Yesterday, I posted the quick private note on cartoon laws of physics
to Klaus and Keith. Keith, a Socratic provocateur and corrupter of
youth, suggested that I post it to the list. Seduced by the lure of
cheap thrills, I succumbed to the Wizard from Oz and did so.

While I had not intended to enter the thread, I will make amends for
my post by offering a few resources that may shed light on the
different positions in the thread.

The term ontology is used in different ways today, each arising from
earlier traditions.

The original root of the term "onto" supports both uses:

According to the Oxford English Dictionary, the prefix "onto-"
combines "form of Gr. , - being present participle of to be. ontogony
[- generation, production], the history of the production of
organized beings (Mayne Expos. Lex. 1857). ontography [-GRAPHY], a
description of the nature and essence of things (Mayne); so
ontographic a. ontonomy [- distribution, arrangement] (see quot.).
ontosophy [ wisdom], the knowledge of being; ontology. ontotheology
(see quots.); so ontotheological a. 1803 J. STEWART (title) Opus
maximum..*Ontonomy; or, the science of being. -- 1727-41 CHAMBERS
Cycl., Ontology, or *Ontosophy, the doctrine or Science de ente, that
is, of being, in the general, or abstract. 1869 Contemp. Rev. X. 407
It was not to be an 'ontology' nor an 'ontosophy'. -- 1798 A. F. M.
WILLICH Elem. Critical Philos. 171 *Ontotheology is the cognition of
a Supreme Being from bare conceptions. 1854 GEO. ELIOT tr.
Feuerbach's Essence Christianity ii. 38 The ens realissimum, the most
real being of the old onto-theology. -- Ibid. 40 The
*onto-theological predicates are merely predicates of the
understanding" (OED Online 2002: unpaged).

The OED describes the suffix "-logy" "earlier written -logie, an
ending occurring originally in words adapted from Gr. words in - (the
earliest examples, e.g. theology, having come through F. -logie,
med.L. -logia). These Gr. words for the most part are parasynthetic
derivatives; in some instances the terminal element is word,
discourse (e.g. in tetralogy, trilogy); more commonly it is the root
- (ablaut-variant of -, to speak: cf. LOGOS). In the latter case, the
ns. in - usually denote the character, action, or department of
knowledge proper to the person who is described by an adj. or n. in
-, meaning either '(one) who speaks (in a certain way)', or '(one)
who treats of (a certain subject)'. Hence the derivatives in - are of
two classes, (1) those which have the sense of 'saying or speaking',
examples of which are the words anglicized as battology, brachylogy,
cacology, dittology, eulogy, palillogy, tautology; and (2) names of
sciences or departments of study. As the words of the last-mentioned
class have always a n. for their first element, and o is the
combining vowel of all declensions of Gr. ns., the ending of these
compounds is in actual use always -, becoming -OLOGY in Eng. The
names of sciences with this ending are very numerous: some represent
words already formed in Gr., as theology, astrology; many represent
formations which might legitimately have existed in Gr., as geology,
zoology, psychology; others are of hybrid composition, as sociology,
terminology, insectology. The modern formations in -logy follow the
analogy of Gr. formations in having o as the combining vowel;
exceptions are petralogy (an incorrect form which some writers prefer
to petrology because it shows the derivation from rock, not from
stone) and mineralogy (F. minéralogie) which may be viewed as a
contraction for *mineralology. The suffix -ology is freely used in
the formation of humorous nonce-wds., some of which are illustrated
below. All the modern formations in -logy may be said to imply
correlative formations in -LOGICAL and -LOGIST; in the case of some
of the older words, the related personal designation ends in -LOGER
or -LOGIAN. (Cf. -LOGUE.) Hence logy nonce-wd. = OLOGY. 1820 W.
BUCKLAND in Mrs. Gordon Life (1894) 40 Having allowed myself time to
attend to nothing there but my undergroundology. 1837 Fraser's Mag.
XV. 360 Hats were of scientific importance in his estimation, he had
originated a system of hatology. 1853 (title) Chapology, or Hints
about Hats. 1856 J. YOUNG Demonol. IV. iii. 372 The many Logies and
Isms that have lately come into vogue. 1891 T. HARDY Tess (1900) 49/1
What are called advanced ideas are really in great part but..a more
accurate expression, by words in logy and ism, of sensations which
men and women have vaguely grasped for centuries" (OED Online 2002:
unpaged).

While the prefix and suffic roots support both uses seen here, OED's
definition of ontology tends toward the classical usage: "The science
or study of being; that department of metaphysics which relates to
the being or essence of things, or to being in the abstract. 1721
BAILEY, Ontology, an Account of being in the Abstract. 1724 WATTS
Logic I. vi. §9 In order to make due enquiries into all these, and
many other particulars which go towards the complete and
comprehensive idea of any being, the science of ontology is exceeding
necessary. This is what was wont to be called the first part of
metaphysics in the peripatetic schools. 1733 (title) A Brief Scheme
of Ontology or the Science of Being in General. 1776 ADAM SMITH W.N.
(1869) II. V. i. 355 Subtleties and sophisms..composed the whole of
this cobweb science of ontology, which was likewise sometimes called
metaphysics. a1832 BENTHAM Fragm. Ontol. Wks. 1843 VIII. 195 The
field of ontology, or as it may otherwise be termed, the field of
supremely abstract entities, is a yet untrodden labyrinth. 1865
Reader 8 July 30 We cordially approve and admire,..not least, the
signal demolition of Ontology, in the form of the noumenon, or
unknowable substratum of matter and mind. 1884 BOSANQUET tr. Lotze's
Metaph. 22 Ontology..as a doctrine of the being and relations of all
reality, had precedence given to it over Cosmology and Psychology,
the two branches of enquiry which follow the reality into its
opposite distinctive forms" (OED Online 2002: unpaged).

In contrast, Merriam-Webster gives a concise definition of the term
ontology to suppport both uses seen here: "on·tol·o·gy Pronunciation:
än-'tä-l&-jE Function: noun Etymology: New Latin ontologia, from ont-
+ -logia -logy Date: circa 1721 1 : a branch of metaphysics concerned
with the nature and relations of being 2 : a particular theory about
the nature of being or the kinds of existents" (Britannica Webster's
2002: unpaged).

Good short articles on the term can be found in Bunge (1999: 200-201)
Mautner (1996: 304), and especially in Francois (1997: 251-252).
Francois's discussion of what Maturana labeled "constitutive
ontology" comes closest to the use of the term ontology as
represented by cartoonists or science fiction writers who invent
worlds complete with the rules of existence that constitute the
reality of the worlds they invent.

The web site of the Stanford University Knowledge Systems Laboratory
(KSL 2001) offers a good overview of current uses of the term
ontology. In an article titled, "What is an ontology?", Tom Gruber
(2002: unpaged) gives a short answer, "An ontology is a specification
of a conceptualization."

In elaborating, Gruber (2002: unpaged) covers some of the issues that
have come up here. He also distinguishes the current usages of the
term from what the term means in general philosophy:

"The word 'ontology' seems to generate a lot of controversy in
discussions about AI. It has a long history in philosophy, in which
it refers to the subject of existence. It is also often confused with
epistemology, which is about knowledge and knowing.

"In the context of knowledge sharing, I use the term ontology to mean
a specification of a conceptualization. That is, an ontology is a
description (like a formal specification of a program) of the
concepts and relationships that can exist for an agent or a community
of agents. This definition is consistent with the usage of ontology
as set-of-concept-definitions, but more general. And it is certainly
a different sense of the word than its use in philosophy.

"What is important is what an ontology is for. My colleagues and I
have been designing ontologies for the purpose of enabling knowledge
sharing and reuse. In that context, an ontology is a specification
used for making ontological commitments. The formal definition of
ontological commitment is given below. For pragmatic reasons, we
choose to write an ontology as a set of definitions of formal
vocabulary. Although this isn't the only way to specify a
conceptualization, it has some nice properties for knowledge sharing
among AI software (e.g., semantics independent of reader and
context). Practically, an ontological commitment is an agreement to
use a vocabulary (i.e., ask queries and make assertions) in a way
that is consistent (but not complete) with respect to the theory
specified by an ontology. We build agents that commit to ontologies.
We design ontologies so we can share knowledge with and among these
agents."

This definition is found in Gruber (1993), from an artiucle he
published in the journal Knowledge Acquisition.

Gruber also provides a useful excerpt from another article,

"Ontologies as a specification mechanism

"A body of formally represented knowledge is based on a
conceptualization: the objects, concepts, and other entities that are
assumed to exist in some area of interest and the relationships that
hold among them (Genesereth & Nilsson, 1987) . A conceptualization is
an abstract, simplified view of the world that we wish to represent
for some purpose. Every knowledge base, knowledge-based system, or
knowledge-level agent is committed to some conceptualization,
explicitly or implicitly.

"An ontology is an explicit specification of a conceptualization. The
term is borrowed from philosophy, where an Ontology is a systematic
account of Existence. For AI systems, what "exists" is that which can
be represented. When the knowledge of a domain is represented in a
declarative formalism, the set of objects that can be represented is
called the universe of discourse. This set of objects, and the
describable relationships among them, are reflected in the
representational vocabulary with which a knowledge-based program
represents knowledge. Thus, in the context of AI, we can describe the
ontology of a program by defining a set of representational terms. In
such an ontology, definitions associate the names of entities in the
universe of discourse (e.g., classes, relations, functions, or other
objects) with human-readable text describing what the names mean, and
formal axioms that constrain the interpretation and well-formed use
of these terms. Formally, an ontology is the statement of a logical
theory.

"We use common ontologies to describe ontological commitments for a
set of agents so that they can communicate about a domain of
discourse without necessarily operating on a globally shared theory.
We say that an agent commits to an ontology if its observable actions
are consistent with the definitions in the ontology. The idea of
ontological commitments is based on the Knowledge-Level perspective
(Newell, 1982) . The Knowledge Level is a level of description of the
knowledge of an agent that is independent of the symbol-level
representation used internally by the agent. Knowledge is attributed
to agents by observing their actions; an agent "knows" something if
it acts as if it had the information and is acting rationally to
achieve its goals. The "actions" of agents---including knowledge base
servers and knowledge-based systems--- can be seen through a tell and
ask functional interface (Levesque, 1984) , where a client interacts
with an agent by making logical assertions (tell), and posing queries
(ask).

"Pragmatically, a common ontology defines the vocabulary with which
queries and assertions are exchanged among agents. Ontological
commitments are agreements to use the shared vocabulary in a coherent
and consistent manner. The agents sharing a vocabulary need not share
a knowledge base; each knows things the other does not, and an agent
that commits to an ontology is not required to answer all queries
that can be formulated in the shared vocabulary.

"In short, a commitment to a common ontology is a guarantee of
consistency, but not completeness, with respect to queries and
assertions using the vocabulary defined in the ontology."

In a footnote, Gruber (2002: unpaged) adds that "Ontologies are often
equated with taxonomic hierarchies of classes, but class definitions,
and the subsumption relation, but ontologies need not be limited to
these forms. Ontologies are also not limited to conservative
definitions, that is, definitions in the traditional logic sense that
only introduce terminology and do not add any knowledge about the
world (Enderton, 1972) . To specify a conceptualization one needs to
state axioms that do constrain the possible interpretations for the
defined terms."

It seems to me that this view supports Klaus's perspective on the
usage of the term ontology. (This is also related to Brian Prasad's
notes on knowledge-based systems. I appreciated what Brian wrote. In
seeking clarity on the meaning of knowledge, I intended to
distinguish between what may be known by a conscious knowing agent
and those kinds of knowledge that may be supported by a mechanical
device. It is clear that KBS technology may generate new and
surprising information that does, indeed, constitute new knowledge
when embodied by a conscious knower, but it does not become knowledge
as I define it until a knowing agent [knows] it. I bracket the term
know purposely to acknowledge that this is a delicate term and to
avoid starting a new thread on what it is to [know].)

Three outstanding web resources on the theme of ontology provide
further information for those who are interested.

Raul Corazzon provides a Web site titled Descriptive and Formal Ontology at URL

http://www.formalontology.it/

This is a massive web site with myriad features includes articles,
bibliographies, links, readings, on-line papers, and a vast array of
well structured materials.

Corazzon continually updates the site. For example, he recently
posted a synthesis of search engine results on important
philosophical themes in ontology, and he has marvelous collections of
current web site on ontology, metaphysics, artificial intelligence,
and related themes.

A non-profit organization called KR, Inc. - Principles of Knowledge
Representation and Reasoning, Incorporated - hosts a site titled The
Ontology Page at URL:

http://www.kr.org/top

The Ontology Page attempts to function as a world-wide resource on
"activity aimed at developing formalized ontologies as the basis for
shared and modularly-structured knowledge. TOP covers every aspect of
work on ontologies, including the construction, specification,
formalization, representation, analysis, and documentation of
ontologies, as well as their use at all levels in communication,
computation, and reasoning."

Finally, in the classical philosophical context, the Department of
Philosophy at State University of New York, Buffalo, provides a web
site on ontology known as the Buffalo Ontology Site. The Buffalo
Ontology Site provides information on ontology, history of ontology,
and contemporary ontology along with links to other sites on the
topic.

The URL is: http://ontology.buffalo.edu/

And now, my ontological mission complete, I retire once again.

It is Pinseafton here in Sweden, the day before Pentecost. While we
watch Donald Duck - Kalle Anka - on Julafton, Christmas Eve, I am sad
to say that there is no Daffy Duck equivalent for Pentecost. This is
a shame, for Daffy somehow exemplifies the moment when Matthias
joined the eleven apostles, and "a sound like the blowing of a
violent wind came from heaven and filled the whole house where they
were sitting." (Acts 2: 2). Daffy's inventive pranks often speak with
tongues of fire, and the laughter of invented worlds causes us to ask
as the amazed and bewildered crowds asked, "What does this mean?"
(Acts 2: 12).

While Daffy will not be visible, Danish TV 2 is broadcasting a
classic Burt Kennedy Western starring Willie Nelson, Richard Widmark,
and Jack Elam. It's titled "Den sidste desperado" in Danish, but it
is actually the movie known to all you cowboys and cowgirls as "Once
Upon a Texas Yrain."

This afternoon will find me glued to the screen as I iron. Although
the Wizard from Oz has done his best to corrupt me, I remain a duktig
svensk hemmeman, devoted to home, and laundry while dreaming about
life as a gunslinger in the old West. Now THAT is ontological
commitment!

Ken Friedman



References

Britannica Webster's. 2002. Encyclopedia Britannica Online.
Merriam-Webster's Collegiate Dictionary. Online edition. Chicago:
Encyclopedia Britannica, Inc. URL: http://www.britannica.com/. Date
accessed: 2002 May 18.

Bunge, Mario. 1999. The Dictionary of Philosophy. Amherst, New York:
Prometheus Books.

Francois, Charles. 1997. International Encyclopedia of Systems and
Cybernetics. Munich: K. G. Saur.

Gruber, T. R. 1993a. "A translation approach to portable ontologies."
Knowledge Acquisition, 5(2):199-220.

Gruber, T. R. 1993b. "Toward principles for the design of ontologies
used for knowledge sharing." Presented at the Padua workshop on
Formal Ontology, March 1993.

Gruber, Tom. 2002. "What is an Ontology? URL:
http://www-ksl.stanford.edu/kst/what-is-an-ontology.html. Date
accessed: 2002 May 18.


KSL 2001. Knowledge Systems Laboratory Stanford University. URL:
http://www-ksl.stanford.edu/. Date accessed: 2001 March 12.

Mautner, Thomas. 1996. A dictionary of philosophy. Oxford: Blackwell.

OED. 2002. OED Online. Oxford English Dictionary. Ed. J. A. Simpson
and E. S. C. Weiner. 2nd ed, 1989. Oxford: Clarendon Press. Oxford
University Press. URL: http://dictionary.oed.com/ Date accessed: 2002
May 18.







--

Ken Friedman, Ph.D.
Associate Professor of Leadership and Strategic Design
Department of Leadership and Organization
Norwegian School of Management

Visiting Professor
Advanced Research Institute
School of Art and Design
Staffordshire University