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Dear colleagues, Interesting discussion. On metaphysics, semantics,
context, ontology etc. we have taken a different route. It serves well in practical information
system engineering and I think it could contribute to the semantic web and
“ontology” in the computer science sense. I’ll provide, from the point
of view of our methods, brief notes on a few of the topics mentioned in the
discussion. I’m sorry that it turns out
to be longer than intended. SEMANTICS: The problem of
meaning requires us to examine the relationships between things A (in the role
of signs) that stand for things B, regarded as objects in the reality that the
sign system can represent. For that
limited problem, we must make a commitment about our understanding of the
reality involved in this meaning relationship. We may need only a limited kind of solution to the
metaphysical issue of ontology. We
accept that limitation. But we do not
accept the limitation that seems to govern the main
body of work on the Semantic Web (OWL-related, for instance) that signs stand
for other signs. We are focused on the
world beyond the signs. ONTOLOGY: For all practical engineering purposes, the
only things that exist do so because a responsible agent can perceive them in
the here-and-now. This Presentist version
of Actualism induces careful examinations of time, signs and responsibility,
among other things. (Computing devices
are not responsible agents.) PERCEPTION: An agent
experiences a continual flux of events and actions which it makes sense of by
discovering invariant repertoires of behaviour that enable it to survive and to
avoid the slings and arrows . . . . (See James Gibson’s Theory of Affordances).
The recognition of affordances can be learned by individuals and evolved by a
species. SUPREME CATEGORY: affordance = invariant repertoire
of behaviour. REALISATION: For an agent, a
thing only exists when that affordance is available or realised and this
entails the coexistence of all its ontological antecedents (see dependency,
below). UNIVERSAL/ CATEGORY: An
affordance, as a recognisable, ‘useful’ ability to employ an invariant repertoire of behaviour (example: walk is usually available to a
person from about 1 year until old age but realised only during some particular intervals). PARTICULAR/ INSTANCE: A
universal (ability) may be realised for many particular, shorter, possibly
overlapping periods within its existence (each time a person walks, for
example, or encounters a dog). The agent may not necessarily be able to discriminate
between those particulars (quite a complex process of discovery). DIRECT KNOWLEDGE: An agent
constructs its own reality by discovering the repertoires of behaviour afforded
by the combined functioning of its own structure and the chaotic world it
occupies. (No simple boundary between
the body and environment of the agent?) ONTOLOGICAL DEPENDENCY: An
agent that realises (has available) a certain affordance may be able to realise
further ontologically dependent affordances. For example Agent upright walk or, for joint affordances Agent (paper [medium] WHILE pencil [tool]) draw Here, draw has two
ontological antecedents; no affordance has more than two. ROLES: Relative to every
realised affordance, every antecedent plays a role. Direct antecedents often have natural
language names (in the example above ‘medium’ is dubious) but, at least, they
have default code names. ONTOLOGICAL/ SEMANTIC SCHEMA:
The schema resulting from the successive application of the ontological
dependency constraint depends on a particular root agent. It imposes tight
constraints on the existence of things in the perceived reality all of which is
the ‘private’ reality of that agent. RESPONSIBILITY: In a
biological sense, an isolated agent is responsible for the affordances it
discovers and is responsible for using them, in that it must endure the physical
and ecological consequences of any behaviour prompted by the affordances it recognises. PRESENT: = the coexistence of
an agent’s affordances. An agent with memory (internally generated and
maintained signs) can transcend its limitation within the present. For any realised affordance, it will remember
(retain a signs for) the periods when it did not exist and for its start and finish events. TIME: The starts and finishes
of realisations, registered with the benefit of memory, begin the development
of a notion of time. Moments of time
exist only semiologically; they cannot be visited for perception as sustained
repertoires of behaviour, as other things are perceived, they can only be
signified before or after their existence. SIGNS: In addition to the
development of memories, agents will evolve the perceptions of signs through
metonymical and metaphorical relations to what they stand for. Agents of the same phenotype will discover
how to share their naturally similar repertoires of signs. SOCIETY: An isolated agent
can construct only a rather limited reality.
That changes when a number of agents collaborate by using signs and
learn the affordances discovered by others while also learning to discover collectively affordances beyond the abilities of any of their individual
members. SEMIOLOGICAL KNOWLEDGE: Supremely
in the case of humankind, a society of agents becomes the effective root agent, creaing the larger reality that its members share.
The Actualist ontology compels one to examine in a thorough and rigorous manner the use of signs for constructing past, future, possible, fictional and various social 'realities'. AUTHORITY: An isolated agent
is the only possible authority for making or recognising any change in its perceived reality. A society, consisting
of many responsible agents, assigns authority to appropriate members as agents who register or decide upon changes. In
many cases, starts and finishes are authorised by norms. The condition that triggers the norm’s
application will distribute authority over possibly many agents who determine
the facts that the condition takes into account. RESPONSIBILITY: In the social
sense, responsibility is the obverse of authority (devolved or usurped) and it
indicates with whom to communicate to obtain information or challenge it. SEMANTIC TEMPORAL DATA BASE: The STDB serves as a symbolic surrogate for
the perceivable reality, each realisation represented by a relational tuple
consisting of identifiers representing surrogate identifier category/ universal first antecedent [second antecedent] start (contemporary realisation) finish (contemporary realisation) authority for start
(agent, norm, speech act) authority for finish (agent, norm, speech act) LANGUAGE: One may make
assertions or ask questions about the subject domain; that requires words,
names or numbers (possibly pictures). These are joint affordances, each
ontologically dependent on the realisation and the relevant language(s) or
register(s) employed by the people using the information. To accommodate different cultures,
expressions may be needed rather than single words to serve some language or
other for various affordances. CONTEXT: Any sentence formed
using the signs associated with the schema and particulars recorded in the STDB
will use operators – WHILE, ORWHILE, WHILENOT, BEFORE etc – that take account
of the start and finish events. The
times or temporal relationships, authorities and the antecedents structures for
all the realisations involved all to the context. Context is limitless, always
extending beyond any degree of formalisation we may achieve. “ONTOLOGY” (in the computer
science sense): The ontological dependency schema, which is very stable (indeed
it displays empirically the properties of a canonical form - always open to refutation), can be developed
gradually by accretion from successive applications. GENERIC-SPECIFIC: The
generic-specific relationships that dominate most Semantic Web “ontologies”
tell us about relationships among certain categories; they are perceptual norms
that summarise other norms – cognitive, deontic or evaluative. Each has a
period of existence with a start, a finish and associated authorities. G-S
relationships included in an ontological dependency schema help to abbreviate it. APPLICATIONS: We use these
ideas for specifying purely human information systems as systems of social
norms, with the ontological dependency schema providing the core of the
perceptual norms. We are now able to generate supporting computer applications for the
human system automatically - still testing the limits. PROJECT: We’d like to
initiate a programme for the incremental development of a public domain “ontology”
based on the concept of ontological dependency. Finance? Any suggestions?
Ronald Stamper
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