SUO: OpenCyc problems
In response to Eric's suggestion that problems with OpenCyc be
described explicitly:
Eric Peterson wrote:
>
> I could have easily missed some, but the only concrete OpenCyc
> criticisms that I have seen surface on this group, I had to
> press for. And they turned out not to be valid.
. . . I will provide one minor example.
There are others. My main concern with OpenCyc is in
what it leaves out, specifically Processes which are a
subclass of functions, and substances which are more abstract
than pieces of a particular substance.
Today's problem is in the definition of "SheetOfSomeStuff"
and its subclass "PortalCovering". The latter is two
levels down the class hierarchy from the former.
The definitions:
#$SheetOfSomeStuff:
OPENCYC 1: MAY 23, 2002
A specialization of #$PartiallyTangible. Each instance of
#$SheetOfSomeStuff is a substance which (in its `intrinsic' shape) is
continuous and, when flattened, uncrumpled, unfurled, etc., has one
dimension which is significantly smaller than the other two
dimensions. The requirement of being a continuous sheet does not
preclude some type of penetrability, as in instances of #$Screen-Mesh,
#$Netting, or #$LaceCloth. Instances of #$SheetOfSomeStuff may be in
solid, liquid, or gaseous form. An instance of #$Puddle on a
relatively flat surface (but not in a deep pothole) or an instance of
#$AltoStratusCloud would be members of this collection. Note that
being an instance of this collection implies nothing about the current
configuration of the instance; in particular, instances of
#$SheetOfSomeStuff need not be lying flat. For example, aluminum foil
on a roll or a bedspread crumpled up on a bed are instances of
#$SheetOfSomeStuff. Cf. #$SheetShaped, #$TwoDimensional.
#$PortalCovering
OPENCYC 1: MAY 23, 2002
A specialization of #$SolidTangibleThing. Each instance of
#$PortalCovering is a solid tangible object that covers a portal.
Instances of #$PortalCovering may be either flexible or rigid, and
they may be either fixed in place or removable. Examples include
windows (in buildings or automobiles), doors, shutters, screens,
draperies, window blinds, convertible tops, lids, and corks.
. . . and #$Portal itself:
OPENCYC 1: MAY 23, 2002
The collection of all openings, as in a surface, through a tube, etc.,
with or without a covering. This includes doors, mouths,
doughnut-holes, etc.
Notice that the #$PortalCovering is intended to include corks
(coverings for bottle portals), But a cork doesn't fit the
criterion for SheetOfSomeStuff (which is a very useful concept).
So it shouldn't be a subclass. #$Cork itself doesn't appear
in OpenCyc (at least the version I looked at six months ago).
I suspect that the concept of "Portal" is just too overbroad
in OpenCyc and could usefully be subdivided into portals in
rooms in a structure (which are planar) and other kinds of
portals, like those in containers (corks, stoppers in a flask,
spigots on the end of a pipe, etc.) Then #$PortalCovering would
also be divided. Perhaps Cyclists find the very broad
#$PortalCovering to be useful, but I can't think of a situation
where I would want to cover all those very different cases
at the same time. An example of where the general case is
actually useful would help.
Pat
=============================================
Patrick Cassidy
MICRA, Inc. || (908) 561-3416
735 Belvidere Ave. || (908) 668-5252 (if no answer)
Plainfield, NJ 07062-2054 || (908) 668-5904 (fax)
internet: cassidy@micra.com
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