[From Rick Marken (930828.1600)]
Michael Fehling (27 Aug 1993 18:01:36) --
In PCT, the word "perception" refers to the presense of a signal of some
amount in an afferent neuron. It is hypothesized that ALL experience is
perception. This includes what are called sensations, perceptions and
beliefs but it also includes desires, intentions and actions (to the
extent that these are experienced -- we can only experience desires,
intentions and actions as perceptions). Everthing we can talk about is
perception because all we experience is afferent neural signals. Talking
itself is a perception; the meaning of the talk is perception; PCT is
perception; physics is perception, feelings are perceptions, it's ALL
perception (at least according to PCT). Some perceptions are caused by
events in the environment outside the nervous system (including the
"internal" environment of the body -- muscles and organs). These are
the "common" perceptions -- what you experience as waking reality.
Other perceptions are based on events originating deeper inside the
nervous system itself. These perceptions are called "imaginations".
Imaginations differ from perceptions ONLY in terms of what causes them
(external events in the case of perceptions, internal nervous system
events in the case of imaginations); both are physically EXACTLY
the same -- they are signals in afferent neurons. Imaginations include
much of what you call belief (like the belief that my dead grandmother
isn't really standing here or the belief that there are perceptions
and beliefs); imaginations are also called thoughts (which can include
thoughts about how to model human behavior and about why one might even
want to do it anyway).
I think this is basically what Bill P. meant when he said "Beliefs,
as I see the term used, are _primarily_ perceptions". The "primarily"
part has to do with the fact that, when people talk about their beliefs
(imaginations) they imply preferred states for them (perceptions and
imaginations are variables). If you see your late grandmother before
you (p) and you believe (imagine) that she is not there you are preferring
to imagine "p is not true" rather than "p is true"; there are two
possible values of this logical belief and you prefer to have this belief
at one (rather than the other) of those values. So PCT has no trouble handling
the fact (I imagine it's a fact -- I've never experienced it; well, now
that I think of it, I have experienced it -- at magic shows; I perceive
one steel ring passing through another (p) but I believe that that's not
what is actually happening) that people can believe that they are not
perceiving what they are percieving; it also explains why they might
want to have this belief at one level (grandma's not really there)
rather than another (grandma is there); the reference level for this
belief (perception) would be set in order to satisfy higher order
references for perceptions of one's rationality or sanity, for example.
Your test of PCT as "designed to disprove [PCT's] claim..." sounds like the
Popperian view of science. I'll pass on this, but Kuhn, Feyerabend, Lakatos,
and others have challenged this approach to science in interesting and
influential ways.
"The test" that Bill described is NOT a test of PCT; it is a test to
determine whether you are actually dealing with the phenomenon of
control. Many phenomena resemble control -- things like the behavior
of a mass on a spring, a raindrop moving to the sea, a marble coming to
rest at the bottom of a bowl, an organization remaining headquartered
in the same town, etc. I think it is important to know the nature of
the phenomenon you are dealing with before you start trying to model it.
It would be a big mistake (I think) to start applying a control model
to, say, planetary motion before you have good reason to believe that
the planets are control systems (we already have a lot of evidence
that they are not).
Finally, I guess we may just have to agree to disagree about a theory/model
as a representation of "reality" versus a model as a view of reality.
This might turn out to be a very important disagreement. PCT (like
Newton's laws) purports to be a model of the unseen variables and the
functional relations between them that result in what we do see (in
the case of PCT, what we see is purposeful behavior -- control). If
a model is just a way of "viewing" reality then how do we test which
"view" is better? I prefer to evaluate behavioral models by comparing
their performance to that of real organisms. If you agree that that's
an acceptable way to evaluate models then we have no problems; you can
call a model a "view" of reality; we'll call it a representation of
the reality that underlies our "view".
Best
Rick