[From Rupert Young (2017.12.29 17.15)]
(Rick Marken (2017.12.25.1930)]
Here the terminology seems a bit problematic. By "external variable"
do you mean a perception, which is of something that appears
to be external, to the perceiver? Some may appear to be
internal and some may appear to be external. But, at the end
of the day it is a (internal) perception which is being controlled?
If so, then I think we need to change the terminology; how about
“apparently external variable”? Btw, here you describe “principle”
as “internal”, but later in the post you list it as an “external”
variable.
I am trying to get to grips to what is the heart of any
disagreement, if there is any. I think it is just a terminology
issue.
(Marken (2017.12.20.1830)]
RM: But it seems unlikely since Boris (and and just about everyone
else on CSGNet) seems to think that it’s only perception that is
controlled and that variable aspects of the environment are only
controlled as a side effect of controlling perception.
You seemed to express the disagreement above, but, if you are saying
that “aspects of the environment” are synonymous with perceptual
variable with “apparently external variable” and with perception,
then I don’t think anyone on here would disagree. Yet you seem to be
making a distinction between perception and “aspects of the
environment”.
Ok, so we could say that functions "exist" in an abstract sense. But
would you not agree that we can’t control if the function itself is
abstract? For control to happen there has to be a physical function
in existence, that is actually performing the “computation”. So, in
order to reconcile different perspectives, could we say that
perceptions are the physical realisation of “aspects of the
environment”? Therefore, there is no contradiction is saying that
only perception is controlled and “aspects of the environment” are
controlled.
As you say an "external variable" could correspond to an
environmental variable. I think the issue has been that people have
taken “aspects of the environment” to mean environmental variables.
So, in the example of turning the dial to control temperature in the
shower, we only control our perception of the temperature
(perceptual variable/aspect of the environment), and not the actual
temperature, the environmental variable. However, as the
environmental variable could be seen to increase to particular value
and maintain that value, in the face of disturbances, it is said to
“stabilize”, or be indirectly controlled (the environmental variable
and the perceptual variable are physically linked through the
perceptual function). Does this fit with your perspective?
Regards,
Rupert
···
Rupert Young (2017.12.23 17.55)–
RM: Hope that’s all perfectly clear!
RY: Broadly, yes. Though Ithink there is still some terminology that needs
some clarification. For the moment can we forget
about the observer, to simplify things by removing
some variables from the discussion, such as q.i.
RM: OK, I’ll give it a try.
RY: What external variablesare stabilised?
RM: Depends on what you mean by "externalvariables". See below. Since I take “external
variables” to be synonymous with “aspects of the
environment” then vertical optical velocity,
d(arctan(z/(x-fx)/dt and horizontal displacement,
arctan (y-fy)/(x-fx) are external variables that
are not only stabilized, they are controlled.
RY: So, here is a bit ofconfusion for me as you appear to be using “external”
in two different ways (perceptual variables are not
external to the fielder, yet are “external
variables”). Would you clarify?
RM: Bill used the term "external variable" or
“variables external to the controller” to describe
perceptual variables that are experienced as
being “out there”. When a fly ball is hit towards you, you
can see its vertical and horizontal movement as being “out
there” where the ball is. Higher level perceptions, like
the perception of the degree to which someone is carrying
out the principle of being honest in his dealings with the
electorate, for example, seem more “internal”, like
cognitions. But both “external” and “internal” perceptions
are perceptual aspects of the physical environment –
environmental variables.
RY: Perhaps, then, the terminology of "aspects ofthe environment" is only relevant if we are
including the “observer” in the discussion?
RM: I don't think so. "Aspects of the environment"
describe possible functions of environment
variables – the later being the variables of physics and
chemistry that we believe to be what is actually out
there. These functions exist whether anyone is
actually computing them or not. Area is an example; it is
a function of environmental variables that it is possible
to compute, whether anyone – observer or controller – is
computing it or not.
RY: Are environmental variables thesame as external variables (if we are omitting the
observer from the discussion)? If so, would it be
correct to say that, in this case, no external
variables are controlled?
RM: I try to limit the term "environmental variable" or
“environment” to the physical variables that are thought
to be what s actually “out there” while I try to use
“external variable” to refer only to functions of
environmental variables that seem, when experienced, to be
external to the perceiver. What Bill (and I) call an
“external variable” could correspond to an environmental
variable. For example, I think the “intensity” perception
of weight is pretty directly proportional to a force
vector created by gravitational acceleration. But once
you get above intensity perceptions, I think we are
dealing with external variables in the sense of functions
of physical variables that, when computer by our
perceptual functions, are experienced as being external to
us.