You say that critical realism is the epistemological background of Gestalt theory.
Could you please explicate what that means?
The critical realistic model of the perceptual world has fundamental significance.
This model postulates a distinction between the physical world (physical body and
physical environment) and the phenomenal world (phenomenal body ego and phenomenal
environment).
In the waking state, the physical world is represented - more or less accurately
- by sensory and memory processes in the brain. At this point one has to distinguish
between the phenomenal facts and the brain correlates. We are inclined to adopt
a view of psychophysical identity, isomorphism or parallelism. This is not a purely
philosophical question, rather, it is a matter of working hypotheses which can be
subjected to empirical testing and are not dependent on exact phenomenal/brain distinctions.
According to Gestalt theory, the complex sensory-motor feedback system of the
human physical organisms is to be conceived of as a servo-mechanism which serves
the finely-tuned, energy-saving control of the organism. The main control center
of this circuit system lies in the brain. There the physical world is represented
more or less exactly as the phenomenal world (phenomenal body ego and phenomenal
environment) by means of sensory processes. The control of the organism can be compared
to the control of a large airplane in whose cockpit all the relevant data about
the airplane and its surroundings are represented by the transfer of computer information.
In a dream, the sensory-motor feedback system is interrupted to such an extent that
both intended [output] and immediately experienced [input] body movements do not
lead to corresponding movements of the physical organism itself. The sitaution in
a dream is therefore comparable to the one of a pilot in a flight simulator.
We must empathically distinguish ourselves, however, from naiv-realistic conceptions
(e.g. GIBSON, 1979) and from the idealistic and similar radical constructivist conceptions.
The radical constructivists confuse the critical-phenomenal conception of the physical
world with the physical world itself. The former is constructed on the basis of
perception and thought, and frequently changes; whereas the latter obeys unchanging
natural laws. A naive-realistic model has, for example, especially negative consequences
with respect to research and practice in the field of lucid dreaming and the related
field of out-of-body experiences. It not only hampers research, but for people who
misinterpret such experiences it can have very dangerous consequences, possibly
leading to serious mental disorders.
Just as the perceived world can provide us with information about physical reality
despite the many deceptions and illusions, the dream world can present us with information
about our psychological reality (the psychological person and his or her psychological
situation), despite symbolic distortions. In general, we take the term "reality"
to mean simply anything that has an effect. Accordingly, we understand psychological
reality to mean the totality of that which can have an effect on our experience
and behavior (see LEWIN, 1936). This would especially include the so-called unconscious
facts which we can conceptualize as psychological constructs and which can basically
be replaced by physiological concepts at a later time.