Re: [OEP] Review o Time Ontology editor's draft 18 April 2006

Guus,

Thanks again for the suggestions.

We will replace "begins" and "ends" with "hasBeginning" and "hasEnd"
in the OWL version of the ontology, to conform to OWL convention.

(In the full theory, we will keep "begins" and "ends" but introduce
two new predicates "hasBeginning" and "hasEnd", with the trivial
definitions

     hasBeginning(T,t) <--> begins(t,T)

simply because to do a global replacement would be too extensive.
But that shouldn't upset the OWL community.  Only the "hasX" predicates
will appear in OWL.)

On the relation between intervals of zero length and instants, that's
a deep issue that we would rather avoid if possible.  I guess we could
say something like

"It is generally safe to think of an instant as an interval with zero
length, where the beginning and end are the same."

 > - In the Time ontology there is no way to "describe" Instants. You can
 > only approximate them by inDateTimeDescription (or "inside").

We will add something like

"With inDateTimeDescription you do not describe instants; you only approximate
them by confining them within an interval.  This should generally be adequate.
Where it is not, you can always define an instant in a roundabout way as the
beginning of an interval."

-- Jerry