First of all, apologies to all for the unfortunate header on
my previous message – I’m a bit out of practice posting to lists
like these, and I’m receiving this list in digest form (which actually I’m
finding a bit confusing, I might change that).
Thanks, Chris, for the reminder about CL, with which I’m
familiar. Following Leo – yes, what was concerning me was issues of
inference engine design qua changeable arities. It just sounded to me like a
recipe for chaos (just imagining the kind of backchaining that might result….!!!)
The suggestion was made that Bundy was envisaging a system involving a
metalevel of reasoning whereby changes to the formalism itself would be applied
at that level following some independent set of heuristics. I wouldn’t
want to rule that out in principle but would love to hear some actual details
of rules which might be applied at that level.
There was a post by Barry Smith which I would’ve liked
to read but it got scrubbed in my digest due (I think) to being in HTML –
I don’t suppose it could be re-posted?
John I was interested to read your description of your
evolution away from advocating axiom-rich ontologising towards recommending
something much closer to Wordnet, indeed a system where (if I have it right) the
only assertions in the ontology are purely definitional, concerning the
meanings of terms, and no empirical claims are made. This sounds prima facie plausible.
However, can a sharp distinction be made between these two categories of claim?
I don’t think so. I think that is one of the lessons of Peirce’s
pragmatism. Consider for instance, “Electrons have a negative charge”.
This was an empirical claim at some early stage of atomic theory yet is now
analytically true. “Cats have whiskers” – empirical or
definitional?
Also, when you say that assertions in any upper ontology are
“much less important” than assertions in lower-middle and domain
ontologies I think that this statement equivocates dangerously on 2 different
meanings of “Much less important”:
i) Much fewer ontologist working hours are spent on this
part of the ontology (true)
ii) Removing or changing these assertions breaks or
changes less (false!!)
I can remember quite a few times when I was working at Cycorp
that relatively minor changes made at the upper level had (rather fascinatingly)
unintended consequences for folks working on specific projects. (To give just
one example, ‘person’ (the legal – social entity) was
separated out from ‘human being’ (the species) and various inferences
which depended on those two concepts being munged together then broke….)
Cheers,
Cathy