SUO: Re: ontology as science
On Thu, Jun 19, 2003 at 09:09:04AM -0400, Burkett, Bill wrote:
> Perhaps I should have inserted the word "objectively" and said
> "objectively testable".
>
> [John S. wrote:]
> >Every axiom and definition of ontology makes a testable claim
> >about one or more of the following three kinds of things:
> >
> > 1. What is in the world,
> >
> > 2. What do people say about what is in the world,
> >
> > 3. What are the relationships among the things in #1 and #2.
>
> I agree that physical science has developed methods for objectively
> determining "what is in the world" independently of individual
> perspective or time. (And is still refining these methods.) However,
> #2 and #3 will always be subjective and therefore of questionable
> testability from a scientific perspective.
Always? If you say there are flying pigs, there is nothing subjective
about your claim (though of course all sorts of subjective phenomena
might accompany it, e.g., a feeling of absolute certainty as to its
truth; a certain thrill at challenging the dominant scientific opinion
on the matter; etc). As for its testability, it is hard to find a
better example. You either put up your flying pig or enjoy life as a
crackpot.
> >By this criterion, lexicography is a science. It gathers data
> >consisting of word occurrences and the surrounding context, and
> >formulates definitions that cover the data. Those definitions can be
> >tested by anyone else who cares to gather similar data and check
> >whether the definitions apply.
>
> Yes, it would be considered a science because it's dealing with
> lexical symbols as the data under objective analysis. With respect to
> semantics, however, it cannot take into account the semantic drift of
> words in a language as a language evolves over time.
Why not? Is there a lexicographers code that prevents them from
altering a word's definition if its meaning has been observed to have
changed?
> Nor can it take into account different languages except as a distinct
> data sets.
Not clear what you mean by "taking into account". Why don't translation
schemes represent a relevant sense of "taking into account"?
> >That kind of science satisfies the point #2 above, which deals
> >with things that people say about the world. It is true if and
> >only if people do indeed say such things about the world.
>
> I don't think any here is objectively testable. It is all subjective
> and will always be subjective - hence the problem.
You have yet to identify the problem.
> Can you describe any kind of objective test that will succeed or fail
> (unambiguously given any tester at any point in time) that will prove
> that when I say "tree" that there are trees in the world?
Well, of course it won't follow from what you say. But John's point, I
take it, is that the word has a reasonably precise, testable meaning
determined by the "division of linguistic labor" within the scientific
and broader English-speaking community. That there are trees follows
from that meaning together with facts in the world.
> Sense perception might be one such test,
What kind of test is "sense perception"?
> but then I'm left questioning what is a "tree" and what isn't,
But we have very good ways of answering that question. Ask a botonist
or (depending on the type of answer you want) a biologist.
> and where do the boundaries of "treeness" end.
Well, *now* you are talking about vagueness, and that is an issue with
most concepts in the natural sciences, and indeed most concepts in
ordinary langauge. But the fact that a concept has vague boundaries
does not entail that there aren't oodles of clear and obvious instances
of the concept, more than enough to ground meaning sufficiently for us
to be able to communicate, do good science, etc.
> >The kind of science stated in point #1 above is physical
> >science, which has an enormous overlap with ontology. Just
> >look at the information in Cyc, SUMO, and other ontologies.
> >They are filled with testable information about scientific
> >topics.
>
> I agree that point #1 is about physical science, but disagree about
> the enormous overlap with ontology except insofar as ontology is an
> example of #2. Ontologies are not testable (setting aside syntactic
> validity, but we're not talking about that.)
Well, in one (trivial) sense, sure -- if you write a bunch of axioms and
*stipulate* them to be constitutive of the meanings of the terms they
contain, then of course there is nothing to test. But that's not how
typical ontologies are written. Rather, they are designed to capture
and clarify pre-existing meanings, and therefore are subject to very
definite external semantic (as well as pragmatic) constraints, and can
be tested as to their efficacy in satisfying those constraints. If you
write an ontology of liquids that entails that a cup with a hole in the
bottom can hold water, you've got it wrong -- empirically, testably so
-- about either cups, holes, water, or the holding relation.
> The only "test" of an ontology that is of any value is whether or not
> in represents the information that I want my information processing
> machines to deal with ...
I thought you just said ontologies weren't testable. I guess that's why
you put "test" in quotes. But that is disingenuous. Whether an
ontology represents the information it is supposed to is precisely the
most important test an ontology has to pass.
> and whether that representation can be communicated effectively
> with other information processing machines. (And note that the "test"
> is about value to a person, not about whether the tested hypothesis
> succeeds or fails.)
I don't understand. You have a concept FOO in your enterprise that you
want your ontology to represent. Turns out it fails to do so; it
doesn't capture the intended concept. So it objectively failed the
test. Whether or not you still find it valuable is up to you. These
are completely orthogonal issues.
> I still stand by the claim that if it involves semantics - perceivable
> symbols that "mean" something - that it cannot be a science.
You appear to have little (objective) reason for so standing, but that's
your (subjective) choice. ;-)
Chris Menzel