LAB #1 - Mental Images: Drawing Out the Concept of Representation

(Developed by Andy Beedle and Dan Lloyd)

(Required Reading: "The Saga of the Modern Mind", pp. 15-46 in Haugeland's Artificial Intelligence: The Very Idea.)

Think of your high school math teacher. What makes that thought a thought of your math teacher? Could I have a thought of your math teacher? Would my thought and your thought be the same thought?

These seem like simple (or maybe stupid) questions, but it is disturbing to see just how difficult they are to answer. Obviously your thought of your high school math teacher is about your math teacher, but it's not identical with your math teacher. For a thought to be identical with your math teacher, it would have to have all of the properties that your math teacher has, like size and weight. A thought like that would be tough to get into your head (unless you had a very small math teacher). While it is possible that you and I could both have a thought of your math teacher, it is unlikely that your thought and my thought are closely similar. We each might think of different qualities of your math teacher -- I might keep in mind what a great golfer your teacher is, you might concentrate on what tough quizzes your teacher gave.

These considerations present us with two basic (and related) problems. The most difficult of these problems is what Haugeland calls the problem of "original meaning" (see pp. 27-8). Since you can't fit your math teacher in your head, how do you get a thought to be a symbol for your math teacher? What kinds of rules do you use to keep these mental symbols in order? How do you use them? In short, how do your individual thoughts take on meaning? The second problem is what I'll call "the translation problem". We can each think about your math teacher, but the qualities that make up our thoughts will probably differ. If my thought differs from yours, how can we know when we're thinking about the same thing? How do I make sure that the content of my thought is understood by you?

This set of exercises encourages you to think critically about how the mind represents objects to itself. By making several drawings of the same subject under different restrictions, you will examine how the mind makes an image of an object and how it uses that image in performing different operations.

Lab Exercises:

Each of you will do three drawings of Egon Schiele’s "Portrait of Dr. Ernst Wagner." Please take your time and do the best drawing possible. Each drawing should take ten to fifteen minutes.

Drawing #1: Draw from memory. Closely examine the copy of the portrait, shown on the overhead projector. It is a simple line drawing with a great deal of expressiveness. In the space of five minutes, do your best to 'memorize' the drawing. I will turn the projector off and you will draw it from memory.

Discussion Points:

1. To what extent is your memory drawing a 'good' copy of Schiele’s portrait? Were there any features of the original drawing that did not make it into your rendition?

2. What is the greatest success of your memory drawing? In other words, what feature of your drawing makes it an obvious copy of its original? What is the greatest failing of your memory drawing?

3. What is the most difficult aspect of drawing from memory?

Drawing #2: Draw "The Portrait of Dr. Ernst Wagner" 'from life'. Take time to look closely at the image shown through the overhead projector. Do your best to copy that image exactly onto your page.

Discussion Points:

1. Is drawing #2 a better copy than drawing #1? If so, why? If not, then what quality does the memory drawing have that your 'life' drawing lacks?

2. Does having a copy of the portrait in front of you make it easier to draw it? Why?

3. What is the most difficult aspect of drawing from life?

Drawing #3: Draw the portrait upside down. I will flip the projector image upside down. Copy the upside down version, once again paying careful attention to detail.

Discussion Points:

1. How does this drawing compare with the other two? Is it more or less accurate? More or less expressive?

2. Which is more difficult, drawing 'from life' as in drawing #2, or as in drawing #3? Why do you think one way is easier than the other?

3. What is the most difficult aspect of drawing upside down?

Now that you've watched your mind in action, try to figure out how it does what it does. Note that in each drawing you had the same subject matter, but each drawing looks different. Why might this be the case? If your mind forms a thought of the portrait and then 'tells' your hand to draw it, why doesn't the same drawing result in each case? We might claim that, in each case, your mind has a different thought of it, but this seems like a pretty cumbersome way for your mind to go about its business -- coming up with a brand new thought of something every time you think it. For a final exercise, label the back of each of your drawings as a memory, life, or upside down drawing. The class will divide into groups and your group will give all of its drawings to another group while receiving that group's drawings. Keep the drawings face up (i.e., do not look to see which of them are memory drawings, life drawings, etc.) and jointly decide which drawings are from memory, which are from life, and which are upside down. Make a separate pile for each kind of drawing. Once again, DO NOT cheat and peek on the back of individual drawings. When you have completed your sorting, discuss together what sorts of qualities are had by each of the different kinds of drawing. Do these different qualities indicate that the brain is using different operations or systems to make each kind of drawing? After you have pondered this for a while, check the accuracy of your groupings by looking at the notation on the back of each drawing.

Overview: Work with your partner to prepare a joint lab report addressing the issues below. You should finish this report tonight, hopefully by 9:15 but certainly by 11. You can hand it in here or through email to dan.lloyd. If you write by hand, please try to write neatly.

One approach to writing this: Discuss with your partner what you want the report to say, and outline your group answer to each question. Then divide the labor of writing. After each of you has a draft of your section, exchange seats for final editing.

2. What evidence or observations did you collect tonight in support of your statement in question 1?

3. Consider this passage from the scene of Duncan's murder in Act II of Macbeth.

Is this a dagger which I see before me,

The handle toward my hand? Come, let me clutch thee:

I have thee not, and yet I see thee still.

Art thou not, fatal vision, sensible

To feeling as to sight? or art thou but

A dagger of the mind, a false creation,

Proceeding from the heat-oppressed brain?

Consider the relationship between Macbeth's hallucination of a dagger and your 'seeing' of the portrait by Schiele. What properties to each kind of thought have in common? How are they different?

Before turning to the lab, write down a one or two paragraph answer to each of the following questions.

1. What sort of thing is a 'brain token'? How is it like a written or spoken symbol? How is it different from a written or spoken symbol? (If you like, you can use a brain token of your math teacher as an example.)

2. How do the 'rules of reason' work? What principles guide clear and rational thinking?