ontolog-forum
[Top] [All Lists]

Re: [ontolog-forum] Thing and Class

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: "John F. Sowa" <sowa@xxxxxxxxxxx>
Date: Tue, 09 Sep 2008 08:48:49 -0400
Message-id: <48C670B1.20408@xxxxxxxxxxx>
Dear Matthew,    (01)

Whether you have a 3D or a 4D perspective, change still exists,
and the distinction between extension and intension is still
significant.    (02)

JFS>> But even for a fixed design, the set changes with every instance
 >> that rolls off the assembly line.    (03)

[MW] Only if you take a 3D perspective which sees what exists as
What exists NOW.    (04)

In any perspective, you must be able to plan for the future, talk
about what exists NOW, or what exists in some hypothetical time
or place that might never exist anywhere in the 4D universe.    (05)

You must also be able to talk about hypotheticals that could have
existed in the past when you're carrying out a forensic investigation
about how some situation at some point in time and place happened
to evolve out of some other situation at some other time and place.    (06)

JFS>> You can't use extensional terms such as 'set' and 'class', which
 >> change with every instance that rolls off the assembly line.
 >> It's essential to use intensional terms, such as 'category' or
 >> 'type'.  Since 'type' takes one syllable instead of four, that
 >> is a good choice.    (07)

[MW] But you can if you are a 4-dimensionalist.    (08)

A 4D world view does not preclude change.  The fundamental laws of
physics are stated as partial differential equations that vary
in the spatial coordinates and the time coordinate.    (09)

So you can and must be able to think, talk, and plan for change
in our actual universe.  You must also be able to talk about the
hypothetical aspects of the universe that might or might not exist
in any region of the actual universe.    (010)

Bottom line:  The distinction between extensions and intensions is
independent of any coordinate system or point of view.  It is
fundamental to any theory, language, or logic for ontology.    (011)

John    (012)



_________________________________________________________________
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    (013)

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