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Re: simplified datatyping proposal

From: Pat Hayes <phayes@ai.uwf.edu>
Date: Thu, 21 Feb 2002 17:34:17 -0600
Message-Id: <p05101413b89b322af165@[65.212.118.219]>
To: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
Cc: w3c-rdfcore-wg@w3.org
>Pat,
>
>I'm rolling up responses to several or your messages into one here, 
>in the hope and belief that various misunderstandings are becoming 
>unmisunderstood...

OK, thanks. Also apologies for low-blood-sugar-induced howling in 
previous messages.

>At 09:23 PM 2/20/02 -0600, Pat Hayes wrote:
>>AAARGH!!!  I wish you would say what it is you DO want. People keep 
>>contradicting themselves, no wonder we cant get to a resolution of 
>>this damnable issue.
>>
>>I thought that the whole point of the B idiom was that it DID allow 
>>datatyping to alter the denotation of the literal. If CC/PP doesn't 
>>need that, we don't need to allow the inline idiom to be sensitive 
>>to datatypes.
>>
>>Please will you say EXACTLY what you want to be able to do. Then I 
>>promise I will hit your target. But for Gods sake keep the target 
>>still for a while.
>
>Short-form response:
>
>Under Sergey's S proposal, the B idiom works with every literal 
>denoting itself.
>
>...
>
>Here is a slightly longer version:
>
>I have quite consistently not deeply cared what the literal 
>*denotes* in the B idiom ...
>(though I acknowledge that what I have said may not always convey that.)
>
>Indeed, my goal in presenting the idioms was to try and separate how 
>people use RDF literals from the model theoretic denotations.
>
>What I want to be able to do is define some schema that lets me say:
>
>    person:Jenny ex:age "10" .
>
>but that does not let me say

OK, but hold on there. There is no way to PREVENT anyone saying 
anything in RDF, right? What you mean, I hope, is that if someone 
does say the following, then a datatype checker will barf or maybe 
bark, right? I'll assume so unless you disabuse me.

>:
>
>    person:Jenny ex:age "Humpty Dumpty" .
>
>in the presence of some well-understood datatyping scheme for 
>representing the values that can be used as a measure of age. 
>Note, I say "in the presence of" -- I don't require that the "10" 
>denotes that measure, just that the literal values that can be used 
>here are somehow constrained;  i.e. under some schema, say:
>
>    ex:age rdfs:drange datatype:DecimalNumber .
>
>the statement:
>
>    person:Jenny ex:age "Humpty Dumpty" .
>
>would always be false

OK. But you don't care how it gets to be false, as it were.

>(given some reasonable understanding of "datatype:DecimalNumber"), but:
>
>    person:Jenny ex:age "10" .
>
>may or may not be true.
>
>I understand that the model theory must take some view about what 
>the literals denote, but for the purposes of this particular issue, 
>I don't care what that view is.  For example, under Sergey's S 
>proposal, the B idiom worked with every literal denoting itself. 
>Under other schemes, it worked with the literal denoting some 
>(datatype-defined) value.  My point is to refute your statement 
>above that "the whole point of the B idiom was that it DID allow 
>datatyping to alter the denotation".

OK, point taken. I had been misunderstanding this point all along, it 
seems: I thought the point of all those idioms was to get the 
denotations right. What worries me now is that other people may have 
been under the same impression.

>
>...
>
>And from another message:
>>>At 12:27 PM 2/20/02 -0600, Pat Hayes wrote:
>>>>Well, I half-agree, but we can't have all three things at once:
>>>>
>>>>1. You and Graham want range-sensitive inline literals.
>>>>2. Dan C. wants an inline literal used with no datatyping to 
>>>>unambiguously denote a character string.
>>>>3. We all want the logic to be monotonic.
>>>>
>>>>Something has to give.
>>>
>>>Didn't the S proposal achieve all that?
>>
>>No proposal can possibly achieve all that. Regardless of semantic 
>>ingenuity, those three are a logical contradiction by themselves. 
>>The *spec* is a contradiction, so theres no point trying to meet it.
>
>Hmmm... either I'm completely missing something, or we're stumbling 
>over what "range-sensitive inline literals" means.
>
>(I don't insist on range-sensitive denotation.)

Yes, we were stumbling. I took it to mean that.

OK, let me get back to y'all on that.

Pat

PS it occurs to me that if you are happy with the denotations being 
anything, then maybe this proposal could make everyone happy. The one 
person Im most worried about is Dan C....

Pat
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Received on Thursday, 21 February 2002 18:34:20 EST

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