ontac-dev
[Top] [All Lists]

Re: [ontac-dev] Type vs. Class -- Please vote

To: ONTAC Taxonomy-Ontology Development Discussion <ontac-dev@xxxxxxxxxxxxxx>
From: "Smith, Barry" <phismith@xxxxxxxxxxx>
Date: Sat, 21 Jan 2006 10:02:36 +0100
Message-id: <7.0.1.0.2.20060121095548.045b5478@xxxxxxxxxxx>

This is the definition of 'class' provided in the W3C glossary    (01)

>class
>
> From RDF Semantics (2004-02-10) | Glossary for this source
>(n.) A general concept, category or classification. Something used 
>primarily to classify or categorize other things. Formally, in RDF, 
>a resource of type rdfs:Class with an associated set of resources 
>all of which have the class as a value of the rdf:type property. 
>Classes are often called 'predicates' in the formal logical literature.    (02)


http://www.w3.org/2003/glossary/keyword/All/?keywords=class    (03)

It seems to me that this definition makes all the mistakes we should 
be trying to avoid (incidentally the treatment of 'type' is even worse).    (04)

1. It confuses meaning ('concept') with referent ('class'/'type') 
with expression or symbol ('predicate').
2. It confuses what is in the syntactic category of a predicate 
('predicate', 'property' ...) with what is in the syntactic category 
of a noun ('class', 'type', ...)
3. It is circular ('a class is a resource of type rdfs:Class').    (05)

The disadvantages of using a disjunctive compromise 'ClassOrType' 
(Compare SUMO's ClassOrSet) are, I think:    (06)

1. That we need both of those terms to refer to different things: 
'class' to the extension, 'type' to that which all the members of the 
extension share in common.
2. Ordinary people will use an ontology only to the degree that it 
contains terms they are already more or less familiar with, and given 
that we are providing definitions of our top-level terms there is no 
reason to invent new coinages.    (07)

BS    (08)

At 07:52 AM 1/21/2006, you wrote:
>Leo,
>
>I'd be satisfied with that solution:
>
>>Personally, I think a better methodology for these problematic
>>terminology aspects is to choose the disjunction:
>>Class OR Type
>>And move on.
>
>Some formalisms, such as OWL, happen to use the word
>"class", other use the word "type", and still others
>may represent either one with a monadic predicate.
>
>We can just let the tools that support those notations
>use whatever terminology is common in the community
>that uses those tools.  The only thing that really
>matters is the choice of a suitable underlying formalism,
>such as Common Logic.
>
>For the recommended user notation, I would suggest a
>version of controlled English.  For example, see the
>summary of Attempto Controlled English (ACE):
>
>    http://www.jfsowa.com/logic/ace.htm
>
>As another very similar example, I wrote a grammar for
>Common Logic Controlled English (CLCE):
>
>    http://www.jfsowa.com/clce/specs.htm
>
>There are many issues concerning human factors and suitable
>tools for supporting such languages, but writing a grammar
>for such a language is a development project, not a research
>issue.
>
>_________________________________________________________________
>Message Archives: http://colab.cim3.net/forum/ontac-dev/
>To Post: mailto:ontac-dev@xxxxxxxxxxxxxx
>Subscribe/Unsubscribe/Config: 
>http://colab.cim3.net/mailman/listinfo/ontac-dev/
>Shared Files: http://colab.cim3.net/file/work/SICoP/ontac/
>Community Wiki: 
>http://colab.cim3.net/cgi-bin/wiki.pl?SICoP/OntologyTaxonomyCoordinatingWG
>    (09)



_________________________________________________________________
Message Archives: http://colab.cim3.net/forum/ontac-dev/
To Post: mailto:ontac-dev@xxxxxxxxxxxxxx
Subscribe/Unsubscribe/Config: http://colab.cim3.net/mailman/listinfo/ontac-dev/
Shared Files: http://colab.cim3.net/file/work/SICoP/ontac/
Community Wiki: 
http://colab.cim3.net/cgi-bin/wiki.pl?SICoP/OntologyTaxonomyCoordinatingWG    (010)
<Prev in Thread] Current Thread [Next in Thread>