[From Bill Powers (951120.1500 MST)]
Martin Taylor 951120 14:10 --
(1) How can the cat-scientist determine that the appropriate
controlled perception is that of the stick moving?
The cat-scientist does not need to determine this. All it needs to
determine is that when it controls a certain perception p, the door
opens. The causal linkages between controlling p to a certain level and
the opening of the door do not need to be perceived. All that matters is
that when the cat controls p, a reliable side-effect (of which the cat
need perceive nothing) of controlling p is that the stick gets moved.
(2) How can the god-experimenter determine what perceptions the cat
is controlling when (by hypothesis) the cat is continnually
reorganizing until a side effect of some perceptual control results
in the stick being moved?
Presumably, when the perceptual control is found that will reliably move
the stick, so that reorganization ceases, the cat will continue to
control that variable, whatever it is, in the same way. The experimenter
can then determine what that variable is in the usual way. I don't see
the problem.
And now the new question (3) How can the experimenter determine
whether the cat is controlling any kind of perception of the stick,
or whether the success of the Test is a consequence of the
environmental constraints?
This choice isn't clearly stated. If the cat is just blundering around
in the cage until it happens to hit the stick, the experimenter would
quickly conclude that it is still reorganizing. If the behavior settles
down to some stereotyped control process, the experimenter can look at
the connection between what the cat is controlling and the motions of
the stick, and gradually alter the situation until the cat resists what
the experimenter does. Again, I don't see where there's any difficulty.
I'm not sure what you envisage, but I'm assuming that the
experimenter does two things while observing the cat. (1) When the
cat minimally brushes the stick, the experimenter pushes the stick
against the cat, and (2) at the same time the experimenter opens
the door.
No, that would put the experimenter into the loop. All the experimenter
does is to move the pivot of the stick (between trials) so the cat has
to exert more pressure against it in order to get into its stereotyped
position, or what we took for a stereotyped position. If the cat is
really controlling pressure against the stick, it will stop moving as
soon as the pressure reaches the previous amount, and the cat will never
get to the previous stereotyped position. If the cat insists on getting
into the previous position despite the change in pressure, then it's
controlling for position, not pressure.
If this is the right interpretation, would it not be the case that
the cat's reorganization would stop at the "brush the stick
lightly" state? Indeed, the cat may not be reorganizing at this
point, if it has already learned to escape by the stereotyped
procedure, so that the change of conditions would not be expected
to affect the stereotyped behaviour if the previous requirements
for "stick pressure" were later to be reinstituted by the
experimenter.
Once reorganization has ceased, I would expect the cat to continue
controlling whatever variable it was controlling. The only question is
which aspect of the outcome that we see at this point is the controlled
variable. It could be the sensed pressure against the stick, or it could
be the final position which just happens to entail pressure against the
stick as a side-effect. We can tell which is the case using the Test, if
we systematically disturb one proposed variable without disturbing
others.
This would be easier to see if we put a short delay between movement
of the stick and the falling open of the door.
I think I must be missing either the point or the description.
Suppose a human person rather than a cat person were thge subject
of this experiment. And suppose the human person had correctly
deduced that moving the stick was the key to getting out of the
box. If the stick pressure were to be increased, wouldn't the
human person push harder, to achieve the desired movement of the
stick, and yet harder if the door opening were to be delayed?
Deduction has nothing to do with it. How can you "deduce" the effect of
an action when you can't see any physical connection between the action
and the remote result of it?
You mistook my proposal to mean that the experimenter increased the
pressure of the stick against the cat. That was not the strategy; my
imagined experimenter moved the pivot of the stick between trials so
that if the cat insisted on putting itself in the same final position as
before, it would necessarily have to increase its pressure against the
stick in order to get there. If it did so, we could immediately conclude
that the cat was NOT controlling a perception of pressure against the
stick, and that it MIGHT be controlling for a specific final position.
Note that this experiment was done in such a way that control of the
door's opening would be successful in either case, so reorganization
would not be started up again. The Test always has to be done in such a
way that control continues to be successful. If your disturbances
prevent control from succeeding, reorganization may begin, in which case
you won't be observing the same system any more.
This goes back to very early discussions in which you assumed applying a
sudden disturbance that caused the controlled variable to change by a
large amount away from its reference level. I tried to convince you that
we have to define a separate disturbing variable with a non-exclusive
effect on the controlled variable, so that in principle the control
system could prevent any significant change in the controlled variable.
Applying a large disturbance does not mean that the controlled variable
will be significantly disturbed. We do not measure disturbances as
changes in the controlled variable, but as changes in a disturbing
variable, with the amount of effect on the controlled variable depending
on how rapidly and strongly the system opposes the effect. The
disturbing variable is an independent variable; the controlled variable
is a dependent variable, and it depends both on the disturbing variable
and on the output variable of the control system.
Imagine, for example, that the cat could escape by walking onto a
particular floor switch, or by rubbing on the wall away from the
stick, as well as by moving the stick. The different means could
be designed so that frantic cats might be about as quick to hit one
as another, by chance. When one method is used to escape, change
it slightly, so that the same stereotyped actions will not work.
See if the cat uses the same method anyway, because if it escaped
by side-effect, the other methods should be as likely to be used.
Keep doing this, disturbing whatever escape method was used last
time.
Your method uses disturbances that prevent escape from the cage, and
requires reorganization to find another method. The first time the cat
is in the cage after you have made such a change, it will control the
same variable as before. It will continue to do this until failure to
get the door open leads to reorganization; then it will find some other
perception to control that will open the door, and settle into another
stereotyped behavior. If your way of applying the test results in
failure of control, you will be looking not at one control system but a
whole series of control systems of different organization, and will
learn nothing about any one of them.
How do you know that what you think you have found out about the
way the universe works is right, and that you haven't simply found
something that correlates with an environmental constraint?
You don't. This is because the actual environmental constraints _never_
become visible.
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[Taylor replying to Rick Marken]
I don't know whether this is still understood to be the case, but a
few years ago it used to be said that people who tried heroin for
"recreational" reasons usually became addicted, whereas people who
were given it for medicinal reasons did not.
Morphine is still likely to produce addiction if it is "given" (to a
patient by somebody else) for pain. In modern hospitals, patients are
given control of the delivery of intravenous morphine doses, using a
button they can press whenever they want more relief from pain. The
effect is a dramatic REDUCTION in morphine usage. Mary has experienced
this method, and has never had the slightest desire for morphine outside
that setting, unless she goes somewhere else to shoot up.
If true, this suggests that it is indeed not the drug that "causes"
addiction, but a combination of the drug and the reasons for taking
it in the first place--falsifying, as you point out, the idea that:
one shot of a drug leads to addiction...
This sounds reasonable.
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Best,
Bill P.