[From Shannon Williams (960101)]
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HAPPY NEW YEAR!
Bill Powers (951231.0930 MST)--
You can see that the black box converting sounds to letters isn't
necessary.
Yes. I realized as soon as I sent the post that I should have just
called it some kind of converter. The reason it was called a letter
converter was because Rosenberg and Sejnowski had been inputting letters
into the system. And up until five minutes before I sent my post, I also
was inputting letters into the system. At the last minute I decided to
speak to it instead.
The "pattern generator" should be a higher-level input function
(analyzer) that converts the basic perceptual signals into another set
of perceptual signals that represent invariants, just as the four
frequencies represented invariants of a phoneme.
We are not visualizing this "pattern generator" the same way. I
visualize something that changes its patterns every time that it is used.
The parts of the pattern that correctly generates an output which will
achieve control of the input should remain steady. But it will not be
invariant at all.
The "generated reference" is then just a set of recordings of
the signals from the input function that occurred together. When the
supervisor speaks a sound, the input function produces its perceptual
signals which are stored. Then the same reference signals can be
selected (by a higher-level system not shown), and the output function
(when designed) will convert the error into the sounds that will
reproduce the same perceptual signals, via the "speech synthesizer."
Would you draw a picture of this? I am not sure what you have in mind, but
you do not seem to mention anywhere how the "generated reference" evolves
over time. This reference *must* evolve. If it does not evolve then it
would mean that our perception of the physical world is not subject to our
goals. In other words, the sounds we hear as infants would sound the same
to us as adults. But the infant does not know which parts of sound have
meaning and which don't, so how can the infant and the adult have the same
reference for what perception is required?
-Shannon