Re: A simplistic definition of "ontology" (Eduard Hovy)
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Date: Wed, 4 Oct 1995 14:59:23 -0500
To: (Pat Hayes)
From: (Eduard Hovy)
Subject: Re: A simplistic definition of "ontology"
Cc: (Eduard Hovy),
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I think you are not quite reading all of what I wrote: 

At 4:59 PM 10/4/95, Pat Hayes wrote:
>At  8:41 AM 10/4/95 -0500, Eduard Hovy wrote:
>>  An ontology is a collection of symbols that represent (i.e., name) some 
>>  set of phenomena in the "external world" within a computer (or possibly 
>>  within other, non-implemented, systems, although who knows what that 
>>  would be interesting for).  Typically, the phenomena include objects 
>>  and processes and states, and typically, these entities are related 
>>  among themselves; usually, the ontology names (some of) these relations.  
>I think the issue can be focussed by asking whether it is enough to simply
>*name* the relations, or should we ask an ontology to somehow *specify*

What does "specify a concept" mean, if not just to list the relationships 
of the concept with other concepts?  Trying to define "chair", one talks 
about "functionality" and uses that relationship to link "chair" to "sit" 
or "support", etc.  That's what I meant by "these entities are related 
among themselves".  

>Coming as I do from the 'knowledge representation' (rather
>than the 'glossary') side of the divide, I always wonder just how far away
>the other side can be taken to be. 

I'm not sure I believe in this divide you mention (and tried to define at 
the IJCAI workshop).  It seems to me everyone is trying to do essentially 
the same thing -- come up with a set of representation elements and their 
interrelations (under which I include property constraints, etc., that 
constrain inference, and attached inferences too) -- but those you call 
'glossers' try to do it on a larger but less rich scale (since that's what 
supports their systems) while the 'KRers' do the opposite, for purposes 
of detailed reasoning in small applications and domains.  

>(One obvious answer might be that such a glossary is a useful step along
>the way to creating a true ontology, a kind of ontology-sketch, but I dont
>think that is how the compilers of such glossaries regard them.)

Actually I think it is, certainly for the 'glossers' I talk to.  For example 
no NLP person would claim that a mere taxonomy of symbols was enough; it's 
just that this is what's available at present.  


Eduard Hovy
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