RE: multiple inheritance
Patrick Cassidy writes:
> >> The other main reason for multiple inheritance is to make it easier to
> >> generate agreement on a standard upper ontology.
> > This is totally unsubstantiated. It makes agreement harder if
> > anything, by introducing more and more complex interpretations for
> > the subsumption relation.
> It will be quite impossible to "substantiate" such an expectation,
> without building comparable upper ontologies with and without multiple
> inheritance and then seeing which becomes more widely used --
Being widely used is not a reliable criterion for quality. Some examples:
- Microsoft products are widely used.
- Eiffel is not widely used.
> an unlikely scenario. This expectation is based mainly on discussions with
> individuals who have built ontologies with different structures.
> If everyone else would accept *my* notions of how an inheritance tree
> might be structured, I too might be willing to accept a single-inheritance
> system, but . . .
Very good point.
My observation is, that a principle of lingual radicality [eventually together
with a means of scope alias namespace alias context] very often allows to get
consensus, which otherwise would not have been possible. Unfortunately, the
pieces on which this consensus is then achieved, are mostly very small. To
come back to a size of practical weight, it is required, that you have an
instrument to compose these small pieces in a flexible way. And here I see
multiple inheritance in a much better position than single inheritance.