[From Bill Powers (931022.1500 MDT)]
Bruce Nevin (931022.1547) --
The only strong examples of category perceptions that I recall
being forwarded are those to which we refer with words.
Yes, we refer to them with words, but we refer to many other
perceptions with words -- for example we refer to a certain range
of color-perceptions with the word "green." But the word green is
not the perceived color-sensation.
We can also refer to them without naming them:"Would you hand me
the color chip that matches this?"
The same goes for categories. "I need something to pry with" is
an implicit request that can't be fulfilled unless you can
perceive items as being in that category. Unless you have already
perceived membership in that category, there's no way to know
whether the words apply to that item.
To me, the hallmark of a category perception is that when you
look at an example of the category, you see not that particular
example but a likeness to a general kind of thing. That is, you
see "Mississippi" and you perceive a rivery sort of thing. Or you
look at a stack of umbrellas and you see which one is "yours." Or
you see not "that big umbrella, that small umbrella, that broken
umbrella" but what you refer to as "umbrellas."
I suggest that the discreteness and referentiality that we
attribute to those category perceptions could actually
properties of the word perceptions.
What properties could a word perception have? If there is a
perceptual signal indicating that a word has occurred, what other
information could that same signal carry? How can a signal carry
out any kind of function?
I don't understand "referentiality." Do you mean some property of
being capable of referring to something else, with no outside
help? If a word "refers" to something, it's not the word doing
the referring, is it? The word is just a signal; it can't DO
things to other things. I can understand a process that uses a
word-signal to refer to (in place of) some other perception, but
the process is neither the signal nor the other perception: it is
something that performs the function of referring, whatever that
means.
If phonemes are categories, they are unlike other
(or many other?) categories in this exhaustiveness of a well
defined and familiar subdomain of perceptions.
I'm not willing to say that phonemes are categories. They're
perceptions, yes, but why at that level? The mere fact that
different sets of sensations can produce the same phoneme-signal
doesn't imply that category perception is involved. That's just
how all many-to-one perceptual functions work, whatever the kind
of perception. Any why assume that categories exhaustively define
a domain of perception? As far as I know, the number of possible
categories is unlimited and there is no need for them to be
mutually exclusive. A doughnut and three dimes can be one
category, and two dimes and two doughnuts another. If you have
some reason to make such categories.
Any perceptual signal exhausts the domain of values that that
perceptual signal can attain. Three perceptual signals combined
in three orthogonal ways exhaust the space defined by the three
signals. This is true of any perceptual function. There's nothing
unique to any one level there.
···
===================================
I don't deny that there are perceptions of the sort that we call
categories. I am only proposing that they are not located on a
category level.
> reference (r)
>
perception (p) V error (e)
---------->comparator-----------
> >
perceptual output ORGANISM
input (PIF) function
function |
> >
><---------IMAGINATION-----------|
> (copy of r) |
: :
: : [lower levels
omitted]
: :
: :
=======^================================V=====
> >
> > WORLD
<------------CEV<--------------- [multiple loops from
lowest ECSs]
^
> disturbance
>
In the first place, the arrow you have drawn is not a copy of r,
but of the output signal, which is a function of r - p (the error
signal), not r alone. The imagination connection is a copy of the
reference signal sent to a system at the level BELOW, acting like
the lower-level perceptual signal that would be generated if
control were perfect at the lower level. And this is only one
INPUT to the higher-level system, not the perceptual signal. For
total imagination, EACH reference signal sent to a lower system
would have to be routed back to the input function of the higher
system.
In the second place, in PCT nothing is perceived unless it is in
the form of a perceptual signal. The arrow crossing from output
to input is not a perceptual signal, but a pathway carrying
information to an input function that generates a perceptual
signal. The whole structure of the HPCT model is predicated on
the assumption that ONLY perceptual signals are experiencable. If
other signals were experiencable, there would be no need for the
imagination connection. You'd just perceive the output signal.
But then, of course, you'd need appropriate perceiving functions
for each possible source of experience. Also, you'd have arrows
running from every part of a control system to higher levels,
instead of just copies of the perceptual signal (which is
anatomically correct, as far as we know).
If a copy of r can be used in the imagination loop within this
ECS, then it can equally feasibly be used as a category
perception that categorizes all of the possible combinations of
lower-level signals into the PIF of this ECS such that p = r in
this ECS.
Your assumption that the imagination signal represents r as drawn
is incorrect; all the imagination signal represents is one of the
perceptions that a lower system would produce if it controlled
perfectly. But beyond that, YOU are recognizing that some signal
could be used to stand for a category, but where in the diagram
is the capability of having that recognition? You're standing off
to one side, using your own ability to recognize categories, but
you haven't said what it is about the diagrammed system that
would be capable of reporting "that is category X." In fact there
is nothing in the diagrammed system that can do that. You need a
perceptual function that is capable of taking in information and
emitting a signal indicating that a category is exemplified in
the information. I claim that you're USING such a perceptual
function, but it's not in the system you're pointing to. If all
perceptions are the outputs of perceptual functions, then
perception of categoriness of any kind is the output of a
perceptual function. If you don't think that's true, then you're
starting a new model from scratch.
I don't know how to get this across. I've actually had people
tell me essentially the same thing about every higher level in
the model. It all depended on where they liked to spend their
time being aware from. People who like to operate from the
principle/generalization level have told me that principles are
simply the basic laws of nature, not a level of perception.
People who like to be logical have told me that logic is just
inherent in the way things interact with each other. People who
like to study relationships assure me that they study
relationships, they don't make them up. Now you, who like to
categorize, are telling me that categories aren't a level of
perception. What am I supposed to say? What would you say if
someone said to you that colors aren't perceptions, they're
attributes of objects? If I start backing down here, I'll soon
have to admit that relationships, configurations, sensations,
events, principles, yahdahyahdahyahdah, are really there and
somehow we just sort of KNOW about them, without the aid of
perceptual functions to construct them. The whole thing would
collapse, wouldn't it?
--------------------------------------------------------------
Best,
Bill P.