ontolog-forum
[Top] [All Lists]

Re: [ontolog-forum] Thing and Class

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
Cc: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: leo@xxxxxx
Date: Mon, 15 Sep 2008 00:36:11 +0600 (YEKST)
Message-id: <3183.10.0.2.224.1221417371.mgnwebinterface@xxxxxxxxxxx>
John,
Of course !
> Therefore, a taxonomy defined by intentions is more fine grained
> than a taxonomy defined by extensions, because the sets may blur
> important distinctions in the definitions.
But when to use a Classification System in practice there is a need to use
an extansions (Taxonomy) before detailed examining "intentions"
(properties, merons ). There is a need in Dual approach for Taxonomy -
Meronomy.  Suppose it will be useful to look at this paper of J.Schreider
-
http://home.comcast.net/~sharov/biosem/schreidr/schreidr.html    (01)

Leonid - http://ototsky.mgn.ru/it    (02)

> Azamat and Leonid,
>
> Intensions can be derived from extensions, but the extensions may
> lose or ignore some important distinctions in the definitions.  I
> use the Greek letter delta for a *denotation operator* that maps
> a type t and a world w to the set of instances of t in the world w:
>
>     delta:  Types x Worlds -> Sets
>
> However, the mapping by delta is not one-to-one, since for a given
> world w, the set delta(HumanBeing,w) may be the same as the set
> delta(FeatherlessBiped,w).  Also, delta(t,w) for any type t that
> has no instances in the world w would be the empty set.
>
> Therefore, a taxonomy defined by intensions is more fine grained
> than a taxonomy defined by extensions, because the sets may blur
> important distinctions in the definitions.
>
> Different applications that might use the same taxonomy may depend
> on those distinctions.  For example, a taxonomy for the history of
> proposed airplane designs might have the type FlappingWingAircraft,
> but a taxonomy of airplanes that were actually built and survived
> their first test flight might have no instances.  But a taxonomy
> defined by descriptions (intensions) could be used for both purposes.
>
>  > Accordingly, there is extensional classification, called taxonomy,
>  > and intensional classification, called meronomy, or mereology.
>
> The confusion between those two classifications is usually caused
> by terminologies that make a vague distinction of broader/narrower.
> That distinction should be clarified by using different dyadic
> relations, subtypeOf and partOf, which define distinct partial
> orderings.  Both of them should accommodate hypothetical things
> like unicorns, which have a horn as part, and airplane designs
> that depend on the details of how the parts are assembled.
>
> People might dismiss unicorns as mythical or fictional animals,
> but biologists commonly talk about, describe, and search for
> instances of fossils of hypothetical organisms.  An example
> would be the first tetrapod that crawled out of the water and
> became the ancestor of the amphibians.
>
> John
>
>
> _________________________________________________________________
> Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
> Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
> Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
> Shared Files: http://ontolog.cim3.net/file/
> Community Wiki: http://ontolog.cim3.net/wiki/
> To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>
>
>    (03)



_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (04)

<Prev in Thread] Current Thread [Next in Thread>