SUO: Problems in SUMO
After working on OpenCyc for a while, I will
now inquire about some features of SUMO whose
motivation isn't clear to me.
Just one issue for this note. Is there
a need for SUMO to have only two top classes,
"Physical" and "Abstract"? Other ontologies have
more than those two at the top semantic level.
CYC for example, has "PathSystem" which has
both physical and abstract subclasses. Wordnet
has over a dozen top categories. I have over a dozen
in the ontology I am building, such as "Object" which
can have both abstract and physical subtypes.
The point is that there are concepts that have
both Abstract and Physical subclasses, so cannot be
considered either Physical or "Abstract", where
"Abstract" means inheritably abstract. In common
usage, "abstract" merely means "not physical"
but for classes, that should not necessarily
entail that the "Abstract" quality is inheritable.
If SUMO were willing to admit additional classes
into the top level, it could be made more closely
interoperable with other ontologies.
One additional note:
For those who might be tempted to object that
surely all instances of things in the world can
be classified as "abstract" or "physical", I agree.
But that kind of binary classification to generate
a hypercube space of all possible points in
an abstract concept-space is a different sort of
classification from the inheritance hierarchies that
are far and away more typical for ontologies.
The two methods of classification are incompatible
if one wants to view the points in concept space
as classes that are disjoint in any given dimension.
Consider just the "Top" level. That itself is
nether "Abstract" nor "Physical". So why not have
other concepts that are neither?
Pat
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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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