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Re: ISSUE-111 Proposal to Resolve

From: Jim Hendler <hendler@cs.rpi.edu>
Date: Tue, 19 Aug 2008 11:21:43 -0400
Cc: Ian Horrocks <ian.horrocks@comlab.ox.ac.uk>, public-owl-wg Group WG <public-owl-wg@w3.org>
Message-Id: <A4A726A4-7180-459A-A41E-23CB15307219@cs.rpi.edu>
To: Bijan Parsia <bparsia@cs.man.ac.uk>

but isn't that a circular argument -- you say people will use sameAs  
sameAs sameAs to signal intent, but it will be bad for them to have to  
have something to signal intent.
Basically, my problem is that I firmly believe that in language design  
the overloading of terms is a bad idea.  SameAs has a very specific  
meaning and it is highly used - someone seeing sameAs sameAs sameAs in  
an ontology seems to me to be much more likely to be confused than  
someone seeing "owl2:OWLFullOnly" or whatever semantics free tag we  
use -- we could even put it within the ontology header --- seems to me  
you still haven't really shown me a downside -- you say the downside  
is that people would need to signal intent, but then propose a  
solution where they still have to signal intent, just in a less  
transparent way
  btw, I'm also fine with a solution where there is no signaling at  
all for OWL Full, which might be the compromise -- the thing I don't  
like is the overuse of existing syntax - so another alternative is to  
simply leave things as they are in OWL 1.0 (i.e. that ontologies are  
what they are) - would that be more acceptable?
  -JH
p.s. And again, let me stress that I would suggest we only create one  
term, and it is only intended for OWL Full only -- I do indeed agree  
that generally signaling intent is a bad idea - but if the WG feels it  
is needed for some reason in this case only, then we should do  
something explicit.


On Aug 19, 2008, at 10:05 AM, Bijan Parsia 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'm happy with sameAs sameAs sameAs myself. On the other hand, it's  
> not a huge win as an OWL
>
>> -- 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
>
> Oh. A big problem is the problem with introducing any new syntax  
> with "special meaning" but no defined meaning, people read too much  
> in it. This was, in fact, my original thought but we immediately got  
> off into the weeds. The nice thing about using a Full theorem is  
> that it reuses the *existing* profile detection mechanisms so  
> doesn't introduce a new conceptual catagory.
>
>> -- and would make things easier for both implementors
>
> I don't think so since they already need a detector. It's clearly  
> additional (if minor) work.
>
>> and users
>
> I'm not sure. Either way requires some learning but using existing  
> syntax doesn't require an additional conceptual category.
>
>> Guess what I'm trying to ask is what would be the downside?  I can  
>> only see positive advantages as an implementor
>
> Downside is that you have to recognize the new syntax (which is  
> minor). But also, I think it would be a point of confusion that I'd  
> end up explaining over and over again :) One really nice thing about  
> the current solution is that it's much less likely to be (mis) used  
> as a signaling of intent. I.e., "I *THINK* I may end up in OWL Full,  
> so I'll say I'm OWL Full".  Since this *is* a corner case (e.g., you  
> use it when you think owl:Thing should necessarily infinite)  
> building a new mechanism when that mechanism isn't needed seems  
> risky. Things added to the language should signal important stuff.  
> Having to learn that there is this syntax but yet it only matters  
> for a corner case is wasted cognitive effort.
>
> 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
Received on Tuesday, 19 August 2008 15:22:37 GMT

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