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Re: Tech Plenary: agenda Best Practices

From: Pat Hayes <phayes@ihmc.us>
Date: Thu, 4 Mar 2004 16:55:28 -0600
Message-Id: <p06001f16bc6d5c285125@[]>
To: "Jos De_Roo" <jos.deroo@agfa.com>
Cc: public-swbp-wg@w3.org

>Just that 'meaning stability'; what do you mean by that ??

Well, its rather vague, but imagine that someone publishes an 
ontology of, say, aircraft, or people, or agent actions and policies, 
and it turns out to be useful so that the concepts in it get used by 
others. Now the originators realize that they want to change 
something. Strict W3C-grade Web etiquette requires that they make no 
change to the document at the published URL. But if they produce a 
new version at a new URL, all the old URIrefs in all the other 
ontologies will need to be upgraded. It seems more reasonable to 
think of a Web ontology as something more like a 'moving resource' 
which can get upgraded from time to time, have bugs fixed, be 
generally made better and so on, and still be the 'same resource' in 
the REST web-architecture sense, just with its state brought up to 
date from time to time. OK, but then what KIND of changes to an 
ontology are reasonable for it to be in some sense the 'same 
ontology' ? Im not sure, but I think the question needs to be 
addressed: and I don't think that 'no changes allowed' is a 
reasonable default. It ought to be more like "barring error 
correction, you can still infer the same stuff you could infer 
before" , maybe. Or perhaps there should be a category of 'moving 
ontology' (? Brentano would have liked this...) which when accessed 
gives you an ontological snapshot of the current state of something 
at the access time (the weather forecast rendered into RDF): those 
would obey different rules as they would be expected to change. (Or 
maybe not: maybe we ought to encourage such moving ontologies to 
invent new properties which once invented are eternal, such as 
...#weather030420041646USCT rather than updating the value of 
#weather, so that a moving ontology is always seen as a growing 
ontology, at least conceptually(?) .)  Maybe there are other kinds 
that one would expect to obey still different rules.  And so on. In 
general, there ought to be something identifiable as 'the intended 
meaning' of the ontology which is stable in some sense and which is 
what one can reasonably expect a given URI to go on identifying. 
This certainly isn't the syntactic form of the document, and it isn't 
going to be the strict model-theoretic interpretation in all cases, 
either. I'm not sure what it is, but I have a hunch we need to figure 
it out well enough to write best practice guides to it.


>Sorry if this is too late for the Cannes discussion.
>My 'top 3' would be:
>1. Tell people how to put RDF/RDFS/OWL onto (or attach it to) a web page so
>that it has some relevance to what is on their web page already (which is
>almost certainly largely HTML). Or at least give them an inkling of an idea
>how to do that and why it might be worth doing. In other words, take on the
>task of the public-rdf-in-xhtml-tf effort and get it done.
>2. Get across the idea that the SW will work best when people use one
>another's concepts rather than invent their own, and tell people how to do
>that. The point of having a topic in a Web ontology is to make
>communication easier for agents. We should be thinking of ways to make this
>easier to do: right now there is very little support. Obviously there
>should be ways to find existing concepts and check them out (to find out if
>they are close you the intended meaning one has in mind, or can be tweaked
>so as to be) but we need also to deal with trust issues: like, to what
>extent am I making my ontology hostage to J's ontology if I use J's
>person-concept? Maybe (??) we need to think about a notion of 'meaning
>stability' analogous to the best-practices rules for keeping URIs stable.
>3. (Hendler's #2 - explain the mess)
>4. Finally, this is a negative suggestion, but I would oppose any attempt
>to tell the world how best to write ontologies; or if we cannot avoid doing
>that, then let the advice be severely pragmatic and free from philosophical
>punditry. There is a lingering (festering?) tendency among some folk to
>want to give instruction from on high to the great unwashed on how they
>should best think and express themselves. Unfortunately this advice is
>similar to most religious doctrine: most of the energy is spent in endless
>debates between rival doctrines, you can find some of it somewhere to
>justify almost any action you want to take anyway, and when the rubber
>meets the road most of it isn't really directly applicable in any case
>without an expert there to interpret it for you.
>The idea that mereology is fundamental, as opposed to simply being a useful
>theory of parthood, is one example of a truly bad piece of ontological
>doctrine. (c.f , from http://esw.w3.org/topic/PartWhole :" The partOf
>relation is one of the basic structuring primitives of the universe"
>Er...nonsense. The relation of PartOf cannot be used to "organize the
>universe", which is why mereology never made it as a serious rival to set
>theory, in spite of Nelson Goodman's strenuous efforts; and probably why it
>plays no role in any of the sciences (Is the magnetism part of the
>magnet?). It also is, arguably, not even a very good model of human
>common-sense intuition, eg people are still arguing about some of Plato's
>examples). Another is the pernicious idea that Clear Thinkers *must* make
>some kind of basic ontological division of the universe into two disjoint
>categories of enduring things and dynamic processes (cf
>ontology.buffalo.edu/smith/articles/SNAP_SPAN.pdf ), and another is the
>slightly barmy idea that modal reasoning is somehow connected with keeping
>your databases up-to-date.
>(By the way, it may be of interest to note that the first two of these both
>have their intellectual roots in the same strand of Polish philosophy from
>the late 1800s in Warsaw, for some reason. It is salutary to try reading
>what the founder, Brentano, actually said. But just because Brentano (
>was confused, there is no reason why the rest of us need to be, a century
>Most of our philosophical ontological ideas have never been seriously
>tested in the real world, and there are almost certainly real,
>hard-to-solve problems out there that we have never thought of before. If
>anything, now that we are asking the planet to do ontology, it might
>behoove us to listen and learn, rather than have the hubris to think we can
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IHMC	(850)434 8903 or (650)494 3973   home
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Received on Thursday, 4 March 2004 17:55:31 EST

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