[Hans Blom, 931110]
(Bill Powers (931109.0830 MST))
I have to clear up some misunderstandings quickly, before they start to
lead their own lifes.
Control is achieved
by an organism that has no knowledge of objective effects in the
external world.
I claim no such thing. I claim that you are a different person from me and
that the difference between us cannot be reduced to a different quality of
our receptors or actuators. I claim that the differences between us must
also depend on "tuning" of internal systems that is based on our differing
experiences, is somehow stored in our memories -- conscious or not -- and
is available in the processing that goes on between perceptions and motor
output.
Also, apes do it the ape way, humans the human way, although sensors and
effectors are very, very similar.
Walking in the dark is very different
from walking with the lights on. One walks more slowly, feeling
about with the hands, searching for an identifiable glimmer of
light. When no light exists, the mode of control changes
entirely; one controls for feel, not sight. If even feel is
missing, one doesn't control at all. At best, one can take some
steps under kinesthetic control.
Please define kinesthetic control of walking in the dark in terms of
feedback processes only.
We don't just stride on ahead when the lights go out.
We go into a drastically different mode of behavior.
Your remarks are demonstrably false. Everyone can do the following easy
experiment. Take a walk on a dark night in a predictable environment where
the road is even (no kinesthetic feedback) and there is no noise (no audi-
tory feedback). A typical lonely countryroad without a lining of trees
(which would reflect the sounds of your steps) will do. Walk at a brisk,
steady pace. Then let your eyes go into a "reverse blink" pattern; that
is, close them for about one second, then open them for a very, very brief
period of time. I predict that you will feel no need to slow down. Now
extend the period between "reverse blinks" to 2, 3, 4, then to 5 seconds.
Now you might feel a slight inner urge to slow down a bit. See how far you
can extend the periods between "reverse blinks". You will be surprised. No
slowing down, no groping, no searching for glimmers of light. The mode of
control changes not a bit.
Let's
remember that we're trying to explain what actually happens, not
change what happens to make it fit the concept of feedforward.
... or feedback. No bias, please.
Greetings,
Hans