[From Fred Nickols (981018.1335)] --
Bruce Abbott (981017.1500 EST)
Fred Nichols...
To say that the output is "aimed" reads as though the output
is being produced by an entity with a reference condition for
the effect of the output on the original discrepancy. That's
got to confuse some people. I know it confuses me.Yes, although that _could_ be exactly the case. One may, after all,
intentionally do things in order to bring about some end -- even when the
end is correcting a disturbance to some variable. (Think hierarchically.)
Hmm. I think I understand your admonition to "think hierarchically"
and, in a way, I was. Lemme try again.
What I was driving at in relation to the C&S citation (reproduced
again below) is that attributing "aim" or purpose to the output in
a loop, introduces a new reference condition at an already specified
level of the hierarchy (i.e., whatever level the loop in question is
operating on). That's the source of my confusion, not that we are
controlling for many different things simultaneously and that, if
we're as complex as I think we are, a given output might serve more
than one level in the hierarchy.
Carver & Scheier (thanks to Marc Abrams)...
Pg. 503
..."What makes a feedback loop special is that the
proccesses in it permit self regulation. As indicated in the
main text, the loops _input function_ ( they italized it )
iis it's _perception_ of the way things are. The
_comparater_ checks this perception against a _reference
value_ , assessing whether the perception and reference
level are the same. If they're not the same , the result is
an _output_ ( or a change in output ). The output is aimed
at reducing the discrepency between perception and reference
value.
Bruce A...
However, my guess is that Carver and Scheier are speaking metaphorically, as
if the system had been designed with this purpose in mind. In that case,
"functions" might have been a better choice of term than "aimed." The
output _functions_ to reduce the discrepancy between perception and
reference.
Agreed; the use of "functions" (as a verb) or "serves" would not
have produced the confusion I experienced.
Regards,
Fred Nickols
Distance Consulting
http://home.att.net/~nickols/distance.htm
nickols@worldnet.att.net
(609) 490-0095