[From Rick Marken (991222.1440)]
Martin Taylor (991222 14:37) --
What I'm trying to show is a major distinction between the
control of analogue variables and the control of categorical/logical
variables, a distinction well demonstrated by your spreadsheet.
Well, then we are interested in different things. There is certainly
a difference between categorical and analog variables but none that
seems to make an interesting difference in the context of my
Along with Bruce Gregory (991221.1741 EST) we can ask why it is that
trouble so seldom happens when we really do put constraints on people's
low-level reference values or on their external feedback loops (which
in control theory has much the same effect).
Because the constraints (internal goals) are not imposed. Most
people set these "constraint" goals (like the goal of following
traffic laws) for their own (higher level) reasons. And they
control for those goals only to the extent that doing so doesn't
interfere with their ability to achieve other goals. Few people
are so committed to following traffic laws that they would not
violate any one of these laws (such as the speed limit) in order
to achieve higher level goals (such as getting their injured
child to the emergency room quickly).
My problem with simple agreement is that although the spreadsheet
clearly shows that _some_ of the control the system had is lost,
it also shows that the probability this matters in any particular
case is very low, and therefore the relevance of this loss of control
to any real-world sitation may also be small.
The demo says nothing about the "probability this [loss of a
control system] matters in any particular case". It shows only
that fixing any reference at an arbitrary value leads to loss
of control. It says nothing about the probability that this loss
of control will "matter" (whatever that means) or not
given that we both acknowledge (and on my side have always
acknowledged) that there exist reference conditions at the third
level that cannot be met when a second-level reference is fixed,
do you agree that the difference is that you find it definitive
that such conditions exist, whereas I emphasise more the fact
that they are very rare in a big hierarchy?
Not quite. From your point of view, the demo shows that any
control problem created by "committing" to any arbitrarily selected
second level reference is _small_. From my point of view, the demo
shows that "committing" to any arbitrarily selected second level
reference makes it impossible for other control systems (higher
(4th) level or intrinsic systems) to use the level 3 systems to
achieve their perceptual goals. Whether or not this is a "small"
matter is something that can only be determined by the
hierarchical control system that has been deprived of this
Your point of view is that forced commitment to a goal isn't
necessarily a big deal. My point of view is that your point of
view is 1) wrong (you have no idea, in any particular case,
whether the loss of control that results from forced commitment
to a goal will be a big deal or not) 2) disrespectful (because
it assumes that you _do_ know that the loss of control will
be no big deal to the system) and 3) misleading (because it
makes PCT seem complicitous in your advocacy of the judicious
use of coercion -- such as that which is involved in getting
a child to make a commitment).