🚀 go-pugleaf

In article <a6UG02ww89FI01@amdahl.uts.amdahl.com> kp@amdahl.uts.amdahl.com (Ken
Presting) writes:
>
>I would deny that the interrelationship of semantics with more general
>cognitive features makes it either impossible or unproductive to define
>semantics in isolation from the rest of cognition.  I see the situation
>of semantics as similar to knowledge representation, motor control, or
>syntactic competence.  We should analyze them separately at first, then
>consider the interfaces, and proceed from there to a full system.  It's
>OK, of course, to work in parallel on all these, just don't rule out the
>serial approach.
>
Ken, I think you have put your finger on the heart of our disagreement;  and
while I try to be careful about getting too extreme with words like
"impossible" and "unproductive," it certainly WAS my intention to introduce
a cautionary remark about your approach.  Perhaps another way of putting it
is that, believe it or not, I, too, am trying to sort things out;  however,
we see different "things" as being fundamental.  Let me see if I can capture
the distinction in a manner upon which we can agree.

The impression I get is that your fundamental concern is with employing
appropriate forms of symbol systems as abstractions for natural systems.
Thus, you list systems such as semantics, knowledge representation, motor
control, and syntactic competence and advocate that abstractions for each
of these systems may be developed in relative isolation as long as one
recognizes the need for appropriate interfaces.  This is, essentialy,
a good, healthy, modular approach to software development.

The reason I am questioning what would appear, to most of our readers, to be
almost absolute motherhood actually stems from personal experiences in software
development.  One of the lessons I have learned is that the modular approach
generally works best if you already know what the modules are!  (I've always
felt this is the most important justification from Brooks' adage to "build one
to throw away."  Only after you've built the "first draft" do you begin to
develop a suitable intuition for what it is REALLY made out of.)  With regard
to the discussion at hand, I am prepared to argue that we are still so far from
implementing intelligent behavior that any attempt to approach it in terms of
modules (even modules which carry all the weight of tradition in logic,
linguistics, and philosophy) MAY (note that I shall not stick my neck out
with "will") mislead us.

Another way of putting all this is that, even if you think you have identified
a viable set of modules, you may still not be able to avoid a rather high
bandwidth of communication across your interfaces.  This means that the
progress you can make in studying any one module in isolation will be severely
limited.  (This is not to say "unproductive;"  but it will be productive to the
extent that you are aware of the limitations.)  In the case of language, we see
the extent of such complex interactions as early as Terry Winograd's pioneering
work.  One of the reasons he built his system on a procedural representation of
knowledge was to establish a better handle on all those interactions.

In conclusion, I do not think the issue is one of whether or not we take a
serial or parallel approach.  What is important is that, if we try to build
a model, we should try to build one large enough to accommodate some corpus
of intelligent behavior.  Part of the trick is defining such a corpus with
a scope small enough to admit of implementation but broad enough to be
interesting.  Chinese rooms are clearly beyond that scope level.  Rather
than wax philosophical about how they might turn out, we should look for
some form of behavior on a more manageable scale.  Then we can assess whether
or not such traditional "modules" as syntax and semantics are really as useful
in our studies as conventional wisdom would have us believe.

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USPS:	Stephen Smoliar
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