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RE: SUO: RE: A proposed SUO content outline - location





(This is reply is quite delayed because of interruptions.  Still, I wanted
to get on the record.)

Chris,

Good questions.  I've clearly been guilty of (a) assuming people
would understand what I thought I meant when I didn't explain
myself, and (b) vague thinking I wasn't completely aware of.

See embedded comments below.

Regards,

John Velman

>Please respond to Chris Partridge <chris_partridge@csi.com>
>Sent by: owner-standard-upper-ontology@ieee.org
>To: John.Velman@HSC.com, standard-upper-ontology@ieee.org
>cc:
>
>Subject: RE: SUO: RE: A proposed SUO content outline
>
>
>
>John,
>
>I happen to agree with your position.
>But it needs to made clearer.
>Are these 'things':
>1) physical objects or do they include
>2) regions of space-time, where these are not physical objects.
>If you allow 2), as many people do, then every physical thing occupies a
>space-time region (or space region, or whatever your view of space-time
>is).
>This abundance is why I favour a version of option 1).
>

The short answer is (1 - physical objects).  But of course this requires a
little more explanation.  Often when we give locations of things we do this
in terms of coordinate systems of some kind.  I think coordinate systems
are abstract (but are encoded in physical objects in some way, in order to
be useful).  However, I think coordinate systems themselves are, let me
say, "anchored" by identifiable aspects of physical things.  So when I said
that "it is fundamental that things don't have locations.  They only have
locations _relative_ to other things." I was speaking very loosely (blush),
and the dependence may be rather indirect through a chain of abstractions.

(By the way  Shape of Space - Graham Nerlich that you
referred me to earlier has been shipped, but hasn't
arrived yet.)

I know this is stated roughly, and is going to take some time to work out.
Probably should be deferred till we start dealing seriously with
measurements and coordinate systems.

>However, I think it makes sense to agree on the ontological architecture -
>vis a vis space and time - BEFORE discussing location. Or using location to
>clarify what choice of ontological architecture on is going to make.
>

It certainly influences the way you talk about them!  Certainly, one should
have an architecture in mind (and express it clearly) before discussing
location.

>Regards,
>Chris
>
>-----Original Message-----
>From: owner-standard-upper-ontology@ieee.org
>[mailto:owner-standard-upper-ontology@ieee.org]On Behalf Of
>John.Velman@HSC.com
>Sent: 27 February 2001 22:27
>To: standard-upper-ontology@ieee.org
>Subject: RE: SUO: RE: A proposed SUO content outline
>
>
>
>
>I've snipped most of the following, and left only the snippet I want to
>comment on
>just now.
>
>It seems to me that it is fundamental that things don't have locations.
>They only
>have locations _relative_ to other things.   (This harks back to John
>Sowa's list
>of coordinate systems or coordinate free alternatives of a day or so back.)
>
>There is a function  underlying _where_ that is a binary function, for
>example,
>                separation(x,y).
>
>(Sorry, I can read some KIF but can't write it yet.).
>
>Then there would be functions from whatever is in the range of _separation_
> to the real numbers,  so we would have, for example,
>                  miles(separation(me,home))= 15.
>
>It isn't too far from here to being able to define coordinate frames.
>I'll try
>to put some rigor behind this as an exercise for myself.
>
>Similar comments apply to the time dimension.
>
>John Velman
>
>
>
>
>
>
>Ian Niles <iniles@teknowledge.com>@ieee.org on 02/27/2001 12:07:43 PM
>
>Please respond to Ian Niles <iniles@teknowledge.com>
>
>Sent by:  owner-standard-upper-ontology@ieee.org
>
>
>To:    standard-upper-ontology@ieee.org
>cc:
>
>Subject:  RE: SUO: RE: A proposed SUO content outline
>
>
>
>.....
>
>OK, this sounds like a good name, and I like the idea of a function from
>things to their locations.  Note though that the two functions won't be
>exactly analogous, since the locative function will require an extra
>argument, viz. a point in time or a time interval.
>
>
>