Dear John, (01)
> Some comments on your comments.
> >> The point I was trying to make is that the *metalevel* terms should
> >> be limited to the words used to describe the syntactic units of the
> >> logic
> >> -- eg, 'relation', 'quantifier', 'variable', 'Boolean operator'.
> > As I said repeatedly, a logic, or other formalism for representing an
> > ontology should not make any ontological commitments.
> I completely agree. But the only meaning that the computer can use and
> relate to an application is encoded in the logic. Therefore, any
> discussion about what the computer "knows" or can infer must ultimately
> be related to the logic. Anything else is informal commentary. (02)
> >> But you still have to relate those terms in the upper level ontology
> >> to the words that the domain experts or SMEs use to talk about their
> >> subject. I agree with Doug Lenat that the mid level and lower level
> >> ontology is the most important for applications.
> > Actually it is the other way round. The principle purpose of an upper
> > ontology is that you relate the terms of domain experts and SMEs to
> > that upper ontology together, thereby bringing together similar
> > concepts, and distinguishing different uses of the same terms. You
> > then also apply templates from the upper ontology to the domain terms
> > and improve the consistency of the ontology at the domain level.
> This gets into the issues about how to develop an ontology.
> My recommendation seems to be close to yours: start *middle out* and
> keep iterating until it covers upper, middle, and lower levels. (03)
MW: Yes, that is how I started, but once you have a good upper level
ontology, you just map new stuff too it (and improve it if there are
> By the way, I said that I wasn't going to quibble about the details of
> your terminology. But the word 'class' creates far more confusion than
> it's worth. For example:
> > kind_of_activity
> > A class_of_activity all of whose members are of the same kind.
> Much simpler:
> kind_of_activity: a one-place relation that is true of every activity
> of the same kind. (05)
MW: I disagree. Class_of_activity is the supertype of kind_of_activity, and
you leave no place for it. For end users, class is much easier to relate to
than one place relations, which is a logic view point. I would not with to
burden users with that. I might not choose class if I had my time again, but
in ISO 15926 that is history now, and changing it would be more confusing
than leaving it the same.
> > member_of_ :
> > OPTIONAL SET [1:?] OF class_of_class_of_spatio_temporal_extent; (06)
MW: Now you are looking at a bit of EXPRESS, and you have missed some
important bits. (07)
SUBTYPE OF (class);
member_of_ : OPTIONAL SET [1:?] OF
What this means in plain English is that each
class_of_spatio_temporal_extent may be a member_of_ one or more
> That is an unbelievably complex way to define the basic primitive of
> set theory. (09)
MW: It does not define it. You can look up set theory elsewhere. (010)
Tel: +44 1489 880185
Mobile: +44 750 3385279
This email originates from Information Junction Ltd. Registered in England
and Wales No. 6632177.
Registered office: 2 Brookside, Meadow Way, Letchworth Garden City,
Hertfordshire, SG6 3JE. (013)
Msg Archives: http://ontolog.cim3.net/forum/ontology-summit/
Community Files: http://ontolog.cim3.net/file/work/OntologySummit2013/
Community Wiki: http://ontolog.cim3.net/cgi-bin/wiki.pl?OntologySummit2013
Community Portal: http://ontolog.cim3.net/wiki/ (014)