[From Bill Powes (971109.0639 MST)]
i.kurtzer (971108) (replying to Rick Marken)
You seem to have been put off by the notion that an aspect of
ourselves is like an Observer (a "subject") for which another
aspect of ourselves (the hierarchy of control) is an "object"
of awareness.
rick, if you try to commmit your science (hierarchical control) to
philosophy
(Observer talk) then you will not be clarifying either but will bog both.
At
the least you are suggesing that you have solved the mind-body problem,
which
would then have to be explicated so you might tell me in just what way does
one "psychic shadow of self"- effort--have any connection to the (x*y) of
some
quadrilateral being controlled. This is a really screwy area. so
i suggest lets not committ one to other but see how truthful we make our
committments to either separately.
My problem as an engineer is that I have great difficulty with imagining
receiverless information. Everything we know about the nervous system says
that it contains perceptual systems which receive information, convert it
to new forms, and pass the result on as signals which are received by still
higher systems. Until something has resulted in the reception of a neural
signal by some function, it does not exist for the brain.
The "sum-and-difference" example illustrates what I mean. If there are two
perceptual signals, a and b, it is possible to perceive and control both
their sum and their difference at the same time. To do so for the sum
requires a perceptual function that receives both signals, adds them
together, and emits a signal proportional to their sum. Same for the
difference signal. The sum and the differences can't exist as separate
experiences until they have been perceived in this manner, even though you
could build a control system in which the comparator received both signals
and added them together with appropriate signs while comparing them with
the reference signal. My assumption is that all experiences must correspond
to explicit perceptual signals. If that weren't true, then we would
simultaneously experience ALL POSSIBLE functions of a and b, because all
possible functions are implicit in the two values.
Even given the explicit perceptual signals, we must still account for the
fact that they do not just participate in the creation of error signals and
hence actions, but are "observed" as experiences. The observer can't be a
higher-order perceptual system, because the perceptual signal at the higher
level doesn't represent any one lower-level signal; it's a function of many
of them, and it represents something that no lower-level signal could
represent. There is, in fact, nothing in the neural model that can _note
the presence_ of a neural signal, in the manner of a receiver responding to
an input.
So what IS "conscious experience?" Is it merely the existence of signals in
perceptual pathways? If so, it seems entirely unnecessary. And this
interpretation doesn't explain why experience seems confined, at one
moment, to a small subset of all the neural signals that exist in the brain
at a given time, or why it should be confined to _afferent_ neural signals
(as it is). And most important, it doesn't explain how the field of
experience can change from one time to another, so sometimes we attend to
one part of it, and sometimes to other parts at the expense of what was in
experience before. The variable content of consciousness is a big problem
for any proposal that would leave out Observation as a separate phenomenon.
Of all the aspects of the variable content of consciousness, the most
telling one is the fact that we can attend at different levels of
perception. We can attend selectively to intensity information or to system
concepts or anything between. But if the hierarchical control model is
correct, in order for any higher-level perception to be controlled,
perceptions at all lower levels must also be under control. This means that
when we are attending, say, to the route we will be riding on our bicycle,
we are still controlling perceptions of balance, effort, and so forth.
Those perceptual signals MUST STILL BE PRESENT and they must be under
active control -- yet they are not part of experience at that time. If this
were not so, the higher levels of control could not be working. If the
lower perceptual signals did not go right on existing as usual while we
attend to higher ones, we couldn't be riding the bicycle while we tried to
remember whether to turn right or left at the next corner.
What this demonstrates is that the existence of a perceptual signal is
independent of the experience of the perceptual signal. When I try to think
of a model that would have that characteristic, all I can come up with is
some sort of receiver that can be connected selectively and variably to
various afferent signals in the hierarchy. When this receiver is receiving
information from some set of perceptual signals, those signals are
consciously experienced. When it is receiving from elsewhere, those same
signals, even though they continue to exist, are not experienced.
It is very convenient, therefore, to have some evidence of the existence of
this selective receiver: it's me. _I_ can attend selectively to different
subsets of the perceptual signals that exist in my body. This is not the
"I" that is characterized by my physical or mental attributes, because I
can easily attend to something other than those -- the form of the Orion
Nebula in an eyepiece, for example, while forgetting that my fingers are
freezing. This "I" that is not any of those other "I's" is the receiver,
tuned into this or that aspect of perception, at high or low levels.
I, stripped of all other attributes, am the Observer. I am the one who has
experiences.
How do the arguments of the philosophers stack up against that analysis?
Best,
Bill P.