Control of perceptions; arm-waving

[From Bill Powers (950524.1730 MDT)]

Martin Taylor (950524 14:00) --

     The skilled hunter catches fish. I claim that in doing so he is
     controlling his perceptions. If I understood Rick's earlier
     comment on Hans' posting, Rick would say that if the hunter hits
     the fish with the spear, he is demonstrably NOT controlling his
     perceptions, but is instead controlling an outer-world variable.

He's not controlling the perception you're thinking of, but he's
controlling a perception nonetheless. The perception is "such-and-such
an angle relative to the direction of the fish." A hunter shooting at a
bird leads the bird by an angle that has to be perceptually judged, and
shoots at that angle instead of directly at the bird. Neither the fisher
nor the hunter is capable of aiming at where the fish "actually is" or
where the bird "is going to be." The controlled perception is an aiming
direction that is in a learned relationship to the perceived direction
of the target.

···

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Bruce Abbott (950524.1000 EST)
I must have missed a post, or maybe it hasn't come yet, but I get the
idea:

     Not necessarily, but I don't seem to have a fly/bee wiring diagram
     here in front of me at the moment, so it's a little hard to tell.
     Bees are able to keep the flight motor running while within the
     hive in order to provide hive "air conditioning," so for bees at
     least, there must be some means to override the "stop" signal
     ordinarily produced by footpad pressure. This would suggest that
     foot-pad pressure is only one input of a more complex input
     function. The inhibitory output signal that stops the flight motor
     probably appears when there is an error in any of several control
     systems.

When a bee takes off, the result is to remove foot-pad pressure; when it
lands, the result is to produce foot-pad pressure. Anything else you say
about it even with a so-called diagram of the nervous system in front of
you is just arm-waving. You can tell arm-waving when you see it: as soon
as a counterexample shows up, like the bee being able to operate its
wings while hanging on with its feet, another glib explanation is tacked
onto the argument: now we have to have an override to the supposed
"stop" signal, which probably didn't exist in the first place. And then,
I suppose, when the bee lets go with its feet and takes off to fly from
the hive, the "override" signal that has been countermanding the "stop"
signal has to be turned off by an "override repressor" signal -- which
has to be turned off by an override derepressor signal to allow the bee
to land somewhere else, and so on and so on and so on. This whole
approach to explaining behavior "neurologically" is a crock.

I think that all neurophysiologists ought to be required to take courses
in circuit design and construction, both analog and digital, before
they're allowed to open their mouths about what the nervous system
actually does.

I wish we could get off of this kick and get some modeling work done.
The world is full of people making wild guesses about how the nervous
system works, but it's all verbal and hardly worth paying attention to.
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Grumpily,

Bill P.