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Re: datatypes and MT (things versus their names: PRIMER)

From: Pat Hayes <phayes@ai.uwf.edu>
Date: Tue, 6 Nov 2001 20:07:13 -0600
Message-Id: <p05101048b80e43a23e8a@[65.212.118.166]>
To: Dan Connolly <connolly@w3.org>
Cc: w3c-rdfcore-wg@w3.org
>Pat Hayes wrote:
>>
>>  >Brian McBride wrote:
>[...]
>>  >People often write
>>  >   :s eg:shoeSize "10".
>>  >   :s nav:date "2001-11-02".
>>  >   :s nav:time "16:14".
>>  >   :s nav:flightNum "1154".
>>  >   :s nav:customerNumber "678".
>  > >   :s apt:latitude "50-54N".
>>  >   :s apt:longitude "004-32E".
>>  >   :s apt:elevation "58M".
>>  >or in general
>>  >   :s :p "ooo".
>>  >and I believe that is a shorthand for
>>  >   :s :p [ rdfs:str "ooo" ].
>>  >(I used to prefer rdfs:label instead of rdfs:str
>>  >but now I think that rdfs:str is a better name for
>>  >the property mapping a data value (that bNode)
>>  >to it's string representation)
>>
>>  I have serious problems with this. For a start, why on earth would
>>  anyone say that latitude and longitude and elevation were *strings*?
>>  They clearly aren't strings, so this is just plain wrong.
>
>(a) I agree people write stuff this way, and (b) I agree
>it's just plain wrong, so (c) I think it's critical that
>this issue (things versus their names, numbers vs. numerals...)
>is treated by the primer.

Well, hang on. I don't disagree with your general point, but there is 
an alternative way to interpret what is going on. Maybe the people 
who write this stuff aren't philosophically boneheaded, they are just 
not assuming that those things in double quotes are strings. That is, 
when they write

   :s apt:latitude "50-54N".

they do not see that as saying that the latitude is a string. What 
they are assuming, rather, is that this literal-thingie, wrapped in 
double quote marks, is supposed to indicate a longitude. (Exactly 
how, is a more complicated story....) That is not an unreasonable way 
to use double quotes if you are trained in an XML world rather than a 
strict use/mention logical world. That is exactly what the MT 
extension tries to do, ie to interpret literals not (necessarily) as 
strings, but rather as labels that denote just as other node labels 
do, but in a special way determined by a datatype.

The moral of which observation is that we maybe ought to just admit 
that our double quote marks round literals are *not* quotation marks 
in the semantic sense, rather than try to whip the entire world into 
semiotic order.

>Case in point: folks write
>	<dc:creator>Dan Connolly</dc:creator>
>as if a character sequence "D" "a" "n" ... wrote a book.
>It's critical that we teach folks to write
>	<dc:creator>
>	  <Person>
>	    <fullName>Dan Connolly</fullName>
>           </Person>
>         </dc:creator>
>
>or, more briefly:
>	<dc:creator contact:fullName="Dan Connolly"/>

I don't follow. Why does

	<dc:creator>Dan Connolly</dc:creator>

imply that a character sequence wrote a book? Surely the markup here 
should be interpreted as saying that the enclosed text *refers to* 
the author, not that it *is* the author. There aren't even any 
confusing quote marks around. It seems crazy to me that I should have 
to wrap every piece of text I use with two extra layers of markup 
just so that I can be mentioning it rather than using it. I didn't 
want to mention it in the first place.

Pat



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Received on Tuesday, 6 November 2001 21:07:24 EST

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