Re: Principles of ontology

Michael Uschold (
Fri, 5 Dec 1997 13:26:33 -0800

General Comments:

I belive John has done a good job of clarifying some issues, and barring
relativaly minor details, I am in agreement with most of his terms and


I was surprised to see PROTOTYPE ONTOLOGY as a major ontology type, however,as
I am not familiar with many examples of this sort of ontology. Can anyone name
a few and/or give references? If there are not many, then it does not seem
appropriate to highlight this as a major type of ontology.

> The subject of _ontology_ is the study of the _categories_ of things
that exist or may exist in some domain.

As the term has been used in the so called ontology community, I would say that
of equal importance to _categories_, are _relationships_. The above definition
does not seem to include this, though it is mentioned later. I would suggest making it more prominent initially by adding to the opening as follows:

... that exist or may exist in some domain, and the relationships that may
exist between things in those categories.

> KNOWLEDGE BASE. An informal term for a collection of information that
> includes an ontology as one component.

An ontology is *sometimes* a component of a KNOWLEDGE BASE, but not always.
Sometimes, an ontology is used to structure a KB, but is not actually
part of it. This is clearly explained in a Kactus project report.

Mike Uschold