General Formal Ontology (GFO)
Above we have presented two ways of classifying processes, first into
as either discrete or continuous, and second as either simple or complex processes.
However, neither is well suited as a general process
classification, because the first case is a relative notion, whereas
the second one is very structural in nature and appears useful
from a technical point of view. Philosophical literature offers some
other classifications which we analyze below.
8.4 Process Classifications
Casati and Varzi (16) draw a classical distinction of what they call
events (``things that happen``) between activities,
achievements, accomplishments, and
states20. This classification
is summarized in table 1. The classification criteria
are homogeneity, culmination, and instanteity.
An event is homogeneous if the same description applies to
its sub-events. Culmination is understood as having a natural
finishing point. Instantaneity refers to the duration of the event.
Types of events compiled according to (16)
Obviously, these types involve more kinds of occurrents than only
achievements appear to be extrinsic changes, as they are assumed to
happen instantaneously. The choice of extrinsic changes, as opposed to
intrinsic, is based on the notion of culmination which seems to refer
to a realizable difference. States, as defined by Casati and Varzi (16)
seem to refer to the realm of relations and facts, since there
are no changes (in an intuitive sense) involved.
What remains are achievements and accomplishments, which are at least
extended in time like processes. However, we doubt that these are an
adequate classification of processes due to relying on the notion of
homogeneity. Homogeneity is not a property of a process individual,
but it is a property of some process universal,
like walking. Neglecting granularity aspects, one can agree that all
temporal parts of an individual walking are also instances of
walking. However, this is not a property of the individual. For
instance, we may extend the description to ``John walks
from to .'', which still refers to a walking, but more precisely to
a walking from to . The latter is no longer homogeneous, but it has
the same instance.
Culmination allows for a similar argument. It seems to be based
on identifying what can be derived at the end of the process. A
culminating event is associated with an end point. This does not mean,
however, that a non-culminating event does not have an end point. Each
walking of John finds an end, and could thus also be
classified as an accomplishment in the form, John walked to .
For the above reasons, we refrain from accepting the distinction
between achievements and accomplishments as a classification for
process individuals, although we acknowledge that these terms refer
to process universals. Note that difficult questions of the identity of
processes touch the issues just discussed. Nevertheless, we
will not address such issues, as they are not in the focus of this