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7.2 The Analysis of Actualising (Kinesis)
The basic notion of how one event causes another event is rather a complex
one. Normally we think that since events are changes in some object, the
real causal link between events arises from the causal properties of that
object. We saw then in chapter
2,
how some notion of disposition is necessary in order to make
intelligible to production of events by objects, so that the events are
the manifestation of certain dispositions (or the actualising of certain
potentialities) associated with the objects concerned.
The causation of an event by another event is then more an
`instrumental causation' of enabling dispositions (`principal
causes') to operate.
The difficulty with this approach is that is not clear how we should
conceive of substances, and it is even less clear how we should
`associate' dispositions with substances. (In chapter
9
some of these problems of substances will be discussed.)
I am therefore following a different approach, starting from
basic ideas of actuality, potentialities and kinesis (actualising). The
aim is to use these ideas to construct fresh notions of substances and how
they are related to their dispositions.
Let us suppose therefore that one elementary event (instrumentally) causes
another elementary event, and then see how this can come about using the
notions of potentialities and actualising that we have developed. The
causal process can then be `unpacked' into a number of perhaps more
basic notions,
when we follow Leclerc [1972, chs. 25 & 26] in taking modal
considerations seriously. The analysis is summarised as follows.
Suppose an actualising event A, say, causes an actualising event
B.
This causation may be deterministic or indeterministic. Then the fact of
that causation implies

 1.
 that the event B was possible, i.e. that there was a
real possibility for the change,
 2.
 that there must have been a real and active power or
propensity to make B happen rather than remain only possible,
 3.
 that the power or propensity must at least have been directed
to the occurrence of B,
 4.
 that there was a set of possibilities for the change. This
set may have members apart from the possibility for B, and its members
form a `spacetime' of possibilities for change, only one of which
actually occurs,
 5.
 that these various possibilities are related to each other in
some structure, and
 6.
 that there was a form of distribution of the power or propensity
over the set of possibilities, since, in general, not all
possibilities are equally likely.
 7.
 that once one possibility is actualised, there is a corresponding
restriction of the distribution of propensities for subsequent
actualisations.
C.
For example, suppose event A is the actual emission of a electron from
a negatively charged cathode, and event B is its definitely hitting and
exposing a grain on a photographic plate. (Whether these events will
in fact be actual will be discussed in chapter
11.)
Then

 1.
 there must have been a possibility for the electron to hit the
photographic plate, and
 2.
 there was a electrostatic propensity to repel the electron, rather
than let it stay where it was when emitted. The electron and the
photographic plate had propensities to interact with each other, rather
than simply pass through each other unchanged.
 3.
 The propensities of (2) are all propensities for the named
occurrences (repulsions and interacting, respectively),
 4.
 if there are quantum effects in the electron's travelling, and
these are objectively random, there are a large number of possibilities
for the interaction B, as it can at least occur at different positions
on and in the photographic plate, and at different times, and
 5.
 these different places are related by being in a fourdimensional
`spacetime', this being the combination of different positions in
the threedimensional volume of the plate with different (one dimensional)
times. These places have metric distances from each other, and temporal
intervals between them.
 6.
 These different places each have their own propensity (and hence
probability) for being where B actually happens. The distribution is
given from the quantum mechanical wave function
as
.
 7.
 There is a `reduction of the wave packet' to (within) the extent
of one photographic grain.
These implications are intended as the necessary components of a general
framework of causation which allows for both deterministic and
indeterministic laws of succession. They are clearly not a
sufficient set of rules for causes, as we have not said (a)
whether there was any means to decide which outcome would actually occur,
nor (b) whether there was any `end' or `purpose' that could be said to be
`satisfied' by the result of the change. It seems that there are neither
`means to decide outcomes' nor `ends satisfied' for physical processes (in
contrast to typical mental processes). Neither have we specified any
mathematical or physical law which gives the precise form of distribution
over the set of possibilities.
Next: 7.3 Kinds of Potentialities
Up: 7. Potentiality
Previous: 7.1 Change as Actualising
Prof Ian Thompson
20030225
