[John Gabriel to Tom Bourbon 921216 11:54 CST]
From Tom Bourbon (921216 09:18 CST)
Re: Citations of PCT; Social literature; John Gabriel
If anyone has citations for applications of PCT, in any setting, I
want them. Keep my address on file and send or post anything you
find. I will be grateful.
For one specific application, Clark McPhail, one of his graduate
students, and I are looking for citations of PCT, and any of the
half-baked derivatives of PCT, in the literature on the behavior of
people in crowds, gatherings or small groups. We also need
citations of work in which authors claim that in crowds people lose
their minds, come under control of a group mind, lose "the ability
to self-monitor," become "deindividuated," and so on. You probably
get the picture. Please send anything you can.
Even more specifically on the topic of citations, this is to follow
up on a post that might have been overlooked:
Tom Bourbon (921215 00:48)
[gabriel to powers 921214 11:35 CST]
Subject: PCT and war
Actually, this is a request for information. The following remark
occurred during your musings in "PCT and war:"
How do you learn to spot those small mistakes soon enough without
millennia of Darwin backing you up? Increasingly critical problem
when communication works faster, and those who have been applying
PCT in advertising agencies have a substantial hand in deciding
who gets to be president and C in C. Perhaps it was better when
it took three months to go from Oregon to Washington to kick butt
of elected rep.
"... those who have been applying PCT in advertising agencies have
a substantial hand in deciding who gets to be president and C in
C."
I collect citations of PCT and I am always looking for new areas
in which PCT is applied. I have not seen, perhaps because I never
looked for them, applications of PCT in advertising. I would like
to add that specimen to my collection. Can you provide a few
specific citations and examples?
I am serious. I will appreciate any citations you can provide on
people in advertising agencies who use PCT to sell products and to
influence presidential elections in the United States. My
collection of applications will be incomplete without citations for
applications as important as those. Don't keep them for yourself!
Well, not the firestorm I half expected, but the seemingly innocuous
request for citations. CAPIVI. I am speared. BUT
There's a difference between
doing PCT in detail, with all the hierarchy, about which I have some
fairly serious doubts because there's so much ECSs seem to me unable
to accomplish without interactions so extensive that the interactions
become more important than the ECS's, and Bill's wonderful insight
with which I completely agree, that people or any other organism,
or even state machine, do things because of their perceptions,
(for state machines, read inputs) or sometimes to change their
perceptions. Carelessly put - In order to change some of their
perceptions is the way the previous thought should have been
stated.
If you want a PCT based statement of policy for an advertisng agency,
I don't have it, and don't plan to waste time looking for it.
If you deny that one of the purposes of advertising is to change
perceptions of products, political candidates, or other things,
so that the behaviour of those viewing the advertising is changed,
I think you are very likely wrong, and I believe others will agree
with me.
Now, I'm not saying the hierarchy is nonsense, it isn't, but I only
believe it somewhat more than I believe in the Id and Ego. It's one
of many at times useful approximations to the truth, which we do
not now know, and which it can be reasonably argued neither we,
nor our intellectual inheritors - I've phrased that carelessly,
but no matter - may ever know.
There does seem to me a very convincing explanation of puzzling
things in the reliability of people in doing jobs like picking
up glasses of water, or following randomly moving cursors. Following
the cursor has very clear reference signal - the cursor position,
and I have no trouble understanding it. Picking up the glass of water
I have some trouble tracing all the signals, but I think a cogent
case can be made that they have homomorphs somewhere in the neuro-
anatomy and I think a homomrorphic finite state automaton (a computer
and software) might very well be built to mimic the process of
scene understanding, and picking up the glass without spilling it.
I've been building feedback systems since 1941, and doing their
mathematics since 1946 - the little book by Carter published in the
UK on Heaviside's methods that my father and his colleagues used
to teach people who went on to build radars and gun turrets, so
I think I understand control and feedback quite well. I don't know
the literature of neuropsychology and human behaviour at all, and
have only a nodding aquaintance with the literature of animal
behaviour and population genetics, and some of those other things
that involve feedback mechanisms.
So, I don't know your world very well, and I apologise for treading
on toes when I do so. I do know a little about the state of the art
in UAVs - the 1 ton equivalent of picking up the glass of water, and
I know that the PCT hierarchy is not yet quite satisfactorily
implemented in that area, and I think that when SOMETHING is done
that really works, it will owe to Bill P. and all of you. I gratefully
acknowledge that debt. I think it will have some other important
things in it besides the current content of PCT. I'm glad and proud
to be in the group if I'm acceptable, I admire you all.
I'm disinclined to chop logic about detail that I think will be
replaced by other better insight.
Now let me say once again what I AM interested in because I may be
able to explain my mild irritation with total missionary zeal for PCT.
I think the following things are well founded, and unlikely to be
replaced except possibly in the sense that Einstein replaced Newton,
and I reemphasise that Newton is good enough for a lot of Govt. work
provided you stay outside the fence of Los Alamos - to make a terrible
pun.
1. The mathematical theory of linear feedback systems as put forth
for example by Bode - Network Analysis and Feedback Amplifier
Design 1945 Van Nostrand. If all the participants of CSGNET
had read and understood what Bode has to say, there would be
less confused argument about reference signals and dp. But it's
not fair or reasonable to ask that, any more than it's possible
for me to have read to any extent in psychology. There are
other books easier to read, and less adequate in dealing with
multiple feedback loops.
2. The idea of classical contact transformations, as first put forward
by W.R. Hamilton. The classical contact transformation is the
operator that takes system state from that at time T to that
at time T+dT. It is itself state dependent, but quite clearly
its eigenvalues and eigenvectors now tell you a very good
approximation to system state a moment from now, given the
present state. This idea becomes the idea of a semigroup for
systems having discrete states, and the symmetries of the
system are the group of operators commuting with the semigroup.
This path of investigation quickly becomes a mathematical
mountaineering feat, which is a pity, because I think it is the
proper theory of Gestalt, and perhaps some other things. It is
my ambition, one day, to "push these ideas to their limit" as
Avery Andrews has said. And if I do, I'll try to hew a more
accessible staircase to the peak.
3. The idea of the rate of information transmission down a discrete
channel, being the the upper bound of the number of binary
decisions a recipent can make in a second, and first put
forth by Claude Shannon in the two 1949 papers in BSTJ. These
are eminently readable for those who know high school algebra,
provided the discussion of continuous channels is left on one
side. This idea is very important, because "information" is
what travels along feedback paths, and "decisions" are
determinants of conscious behaviour. Thus, Shannon provides
framework much simpler than Bode, for discussion of very
general theories of control in the style of PCT. Although
Shannon does not discuss stability, I think stability
is only an important side issue as compared to information.
Certainy in Bill's book information in the form of
reference signals is central, stability is usually
assumed, in fact I am not sure the issues in positive
feedback systems as implementors of memory are even
discussed.
4. The ideas of conventional Decision Theory and Value Systems
are an adequate first approximation to human behaviour
in decision making to support qualitative analysis,
and if estimates can be made about values, quite good
quantitative analysis.
Thus, for very general rather abstract theories, still having
concrete numerical consequences once you understand the parameters,
itesm 2. 3. and 4. seem to me a sufficient foundation for discussion
of decision making in a wide variety of human activity. And Bill P's
obervation that you can only act on what you perceive goes to the
heart of matter. It is exactly why the light that Shannon sheds
on reliable perception is important.
Thus, decisions and behaviour in societies of one kind or
another, seem to me driven by information in exactly the sense
that Bill observes, when he says we can only act on what we perceive,
and on reliable information in the exact sense of the theories
of Shannon and Bayes, together with the kind of searches of
solution spaces performed in any one of a number of theoretical
frameworks, from resolution based theorem proving a la Herbrand, and
Wos, optimisation after the style of many people, e.g. M. J. D. Powell,
or J. More' and other more outre' approaches to the problem of
discovering new things.
I am very much interested in the problems of making wise decisions,
value systems and objective functions for searches and so on.
I think these things are a long way away from your interests, which
makes fertile ground for misunderstanding. And perhaps we don't
have the same ultimate objective after all. Very likely, as
in the problem of the Spanish Barber, we shall just have to follow
our ideas around and see.
Please forgive my legpulls on Bill P. He's old enough to stand
up for himself anyhow. Also I confess with some pride to interest
in things military, and a concern to keep casualties on both
sides of armed conflict to a minimum. If you decimate an enemy
his descendants will be your enemies for generations, as Tom Baines
points out. Thus to make Bill C's point once more I may be
concerned with things military, but I am not on the side of
slaughter or armed dictatorship. A Citizen Army is the fail
safe control system for Eric Linklater's description of
democracy - "A well shod electorate, and Govt. with a tender
backside."
Best
John Gabriel (gabriel@eid.anl.gov)