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Re: New version of URI Declarations [Usage scenarios]

From: Pat Hayes <phayes@ihmc.us>
Date: Fri, 14 Mar 2008 12:56:43 -0500
Message-Id: <p06230903c4006950a60f@[192.168.1.2]>
To: John Cowan <cowan@ccil.org>
Cc: "Booth, David (HP Software - Boston)" <dbooth@hp.com>, "www-tag@w3.org" <www-tag@w3.org>
At 12:23 PM -0400 3/14/08, John Cowan wrote:
>Pat Hayes scripsit:
>  > You are ignoring the central point. What if your 'defining'
>>  assertions are wrong, or contain a flaw of some kind? Does this
>>  change the reference (so they are not in fact wrong at all, just
>>  talking about something else) or is it a factual error?
>
>The former.  This encourages you to choose them carefully, and if other
>people choose them poorly, to disregard their names.

But this isn't how people in fact use names. They use them to refer, 
and if they say wrong things about the referents using the names, 
they correct those things rather than invent a new name. I very much 
doubt if people will change these deeply held habits to suit some 
proclamation from on high about declarations, nor indeed should they.

>
>>  How can we even discuss this matter, if we cannot even contemplate
>>  the possibility that an assertion in a declaration might be false?
>
>By saying that the resulting definition is not useful.
>
>>  OK, then it follows that YOU are using your own name incorrectly,
>>  right?
>
>Sorry, this is unintelligible to me.

I don't believe you. Its perfectly intelligible, even to you. It just 
violates this fantasy that you guys are wanting us all to buy into. 
I'll give you an example. Suppose that you were to declare jc:moon in 
the way you described, and then another natural earth satellite is 
discovered (perhaps extremely small and dark, which is why it was not 
noticed before, but spectral analysis shows that it is a genuine 
piece of moon-type rock, formed at the same approximate time and in 
the same event as the moon was formed.) Now, your declaration of 
jc:moon no longer identifies the big moon. But I bet that, just like 
everyone else, you will will think of the URI as still denoting the 
big moon, and would prefer to correct your definition rather than 
invent a new name for the very same thing. The cost of inventing a 
new name and retaining the old definition attached to the old URI is 
far more than just fixing the description. Possibly millions of other 
ontologies will need to be altered: and for what? The intended 
referent of the name hasn't changed, so what is all the fuss about?

>  > This does not seem to fit well with the notion that an owner
>>  of a URI has control over what it denotes.
>
>Control, yes; but if the URI is to be useful, it cannot be merely "The
>URI u means what I want it to mean, changeable at whim"

That is precisely what I want to avoid. Note however that it 
certainly can be "Im not sure exactly what this denotes, but it 
doesn't matter; because if you agree with what I say about it, we can 
communicate on that basis", which does not require any kind of 
declaration at all.

>, nor yet "The URI
>u means what I mean to refer to when I use the URI u."  See Kripke again,
>and note, to fend off an obvious misunderstanding, that the second formulation
>is *not* circular even though it is useless.

I agree its not circular, but I also don't think it is is useless. In 
fact, there is good reason to suppose that most communication between 
human beings has exactly this character. None of us know exactly what 
others are referring to, and it almost never matters.

Pat

>
>--
>John Cowan    cowan@ccil.org    http://ccil.org/~cowan
>If a traveler were informed that such a man [as Lord John Russell] was
>leader of the House of Commons, he may well begin to comprehend how the
>Egyptians worshiped an insect.  --Benjamin Disraeli


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Received on Friday, 14 March 2008 17:57:21 GMT

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