I am resolved to work my way through B:CP for a second time.
The first time was in 1975 and I didn't exactly work my way
through it back then.
I propose to go through B:CP a chapter at a time, answering
the leading questions at the end of each chapter. Y'all can
comment if you like or simply ignore my postings.
Here goes with Chapter 1.
1. A man exercising raises a dumbbell slowly at arm's length.
In what direction do his muscle forces act on the dumbbell?
(Upward) Now he begins slowly to lower the dumbbell. In what
direction do his muscles forces now act on the dumbbell?
His muscle forces still act in an upward direction; however,
with less force.
2. A woman is pulling a reluctant little boy by the hand
toward a schoolroom door. In what direction do the boy's
walking movements carry his body? (Forward) In what
direction would the leg-muscle forces end to move the boy's
body? Do movements depend only on muscle forces?
The leg-muscle forces would tend to move the boy's body
backward. Movements can be effected (and affected) by
forces other than muscle forces. The rolling, pitching
deck of a ship at sea comes immediately to mind (but then
I spent 20 years in the Navy--on destroyers--so that's to
be expected). On a side note, I wouldn't refer to the
boy's "walking movements" as such; the imagine conjured
up in my mind is of a boy being dragged. What you call
his "walking movements" I would refer to as his "balancing
movements" (i.e., some mix of pulling back and trying to
remain upright--or at least not fall).
3. A man stands before a large screen tracking a moving
spot of light by keeping his finger on it. The effective
stimulus is the distance of the spot from the finger. The
response to a given stimulus is expressible as the position
and velocity of the finger relative to the spot. Is the
stimulus measure independent of the response measure? Is
any independent measure possible? Is there any response
that does not entail a change in the stimulus?
I don't know what "independent" means in this context so
I'll have to answer the questions as best I can.
Given that the stimulus has been defined as the distance
between the spot and the finger, and the response has been
defined as the position and velocity of the finger relative
to the spot, it seems to me that to measure the distance
between the spot and the finger you must know also the
position of the finger to determine the distance between
the two. However, you need only to know their positions
relative to one another and not in relation to any other
reference point.
The "kicker" in this is that the response includes the
velocity of the finger (which I take as referring to the
speed with which it is moving--again, relative to the spot).
This would imply that the velocity of the finger in relation
to the spot is the net of any speed of movement in the spot,
so again, you can't get at one without getting at the other.
As for independent measures, I imagine I could measure the
speed and direction of finger movement with respect to the
corner of the screen on which the spot is moving and that
would be independent of what the spot is doing but I don't
know that that would tell me much. Ditto for the movement
of the spot itself.
The only response I can think of that doesn't require a change
in the stimulus is if the spot were to remain stationary. The
finger would remain on top of the spot and neither would move.
The reference condition, that is, the condition requiring no
action, would be realized.
4. Behaviorists say that in apparent goal-seeking behavior,
the goal is reached because stimuli at each stage of the process
evoke the next response leading toward the goal. If a man is
operating remote guidance controls to steer a car through a maze
toward a goal, what will his response be if the car spontaneously
moves along the correct path at all times? What would happen if
the man did produce any steering movements?
Presumably, if the man noticed the car was doing what was wanted,
without (or despite) any effort on his part, he would "back off"
and let the car run the course on its own. If he did attempt to
steer the car, his actions--by way of the remote control device--
would constitute "disturbances" (which the car could presumably
counter because it apparently has a built-in control system all
its own).
As a side note, I find the situation in this last question really
interesting. I wonder how long it would take the man to realize
that all he was doing was "disturbing" the fine job the car was
doing on its own. (I wonder, also, what would happen if manager
was substituted for man and employee for toy car. Hmm.)
Anyway, there are my answers to the Leading Questions at the end
of Chapter 1 in B:CP.
Anyone care to respond?
···
--
Regards,
Fred Nickols
Distance Consulting
http://home.att.net/~nickols/distance.htm
nickols@worldnet.att.net
(609) 490-0095
).