


Overview
General Formal Ontology (GFO)

Configurations have a counterpart in the realm of processes,
which we call configuroids.
They are, in the simplest case, integrated wholes made up of
material structure processes and property processes.
Furthermore, there is a category of processes whose boundaries are
situations, and that satisfy certain principles of coherence,
comprehensibility and continuity. We call these entities
situoids; they are regarded as the most complex integrated
wholes of the world. As it turns
out, each of the entities we have considered thus far, including processes, can be
embedded in a situoid. A situoid is, intuitively, a part of the
world that is a coherent and comprehensible whole and does not need
other entities in order to exist. Every situoid has a temporal extent
and is framed by a topoid. An example of a situoid is
``John's kissing of Mary'', conceived as a process of kissing in a
certain environment which contains individuals of the persistants John
and Mary.
Every situoid is framed by a chronoid and a topoid. We use here two
relations , and .
Note that the relation
is equivalent to , since a situoid is a
process. The relations and are different,
though, such that the following relation is satisfied:
.
Every temporal part of a situoid is a process aggregate. The temporal
parts of a
situoid are determined by the full projection of onto a part of
the framing chronoid of . This full
projection relation is denoted by
, where is a situoid,
is a part of the framing chronoid of , and is the process that
results from this projection. Boundaries (including inner boundaries)
of situoids are projections to timeboundaries. We assume that
projections of situoids to timeboundaries, which are denoted by
, are situations.
In every situation, a material structure is contained, and
we say that a presential is a constituent
of a situoid , , iff there is a timeboundary
of such that the projection of onto is a situation
containing .
Situoids can be extended in two ways. Let , be two situoids; we say
that is a temporal extension of , if there is an
initial segment of the chronoid such that the projection of
onto equals . We say that is a structural
extension of if is a
structural layer of (cf. section 8.1). Both kinds of
extensions can be combined to form the more general notion of a
structuraltemporal extension. Reality can  in a sense 
be understood as a web of situoids that are connected by
structuraltemporal extensions. The notion of an extension can be
relativized to situations. Since there cannot be temporal extensions
of situations, an extension of the situation is always a structural
extension. As an example, consider a fixed single material structure ,
which occurs in situation . Every extension of is determined by
adding further qualities or relators to to the intrinsic properties
of . A qualitybundle that is unified by the material structure is
called saturated if no extension of adds new qualities. It is an
open question whether there is an extension of , such that every
material structure in unites with a saturated bundle of
qualities.
A configuroid in the situoid is defined as the projection
of a structural layer of onto a chronoid,
which is a part of the timeframe of . In particular, every
structural layer of is itself a configuroid of . Obviously every
configuroid is a process.
But not every process is a configuroid of a
situoid, because not every process satisfies the substantiality
condition.
We postulate as a basic axiom that every
occurrent is  roughly speaking  a
``portion'' of a situoid, and we say that every
occurrent is embedded in a
situoid. Furthermore, we defend the position that processes should be
analyzed and classified within the framework of situoids. Also, situoids
may be used as ontological entities representing contexts. Developing
a rigorous typology of processes within the framework of situoids is an
important future project. Occurrents may be classified with respect to
different dimensions, among them we mention the temporal
structure and the granularity of an occurrent.
As a final note regarding situoids, configurations, and their
relatives, there are a number of useful, derivable categories. For
instance, one can now define situational histories as histories that
have only situations as their boundaries.
In general, the theory of
these entities is considered a promising field for future research.
Robert Hoehndorf
20061018

