Problem Set 04

Problem Set 04

1. The English Reply

Boden (Margaret Boden, "Escaping from the Chinese Room") defends the following response to Searle's Chinese Room Thought Experiment:

The crux of the English reply is that the instantiation of a computer program, whether by man or by manufactured machine, does involve understanding-at least of the rule-book. Searle's initial example depends critically on Searle-in-the-room's being able to understand the language in which the rules are written, namely English; similarly, without Searle-inthe-robot's familiarity with English, the robot's beansprouts would never get thrown into the wok. Moreover, as remarked above, the vocabulary of English (and, for Se arle-in-the-robot, of Chinese too) would have to be significantly modified to make the example work.

An unknown language (whether Chinese or Linear B) can be dealt with only as an aesthetic object or a set of systematically related forms. Artificial languages can be designed and studied, by the logician or the pure mathematician, with only their structural properties in mind (although D. R. Hofstadter's (1979) example of the quasi-arithmetical pq-system shows that a psychologically compelling, and predictable, interpretation of a formal calculus may arise spontaneously). But one normally responds in a very different way to the symbols of one's native tongue; indeed, it is very difficult to 'bracket' (ignore) the meanings of familiar words. The view held by computational psychologists, that natural languages can be characterized in procedural terms, is relevant here: words, clauses, and sentences can be seen as mini-programs. The symbols in a natural language one understands initiate mental activity of various kinds. To learn a language is to set up the relevant causal connections, not only between words and the world ('cat' and the thing on the mat) but between words and the many non-introspectible procedures involved in interpreting them.

Moreover, we do not need to be told ex hypothesi (by Searle) that Searle-in-the-room understands English: his behaviour while in the room shows clearly that he does. Or, rather, it shows that he understands a highly limited subset of English.

Searle-in-the-room could be suffering from total amnesia with respect to 99 per cent of Searle's English vocabulary, and it would make no difference. The only grasp of English he needs is whatever is necessary to interpret the rule-book-which specifies how to accept, select, compare, and give out different patterns. Unlike Searle, Searle-in-the-room does not require words like 'catalyse', 'beer-can', 'chlorophyll'. and 'restaurant'. But he may need 'find', 'compare', 'two', 'triangular', and 'window' (although his understanding of these words could be much less full than Searle's). He must understand conditional sentences, if any rule states that if he sees a squoggle he should give out a squiggle. Very likely, he must understand some way of expressing negation, temporal ordering, and (especially if he is to learn to do his job faster) generalization. If the rules he uses include some which parse the Chinese sentences, then he will need words for grammatical categories too. (He will not need explicit rules for parsing English sentences, such as the parsing procedures employed in AI programs for language-processing, because he already understands English.)

In short, Searle-in-the-room needs to understand only that subset of Searle's English which is equivalent to the programming-language understood by a computer generating the same 'question-answering' input-output behaviour at the window. Similarly, Searle-in-the-robot must be able to understand whatever subset of English is equivalent to the programming-language understood by a fully computerized visuomotor robot.

In a long essay, set out and explain the English Reply for the untutored--that is, explain it for someone not in the class, someone who, for example, has never heard of the distinction between original and derived intentionality. To be clear, your point in this is neither to criticize nor defend the English Reply. Rather, simply explain it in as paintstaking a fashion as a long essay permits. (25pts)

2. The Causal Role of Intentional States

In a long essay, explain the following passage from Dretske's article, "Minds, Machines, and Money: What Really Explains Behavior": (25)

If we think of ourselves as "vending machines" whose internal causal structure is designed, shaped, and modified not, as with vending machines, by engineers, but, in the first instance, by evolution and, in the second, by learning, then we can say that although it is the "size" and "shape" (the syntax, as it were) of the internal causes that make the body move the way it does (just as it is the size and shape of the coins that releases the Cokes) it is, or may be, the fact that a certain extrinsic property supervenes on that neurological "size" and "shape" that explains why internal events having these intrinsic properties have the effect on the body that they have. What explains why a certain neurological event in the visual cortex of a chicken - an event caused by the shadow of an overhead hawk - causes the chicken to cower and hide is the fact that such neurological events have a significant (to chickens) extrinsic property - the property of normally being caused by predatory hawks. It is, or may be, possession of this extrinsic property - what the internal events indicate about external affairs - that explains why objects having those intrinsic properties cause what they do.

There is but a short step from here to the conclusion that it is the extrinsic, not the intrinsic, properties of internal events that causally explain behavior. All that is needed to execute this step is the premise that behavior is not the bodily movements that internal events cause, but the causing of these movements by internal events. All that is required, that is, is an appropriate distinction between the behavior that beliefs explain and the bodily movements that (in part) constitute that behavior. For if moving your arms and legs (behavior) is not the same as the movements of the arms and legs, but it is, rather, some internal event causing the arms and legs to move, then although the intrinsic properties of our internal "coins" will explain (via activation of muscles) the movements of our arms and legs, the extrinsic properties, properties having to do with what external conditions these internal events are correlated with, will explain why we move them.