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Re: Why do you want to do that?

From: Frank Manola <fmanola@acm.org>
Date: Tue, 12 Aug 2008 14:36:02 -0400
To: "Richard H. McCullough" <rhm@pioneerca.com>
Message-Id: <39982F5C-7325-4067-89E9-2E93E4E80939@acm.org>
Cc: "Pat Hayes" <phayes@ihmc.us>, "Adam Pease" <adampease@earthlink.net>, "Semantic Web at W3C" <semantic-web@w3.org>, "KR-language" <KR-language@YahooGroups.com>


What's the ambiguity that's introduced?  It seems to me that when I  
treat something as both an individual and a class, in a logical  
language that allows it, it's perfectly unambiguous that you're doing  
that.  If I have a green car, something that's both a car and a green  
thing, there's no "ambiguity" as to whether it's a car or a green  
thing;  it's just both.  In these examples from the OWL Guide  
(assuming you choose to use OWL Full as indicated), there isn't any  
ambiguity either;  something is simply both an individual and a class.


On Aug 12, 2008, at 1:46 PM, Richard H. McCullough wrote:

> Hi Frank
> OK, I have been convinced there's a reason why you would want to do  
> that.
> The downside is that you introduce another ambiguity, which must be  
> resolved
> by context.
> Humans are pretty good at doing that.
> One aim of mKR is to make them even better at doing that.
> Dick McCullough
> Ayn Rand do speak od mKR done;
> mKE do enhance od Real Intelligence done;
> knowledge := man do identify od existent done;
> knowledge haspart proposition list;
> http://mKRmKE.org/
> ----- Original Message ----- From: "Frank Manola" <fmanola@acm.org>
> To: "Richard H. McCullough" <rhm@pioneerca.com>
> Cc: "Pat Hayes" <phayes@ihmc.us>; "Adam Pease" <adampease@earthlink.net 
> >; "Semantic Web at W3C" <semantic-web@w3.org>; "KR-language" <KR-language@YahooGroups.com 
> >
> Sent: Tuesday, August 12, 2008 7:48 AM
> Subject: Re: Why do you want to do that?
>> On Aug 12, 2008, at 1:56 AM, Richard H. McCullough wrote:
>>> I finally got a few minutes to read OWL Guide 3.1.3
>>> I read that section as supporting my position.  The word  
>>> "context"  is mentioned
>>> several times, with the implication that X ismem IndividualSet;  
>>> in  one context,
>>> and X ismem ClassSet; in a different context.
>> Dick--
>> I originally cited section 3.1.3 of the OWL Guide to answer a  
>> question you posed in your original message:  why someone might  
>> want an  individual to also be a class.  Specifically:
>> "The wine ontology as it currently exists would require the ability  
>> to treat classes as instances in order to support such an  
>> interpretation. Note that OWL Full permits such expressivity,  
>> allowing us to treat an instance of a wine variety simultaneously  
>> as a class whose instances  are bottles of wine."
>> and also
>> "Adding that the wine produced in the year 2000 is considered a   
>> vintage poses a challenge, because we don't have the ability to   
>> represent a subset of a given wine individual. This vintage is not  
>> a  new variety of wine, it is a special subset of the wine - that   
>> produced in the year 2000. An option would be to use OWL Full and   
>> treat the wine instances as classes with subclasses (subsets)  
>> denoting  vintages. "
>> Other examples (outside the OWL Guide) of why it can be useful to   
>> treat an individual as a class (or vice-versa) can also be cited.    
>> Perhaps you could clarify your position you think OWL Guide 3.1.3   
>> supports?  It doesn't seem to support a position (if that's your   
>> position) that no one would want to do that.
>> --Frank
>>>>> 2. X  type  Y;  X  subClassOf  Z;
>>>>> Another neat property: X is an individual and a class.
>>>>> Now I can ... What?  I don't know.
>>>>> Why do you want to do that?
>>>> How about the example in Section 3.1.3 of the OWL Guide?
>>>> --Frank
Received on Tuesday, 12 August 2008 18:36:43 UTC

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