RE: SUO: RE: CYC event vs. SUMO Process -- really different?
Pat,
You say: "it seems to be agreed that Events have a location in Time".
I am not sure this is the case - as my earlier email hinted at.
Consider the hypothetical Mary's birthday party. Assuming that it does not
have to be on the actual birth-day, then it could be on any number of days -
if she is lucky it could extend over a number of days. This is not a matter
of ignorance or indecision - when considering the hypothetical party we are
considering the possibilities for it. The time has not crystalised. And if
it does not crystallise - i.e. there is no party - we need to explain what
kind of event we are talking about.
This is not a trivial point - but one that makes its appearance (in various
guises) in commercial systems. Consider a financial option. This contracts
for the exercise of an option during a specified period - so there is a
limit on the period, but not a specific time. And this is inherent in the
intention behind the contract.
Does the option contract refer to an event or not? If not, a lot of things
now need a home - if so, then we have to wave goodbye to "Events have a
location in Time".
There is a similar vagueness it seems to me in the boundaries of most actual
events - but that is a different point.
It seems to me that one could sustain the thesis that "Events have a
location in Time" if one stipulated it as a rule - and was prepared to make
the necessary adjustments elsewhere in the scheme. And this may be a good
experiment to try.
But from a more general SUO perspective, I think it will help if the
motivation and consequences of decisions like these are exposed and
discussed. Or, to put it the other way around, one would be foolish to rely
on the SUO if these are not critically reviewed.
I agree with your general point, that we need to try and find some process
for moving forward. But, as Pat Hayes and others said at the begining of
this enterpise, it is not easy. I think this example illustrates the point.
I also was under the impression that John Sowa's proposal was to allow the
various different decisions to live together under one roof so that one
could compare the consequences - if not develop some idea of the motivation.
Regards,
Chris
-----Original Message-----
From: owner-standard-upper-ontology@majordomo.ieee.org
[mailto:owner-standard-upper-ontology@majordomo.ieee.org]On Behalf Of
Patrick Cassidy
Sent: 16 June 2003 17:18
Cc: standard-upper-ontology@ieee.org
Subject: Re: SUO: RE: CYC event vs. SUMO Process -- really different?
I would like try to resolve the specific question of
whether in our standard ontology a 3D Event will
necessarily have a location in Space (it seems to be
agreed that Events have a location in Time).
In John's note he suggests inclusion of both 3D
and 4D events in the ontology. I agree. But I am
unclear as to John's position on the definition
of the 3D Event.
John F. Sowa wrote:
>
> There is no need to vote, when there is a much
> simpler way to accommodate the options.
>
> > What I suggest is that the group forces a vote on
> > important definitions, such as that of "Event."
>
. . .
>
> To take the example of "event", there is no need to
> force a decision. The ontology can simply include
> three types: Event4D, Event3D, and a generic Event,
> which includes Event4D and Event3D as subtypes.
>
OK. These are important issues that we should
proceed to soon. I am only hoping that we can
resolve what should be a simple question before
proceeding to those other issues.
As to the 3D Event, we have an option: is the
spatial location relation marked as "necessary" or not?
If necessary, then every instance of Event in a
knowledge structure will be marked as having *some*
location. That location can be unknown, or default,
or may be specified within the knowledge base.
Can we have both "necessary" and "optional" locations
in one logically consistent ontology? In this case,
I think so, by creating a parent class of 3D Event which
has only a time location ("TemporalEvent"), and a subclass
that has both time and spatial necessary locations
("SpatioTemporalEvent"). But the split 3D Event structure
appears to me to make the translation to 4D more
problematic and I think it should be adopted only if there
is more than one person who thinks it desirable. Also,
it seems to me to be inconsistent with my understanding
of reality and the usual meanings of Events to imagine
that they are not located in space. Even with
spatial location marked as necessary in the SUO,
individual users can still change that to optional
for their own use if such a representation appears to
them to be better, without imposing an unnecessarily
complicated structure on all users.
What I would like to know is how many participants in this
discussion think that the SUO we adopt should have 3D Events
which do not necessarily have some location in Space? Are
there enough to warrant making the SUO more complicated by
addition of an extra "TemporalEvent" class above the more
common "SpatioTemporalEvent"?
Pat
=============================================
Patrick Cassidy
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735 Belvidere Ave. || (908) 668-5252 (if no answer)
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internet: cassidy@micra.com
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