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Re: Relation between OWL and OWL-S

From: Bijan Parsia <bparsia@isr.umd.edu>
Date: Mon, 29 Nov 2004 10:47:27 +0900
Message-Id: <9FA59F9E-41A8-11D9-B962-000D93C1F7A6@isr.umd.edu>
Cc: public-sws-ig@w3.org
To: Drew McDermott <drew.mcdermott@yale.edu>

On Nov 29, 2004, at 8:28 AM, Drew McDermott wrote:

>>> [me]
>>> I think you are still confused about where natural language ends and
>>> internal representation begins.
>>
>> [Bijan Parsia]
>> "Formal" representations? There's not a real sense in which an OWL
>> document is *internal* to anything, in most respects.
>
> One perenially needs a term for "declarative notation used by a
> computer that may use mnemonics derived from natural language but is
> not actually natural."

Indeed.

>   I use the term "internal representation."

The problem with that is that it conflicts with the sense in which Sexp 
are an external represenation (e.g., of a procedure) while there is 
something else (cons cells, machine code) that is the internal 
representation. In XML, we have the serialized XML vs. the PSVI or DOM.

> I
> guess one could say "formal" instead, but it's a stretch in the case
> of some representations to believe they're formal in any substantive
> sense.

True, but in the case of OWL it seems ok to say formal. I'm not sure if 
"declarative" is sufficent, but it's certainly suggestive.

>>>   Internally all we have to do is use
>>> two different symbols, and the two entities are "differentiated."
>
>> In OWL, this is necessary but not sufficient.
>
> By "differentiated" I meant "not provably equal," not "provably not
> equal."

Name distinctiveness is not sufficient to show that they are provably 
not equal. A = B.
[snip]
>> [snip]
>>
>> or just assert that the two individuals are distinct.
>
> If someone wants to split hairs (and there are lots of people hanging
> around with nothing better to do, I've noticed --- present company
> excepted),

The problem with having something better to do is that that something 
better might be less fun or substantially harder than hair splitting.

(Check out Rushie's "Shame" for a rather graphic hair splitter.)

>  they might observe that asserting not(a=b) _is_ a property
> that differentiates a and b, to wit, the property of being b, which b
> has and a apparently does not.

It occured to me to split that hair or rather to unsplit that hair, but 
given how (in)equality is typically treated specially it seemed worth 
distinguishing the case where there is nothing *but* the inequality 
(i.e., a raw assertion of bare difference) and the case where two 
individuals are not the same in virtue of some other incompatible 
property. Of course, with the UNA, difference in term is a sufficient 
property for inequality.

Cheers,
Bijan.
Received on Monday, 29 November 2004 01:47:27 GMT

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