# repairing lawnmowers

**URL:** http://discourse.iapct.org/t/repairing-lawnmowers/14818
**Category:** CSG1993
**Created:** [September 25, 1993, 3:14pm UTC](http://discourse.iapct.org/t/repairing-lawnmowers/14818 "1993-09-25T15:14:35Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![William\_T\_Powers2](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/w/c67d28/32.png) [@William\_T\_Powers2](http://discourse.iapct.org/u/William_T_Powers2)
#### Post date: [September 25, 1993, 3:14pm UTC](http://discourse.iapct.org/t/repairing-lawnmowers/14818/1 "1993-09-25T15:14:35Z")

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[From Bill Powers (930925.0800 MDT)]

RE: visit to U of Illinois in late '70s. I awoke this morning  
remembering that some time around then I gave a seminar at the  
psych department, I think sponsored by Brad Keeney (?). I don't  
specifically remember meeting Chris Wickens there, but in that  
context the name resonates. They didn't hire me.

Avery Andrews (930925.1215) --

Your example of fixing the lawnmower brings up a lot of  
fascinating problems. One of them is the answer to the question,  
"Why did I take the top off the lawnmower?" The answer could not  
have been "to grasp the frayed end of the cord and stuff it  
through the hole," because you couldn't see either where the end  
of the cord was, or that it was frayed, or what "stuffing" would  
entail. Before the top is off, all you have is an imagined model  
of what might be under the cover (assuming you've never done it  
or seen it done before). This model tells you that if you try to  
reach the cord without taking the top off, the top will get in  
the way. You don't need to try this in actuality -- reach for the  
imagined position of the cord and try to grasp it. You can see  
directly, in imagination, that your model won't work that way. So  
you can see that the top must be removed.

Then your model tells you that the top is held on in some way (if  
the casing is all in one piece you'd have to hacksaw it off,  
which doesn't seem a reasonable requirement -- how, you wonder,  
would they have assembled the thing?). Anyway, this leads you to  
look for something to unfasten. A bolt head or slotted screw head  
would fill the bill. So you search for something in that  
category.

You can't actually see the part of the bolt or screw that is  
under the cover, but you can imagine it. Your model includes the  
properties of bolts and screws, namely the fact that twisting is  
involved; also your model contains the correct direction of twist  
for unfastening. So you find the unfastening tool and use it, and  
remove the cover.

Now this really gets interesting. Removing the cover unveils a  
new world of things you've never seen before. The first job,  
before you can even try to do anything, is to make sense of it.  
This means getting everything you see categorized. There's the  
"pulley". That must be the "cord" wrapped around it. And that  
fuzzy-looking thing, alas, must be the "end of the cord." Looking  
at the inside of the cover, which you have never seen before, you  
search for something that is the "hole" as seen from the inside  
-- the same "hole" that you see from the outside.

Having identified everything in terms of the category to which it  
belongs, you can now proceed in several ways.

You could refer to a gigantic knowledge base in which words like  
"hole" and "end of cord" and "stuff" occur, and search for  
sentences describing operations that contain these elements,  
until you find a set of sentences like "pick up the end of the  
cord and stuff it through the hole." Then you would search for  
nonverbal actions that would be correctly represented by this  
sentence, turn them into reference signals for specific actions,  
and execute.

Or, you could simply imagine sequences of things happening, like  
your fingers holding the end of the cord, pulling it toward the  
hole, and pushing it through the opening. This method would have  
the advantage of being cast directly in terms of the relevant  
reference signals; the images being generated would serve without  
translation as reference signals.

In fact, I think the second method has to be used even when you  
elect to use the knowledge base approach. Right from the start,  
there has to be some imagined condition that you wish to create:  
the cord is threaded through the hole, and the handle is  
reattached. If you haven't already gone through creating this  
imagined condition, how will you recognize the sentence that will  
achieve it, as opposed, say, to the sentence "The cord is lying  
in a tangle around the pulley"? The \_very first\_ thing you must  
do is imagine the perceptual state of affairs that will  
constitute a solution to the general problem of repairing the  
lawnmower.

> **···**
>
> -------------------------------  
> Another fascinating thing that your example brings up is the role  
> of reorganization. Clearly, reorganization is always on tap,  
> ready to be used. Equally clearly, it is brought to bear on  
> precisely the control problem that is in consciousness. This  
> seems to support the idea that reorganization follows awareness.  
> When you're trying to imagine an action that will correct an  
> error, you're reorganizing. When you're trying to recognize the  
> elements of an unfamiliar part of the world, you're reorganizing.  
> You look at the bunched-up cord stuck in the hole, and think "I  
> want a smooth cord going right through the hole." How to make it  
> smooth? Reorganize, reorganize, reorganize ... and finally you  
> imagine it wrapped in something that will keep it smooth. What  
> kind of something? Glue? Glue dripping into motor, me sitting  
> around waiting for it to dry. Thread? Tedious wrapping, knot  
> coming loose, weak thread, can't find thread. Scotch tape? Ah,  
> Scotch tape works fine (in imagination), it's in the kitchen  
> drawer, it sticks to itself. Do it. While we describe all this in  
> words, the actual imaginings are in images. \_Image\_-ination.  
> ----------------------------------------------------------------  
> I'm on this tack because of having been reading BBS -- Mary  
> subscribed to it. I'm amazed at how some people try to make words  
> and symbolic operations accomplish everything. I don't doubt that  
> symbolic operations are used, but there are many control  
> problems, even some rather complex ones, that can be solved  
> without them. It seems to me that the "program" level would  
> operate in terms of pure symbols without meanings, and purely  
> logical or at least rule-driven operations. When you start with a  
> word-problem like "A farmer has a silo 17 feet in inside diameter  
> and wishes to store 110,000 bushels of corn in it ...", the first  
> thing you do at the program level is to convert it to a symbolic  
> program in which it doesn't matter what the specific symbols  
> mean. When you apply the formula for the area of a circle, you  
> don't care whose circle it is, or what color it is, or whether it  
> represents the shape of an object or of a hole. You just go  
> through the routine of applying the rule A = pi \* r \* r and  
> coming up with a number for A. At this level, it doesn't matter  
> what problem you're trying to solve by evaluating this  
> expression. The program (or maybe sequence, here) level doesn't  
> have to know any of the lower-level details, nor could it  
> perceive them even if given them.
> 
> When you repair the lawnmower, you achieve the goal using the  
> levels of control that are actually required. You don't use  
> sequence control unless sequence matters, and you don't use  
> symbol-processing unless the particular skills involved in  
> program-like symbol manipulation are required. You would probably  
> use the program level if the problem were to figure out how to  
> execute the steps involved in repair with the least expenditure  
> of energy or the lowest cost or the greatest chance of impressing  
> your wife with your dedication to household labors. Program-type  
> thinking is good for achieving program-like goals; it isn't  
> needed for anything else.
> 
> Sorry to free-associate like this, but it was a provocative  
> example.  
> -------------------------------------------------------------  
> Best,
> 
> Bill P.