[Opencyc-knowledge] Question on #$Events

[Murray A. <m.a...@op...>]

 From the OpenCyc documentation:
 > #$Event   events    **COMMENT NOT REVIEWED**    **GAFs NOT REVIEWED**
 >   An important specialization of #$Situation-Temporal and
 >   #$IntangibleIndividual (qq.v). Each instance of #$Event
 >   is a dynamic situation in which the state of the world
 >   changes; each instance is something one would say happens.
 >   Events are intangible because they consist of changes per
 >   se, not tangible objects that effect changes. Instances of
 >   #$Event should not be confused with instances of #$TimeInterval
 >   (q.v.). The temporal bounds of events are delineated by time
 >   intervals, but in contrast to events time intervals have no
 >   spatial extent.

I have a question regarding #$Event. I'm trying to differentiate
temporal things that are purely temporal (such as points in time,
start and end dates, time intervals, etc.) from both things that
exist (in time and space), and then events. Of cource, Cyc has a
fairly rich vocabulary for this, but when reading over the docs
for #$Event I note that it says (in that last sentence) that "in
contrast to events time intervals have no spatial extent" which
seems to imply that #$Events must have spatial extent, i.e., that
having spatial extent is the differentiating factor. This seems
strange, in that events include thoughts and other things that
don't have spatial extent.

Is there an easy differentiation between events and time intervals?
My understanding is that an event is a change in state in reality
that has a beginning and an ending time, but I don't see what marks
the difference between that and a simple time interval (or at least
I don't see how to easily state that).

Thanks,

Murray

......................................................................
Murray Altheim                    http://kmi.open.ac.uk/people/murray/
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK               .

                    US STATES OF TERROR ALERT
                         green (low)
                         blue (guarded)
                         yellow (elevated)
                         orange (high)
                         red (severe)
                         purple (pucker)