The recent discussion regarding disturbances, triggered in part by my
"squinting" example, prompts me to ask some further questions. I'd also
like to attempt clarifying what Bruce Nevin said about separating the
disturbance from the source of the disturbance.
It seems to me there are two classes of disturbance: (1) those that we are
consciously aware of and attend to as such and (2) those that are simply
compensated for in our behavior with no thought to disturbance as such.
The second kind is represented by driving on a windy day. We don't give
much thought to the wind as a disturbance; we simply compensate for it in
our driving. Another example from my Navy days: I spent 14 years on sea
duty, some of it in rough weather. As I walked down the deck, whether going
forward or aft, the rolling and pitching of the ship I had to adjust my gait
so as to maintain my balance and forward movement. ("Sea legs" is the
common term and I developed the rolling gait of many a sailor.) It is only
with hindsight and knowledge of PCT that I conceptualize a disturbance in
that experience.
The first kind of disturbance, the kind we view as such and to which we give
deliberate thought as to the means of compensation, is perhaps represented
by a businessman's response to the successful launch of a new product by a
competitor. The businessman is controlling for factors such as sales and
profitability and things were going along just fine. But, the competitor's
new product takes away sales and profits and requires a response of some
kind so as to restore sales and profits.
Does what I've just said make any sense? Is there any value in
conceptualizing two classes of disturbance? Are the two examples I've given
any good?
Now, as to Bruce Nevin's distinction: Earlier, I used a sunlight example and
indicated that I had to squint (whether to continue driving safely or simply
to protect my eyes needn't detain us at this point). The sun, if I
understand Bruce Nevin's point, is the "source" of the disturbance. The
"disturbance" itself is the effect of the sun's rays on my retina. Do I
have that right?
Regards,
Fred Nickols
"Assistance at a Distance"
nickols@att.net
www.nickols.us