- A distinction between infons, states of affairs, pictural states of
affairs has been drawn. In GFO, only facts existed. In situation
theory all relevant entities were infons. We developed a fine-grained
distinction between the three categories, and supported and justified
this distinction with reference to widely accepted philosophers such
as Wittgenstein and our own argumentation.
- We accounted for the concept that some entity ``can be
comprehended as a whole''. Because barsit referred to situations as
``parts of reality that can be comprehended as a whole'', without
further explanation, and herre2 used the same description,
without giving a sufficient explanation, the clarification of this
concept is one central part of this thesis. We investigated
``comprehension'' in general and comprehension of situoids
specifically. Then we analyzed the part-whole relationship from a
gestalt-theoretical point of view. We believe, this view should be
adopted by the researchers of the GOL-group for their entire work, but
we applied it only to situoids and situations. Finally, we analyzed
the structure of reality, to show, how and in what sense situoids may
be a part of it. We have shown how situoids can be extended to
worlds. Multiple possible worlds arise naturally from our view on
situoids as incomplete parts of reality.
- We showed how to introduce modality into GOL by using methods from
situation theory. Jon Barwise himself showed how modalities can be
introduced into situation theory, and we followed his work in most
parts. Because the category of situoids in the ontology of GOL is one
of the most fundamental, and most of the other entities of concern in
GOL can be embedded in situoids, modality has been introduced in the
entire ontology of GOL when introduced for situoids. As modalities
were missing in GOL until now, we encourage the GOL researchers to use
the results of this thesis to introduce modalities into GOL.
- We accounted for granularity in the domain of situoids and
situations.
- We showed how to use situoid theory for the semantic of natural
language. This has been a classical application for situation theory,
one for which situation theory has been developed, and many
work has been done to refine and improve the work of Barwise and Perry
in this field. We followed a very recent paper on this issue,
devlin1, and the ontology of GOL and the theory on situoids
introduced in this thesis are powerful enough to incorporate the
results of devlin1. Together with the power of a top-level
ontology in the background, an account for natural language semantic
may be given, that is richer than the account given by situation
theory.
- We have shown how to incorporate processes and events into
situoids. This is still a debated issue by the GOL researchers, and
they do indeed disagree with us at this point. They believe that
processes are something different than situoids or states of affairs,
something even more basic. However, we tried to justify our point
of view, and gave examples, which the GOL researches have to
explain. This is not a central issue in this thesis, and the research
on processes and events has been mainly motivated by the lack of a way
of describing processes and events in GOL. So if the GOL researchers
follow a different path than we have done, it is possible to ignore
our statements on these issues entirely.
- We discussed the part-of relationships concerning situoids and
situations, and the relationship between parts and wholes in general.
leechuck
2005-04-19
