[From Bill Powers (951205.1015 MST)]
Martin Taylor (951205 11:40) --
Initially, when a person puts on prism spectacles, hand movements
are misdirected and may, as you point out, not be correctible in
the time of one attempted pick-up of an object. But after quite a
short time, things start to look more or less normal again, and
one's movements regain their external-world accuracy, more or less.
What do you mean by saying that things start to look more or less normal
again? As soon as the prism glasses are put on, you see a perfectly
normal world. There is no indication that it has been displaced until
you reach out for something. Then you find that the direction in which
you _see_ your hand extending is not the direction in which you _feel_
it extending. The kinesthetic spatial map is no longer aligned with the
visual spatial map.
The only interesting point about the chicks is that they seem unable to
realign the kinesthetic and visual spatial maps. The maps are apparently
permanently aligned when they hatch. Or at least, if they do have any
realignment capability, it does not have enough range to compensate for
the displacements induced by the prism glasses that were used.
As long as they don't do anything that will reveal this misalignment,
they can control perfectly normally, orienting toward targets, looking
at things by turning their heads, following moving objects (I would
guess), and so forth. Only when they try to make contact with an object
does the misalignment create a disturbance which (if they could do it)
would require correction.
As I remember, the only investigations carried out consisted of putting
carbon paper on the area where the chicks pecked and recording dots.
There would be clusters of dots to one side of the target seed. This is
a pretty sketchy experiment. We'd have to do it all over again (as
usual!) to get any data worth thinking about.
Chicks don't seem to learn, which suggests that the related control
system hierarchy is not easily reorganized, as compared to ours.
That's a pretty wild generalization from the limited evidence. The fact
that chickens (adult) can be operantly conditioned is a pretty good
indication that grown birds can learn. It's hard to imagine that the
adults can learn while the chicks can't. I don't doubt that there are
limits to what they can learn, set by the available types of neurons and
potential connection paths (no chicken, I predict, will ever learn
algebra), but let's not draw sweeping conclusions from practically
nonexistent data.
···
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CHUCK TUCKER 951205 --
I have a problem with Handy and Harwood's analysis of inquiry. It's so
general that practically anything you do by way of inquiry would fit
their terms. But given a problem, these general terms don't give you any
idea of what to do next. Consider the second step, right after noticing
that there is a problem:
He observes some facts that appear to be pertinent.
Various aspects and phases of the situation are
differentiated, some changes among them are measured,
and a tentative partial description of what is
happening is begun.
Come on, now, what is a "pertinent" fact? Obviously, it's whatever "he"
thinks is pertinent. Would anybody start looking for facts that are
_not_ pertinent? What are "various aspects and phases of a situation?"
Is there anything in the universe that wouldn't fit that description?
And "changes are measured," but what about magnitudes, or time
integrals, or relative directions in space, or rotational speeds, or
distances? Following this we get a "tentative partial description of
what is happening."
Sorry, Chuck, but this all sounds like pretentions blather to me.
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Best to all,
Bill P.