[Top] [All Lists]

[ontolog-forum] Ontological correctness

To: "[ontolog-forum] " <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Christopher Menzel <cmenzel@xxxxxxxx>
Date: Wed, 31 Jan 2007 11:40:13 -0600
Message-id: <3F99FD04-4D4F-42C5-8099-836751D08E27@xxxxxxxx>
On 31 Jan, at 10:44 , Pat Hayes wrote:
>> Hi Everyone,
>> ... I do think, though, that some
>> measure of correction of logical constructions is probably also
> necessary,
> Amen to that. But it is very hard to see how this is to be done. I
> REALLY wish there were a nontrivial and useful notion of how to
> measure 'correctness' of an ontology. It is not enough to just say,
> it is correct if it "fits the facts" in some sense, since ontologies
> may be based on very different, possibly mutually contradictory,
> conceptualizations, and yet both fit the facts perfectly well.    (01)

Yes, exactly.  And even the idea that there are theory/ontology- 
independent "facts" relative to which an ontology can be deemed  
correct is a HIGHLY dubious notion.  Granted, there are arguably  
facts that are largely ontology-free, or at least assume a rather  
uncontroversial "commonsense" ontology that we all share in common in  
virtue of being wired in roughly the same ways and speaking a variety  
of languages that seem pretty unproblematically intertranslatable --  
mundane facts about trees, persons, cabbages, kings, etc.  But the  
kinds of facts that can be used to confirm or disconfirm an ontology  
typically *presuppose* large portions of some ontology, typically the  
very one in question.  In the hard sciences, for example, facts about  
meter readings, cloud chamber photographs, what is seen via a  
microscope (let alone an electron microscope) already presuppose a  
huge amount ontological baggage about how the various apparatus work,  
what exactly is being measured, and so forth.  So it is not clear  
that any coherent, objective notion of correctness is possible that  
doesn't already beg a lot of questions.    (02)

Note that I don't at all think that his means that everything is up  
for grabs, or that there is no such thing as a correct, etc.  I just  
don't think there is any ontology-independent way of *establishing*  
it -- it's just not possible, once again, to express the facts an  
ontology is supposed to fit to be considered "correct" without  
already assuming some ontological framework.  And even if we agree on  
a minimal ontology O for expressing a certain base of facts, there  
might, as Pat notes, be ontologies O1 and O2 that extend O in  
incompatible ways but which fit the fact base equally well.  (As Pat  
is well aware, both of these points -- the ontology-dependence of  
"facts" and the possibility of empirically indistinguishable but  
logically incompatible ontologies -- are well known and extensively  
discussed in the philosophy of science, and trace back at least to  
Duhem in the 19th century.  The latter point in particular was  
resurrected most notably by the logician and philosopher W.V.O. Quine  
in the late 20th century.)    (03)

I think there are several more useful notions than correctness that  
might be more productively developed.  More or less of the top of my  
head:    (04)

* Semantic clarity:  Can the proposed concepts of an informal  
ontology be fleshed out rigorously in such a way that information  
expressed in terms of those concepts can be objectively shared and  
reasoned upon?    (05)

* Logical coherence:  Are the various concepts of an ontology (when  
rigorously spelled out) consistent, both individually and jointly?    (06)

* Empirical adequacy:  Relative to some assumed collection of facts  
-- and therefore relative to some assumed underlying O -- is a given  
extension O' of O compatible with that collection of facts?    (07)

* Practical applicability:  Does the ontology serve its intended  
purpose?    (08)

There are surely others, and these could use a lot of tightening up,  
but perhaps they are a reasonable first cut at a list of useful  
evaluative criteria for ontologies.    (09)

Chris Menzel    (010)

Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (011)

<Prev in Thread] Current Thread [Next in Thread>