but >>>>> incomplete wrt subusmption) OWL DL results anyway?" >>>>> >>>>> Cheers, >>>>> Bijan. >>>>> >>>>> >>>> >>>> "If we knew what we were doing, it wouldn't be called research, >>>> would it?." - Albert Einstein >>>> >>>> Prof James Hendler http://www.cs.rpi.edu/~hendler >>>> Tetherless World Constellation Chair >>>> Computer Science Dept >>>> Rensselaer Polytechnic Institute, Troy NY 12180 >>>> >>>> >>>> >>>> >>> >> >> "If we knew what we were doing, it wouldn't be called research, >> would it?." - Albert Einstein >> >> Prof James Hendler http://www.cs.rpi.edu/~hendler >> Tetherless World Constellation Chair >> Computer Science Dept >> Rensselaer Polytechnic Institute, Troy NY 12180 >> >> >> >> >
Received on Tuesday, 19 August 2008 16:26:44 UTC