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Re: Denotation of URIs

From: Seth Russell <seth@robustai.net>
Date: Mon, 14 Apr 2003 11:43:31 -0700
Message-ID: <3E9B0153.7050705@robustai.net>
To: Patrick.Stickler@nokia.com
CC: pfps@research.bell-labs.com, www-rdf-interest@w3.org

Patrick.Stickler@nokia.com wrote:

>  
>
>>-----Original Message-----
>>From: ext Seth Russell [mailto:seth@robustai.net]
>>Sent: 11 April, 2003 19:17
>>To: Stickler Patrick (NMP/Tampere)
>>Cc: pfps@research.bell-labs.com; www-rdf-interest@w3.org
>>Subject: Re: Denotation of URIs
>>
>>
>>Patrick.Stickler@nokia.com wrote:
>>
>>    
>>
>>>>Ambiguity of denotion is bad relative to what?  
>>>>   
>>>>
>>>>        
>>>>
>>>Reliably communication. I.e. consider a recent example
>>>
>>>If the URI being used to denote who the first lady
>>>is, is being used ambiguously, then there is no way to actually
>>>test for any disagreement. I.e., I may assert that _:a denotes
>>>Jane and she lives at address X, but that _:b denotes Betty and
>>>she lives at address Y. If you use _:a to denote Betty and assert
>>>that Betty lives at address X, I will see no contradiction, because
>>>according to my understanding of _:a you are saying that Jane lives
>>>at address X!
>>>
>>>So, disagreement about what a URI denotes prevents reliably
>>>communication and even the ability to know if different folks
>>>disagree about various things.
>>>
>>>      
>>>
>>Yes, I totally agree.  
>>
>>    
>>
>>> 
>>>
>>>      
>>>
>>>>But such 
>>>>ambiguity is not necessarily bad relative to 3 state logic 
>>>>        
>>>>
>>where the 
>>    
>>
>>>>third state is interperted as "Surprise" or "Error" and that state  
>>>>tells us that the law of the excluded middle cannot be 
>>>>        
>>>>
>>applied in the 
>>    
>>
>>>>current context.  Is 3 state logic not a possible way out of 
>>>>this morass ?
>>>>   
>>>>
>>>>        
>>>>
>>>I don't think that the unambigous denotation of URIs has 
>>>      
>>>
>>anything (directly)
>>    
>>
>>>to do with binary vs. 3 state logic.
>>>
>>>Regardless which logic you use, your atomic primitives must 
>>>      
>>>
>>be consistent.
>>    
>>
>>Uuh ... that is not a true statement.  If someone (or even in 
>>the future 
>>some software agent) wisely uses the kind of human reasoning 
>>that people 
>>are accustomed to use with natural language, they should know 
>>that their 
>>"atomic primitives" need not necessarirly be consistent.  
>>    
>>
>
>Fair enough. And when a SW agent passes the Turing test, I'll
>back off on my adamant position that ambiguity of denotation is
>unnacceptable on the SW.
>
>Until then...  it's bad, bad, bad ;-)
>

ok ok ok.

>
>  
>
>>>The inferences you make, by whatever logic, based on 
>>>      
>>>
>>assertions *using*
>>    
>>
>>>those atomic primitives is separate issue entirely. 
>>>
>>>URIs are the atomic primitives of the SW, and whatever model 
>>>      
>>>
>>of logic you
>>    
>>
>>>might apply to interpeting assertions expressed in RDF and 
>>>      
>>>
>>infering new
>>    
>>
>>>knowledge, those URIs should have globally consistent, unambigous
>>>denotation.
>>>
>>>      
>>>
>>I agree,  "unambigous denotation of URIs" (U) and "what kind of logic 
>>you use" (L) are two separate things.  I am just saying that to the 
>>extent that you trust that you  have U,  then you can use a strong L 
>>(like for instance one where A==A), to the extent that you do 
>>not trust 
>>U or even find that it leads to contradictions, you should 
>>use something 
>>else.   The fact is, and hopefully you will agree with me here, 
>>everybody in the world  is just not going to use a URI to denote the 
>>same thing across the board and in all cases;  and to assume 
>>that they 
>>will is going to sort out to be just down right stupid.  The 
>>idea that 
>>they *should* always denote the same thing is like the idea that 
>>everybody *should* always obey the law.  
>>    
>>
>
>I fully agree, and have used examples which reflect this view. I don't
>think that any of my posts have reflected anything that contradicts
>this view.
>
>But it seems that some folks would like to say that, since folks won't
>obey the law, we shouldn't have any laws...
>

Kewl then we totally agree :)  ... except perhaps that i dont think it 
should even be a law or even an assumption or even an axiom but rather 
just the consensus of the w3c working groups.

>
>  
>
>>I believe that the mentograph below does express that quite usefully.
>>
>>http://robustai.net/mentography/3laws.jpg
>>    
>>
>
>I'll have a look.
>

I guess embedded somewhere between the lines of my posting is the 
question whether that rule can be used somewhere in a reasoning engine 
to switch the kind of logic that is used and if that would perhaps help 
us to some day pass the turning test above ...  huh ... anybody ?


Seth Russell
Received on Monday, 14 April 2003 14:43:42 GMT

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