March 21 The Chinese Room objection to the computational theory of mind; Locke on words and ideas Part I

The Chinese Room The computational story about language-understanding

If the computational theory of mind is right, then there exists a set of instructions that can be followed to tell you how to process language you hear.

It follows that a fluent speaker of Chinese understands her language because her brain is a Turing machine executing a program that works in the right way, delivering the right outputs. The “Chinese Room” thought experiment

John Searle famously made this objection in 1980 to the computational theory of mind. He had predecessors!

I Gottfried Leibniz in 1714 imagined the brain expanded so that you could walk around within it; he found it hard to imagine that such a thing could have consciousness, and concluded that our mental life cannot be due to the physical functioning of our brains.

I We’ve already seen Ned Block’s “China Brain” thought experiment; Searle’s is a tweak on that. The “Chinese Room” thought experiment

The scenario Suppose we have a fluent speaker of Chinese; let’s call her Song. Suppose also that we know how her brain works—how it does its computations.

Now suppose that the instructions specifying how Song’s brain processes Chinese are written in English and given to a speaker of English, namely, John Searle. The “Chinese Room” thought experiment

Searle does the following in his Room:

I receives Chinese writing—expressing a story, some relevant background facts, and some questions about the story—slipped through the door;

I follows the instructions—written in English—for processing the Chinese writing;

I writes Chinese symbols on pieces of paper, as his “output.” Since the instructions duplicate Song’s computer/brain, the output is the output that she would give. She understands the story, but Searle doesn’t. The “Chinese Room” thought experiment

Searle’s conclusion: computation does not suffice for understanding. The “Chinese Room” thought experiment

By hypothesis, Searle does the same computations that Song’s brain does.

But, Searle says, Searle doesn’t understand Chinese. So the computational concept of mind is false! The “Chinese Room” thought experiment

Fodor’s “reply” (93):

I Searle, in the Room, won’t know what relations the Chinese symbols stand in to the world (e.g. how and when they’re used).

I So, he won’t know their semantic properties (roughly: what those symbols stand for).

I So, he won’t understand them. Therefore he won’t understand the story. (I can’t see that this is much of a reply to the argument, since Searle’s whole point is that he won’t understand the story.) Part II

“Content” The word “content”

I Some mental states are about objects or states of affairs

I They represent them Philosophers use the word “content” to get at this feature that many of our mental states have. The word “content”

What a mental state is about is sometimes called the content of that state. The content of Bloggs’s belief that Mt Everest is 8,848 meters high is the following state of affairs: Everest is 8,848 meters high. (125–26)

We specify a state’s content by using a “that”-clause: Bloggs believes that Mt Everest is 8,848 meters high. Part III

Locke on what words mean Locke on what words signify

There is no natural connection between particular sounds and particular ideas. . . but people arbitrarily chose to use use such and such a word as the mark of such and such an idea. (III.ii.1)

Words stand for ideas. “Gold” doesn’t stand for the metal that we make into coins.

But what are ideas? Ideas

I They’re things that “the mind perceives in itself” (II.viii.7)

I Ideas are caused by the “qualities” of things (II.viii.8)

I This happens when bodies “impact” us (II.viii.10) Now—there are two kinds of qualities, and they relate to ideas differently. Qualities

There are primary and secondary qualities. Some qualities are “utterly inseparable from the body”

I e.g. solidity; shape These are primary qualities. Others are “powers to produce various sensations in us by their primary qualities”

I e.g. colours, sounds, tastes These are secondary qualities. “From this we can easily infer” that qualities of the former sort cause in us ideas that “resemble” them (II.viii.15). Writing assignment . . . the ideas of the primary qualities of bodies resemble them, and their patterns really do exist in the bodies themselves; but the ideas produced in us by secondary qualities don’t resemble them at all. (Book II, chapter viii, section 15)

I Give an instance of each of the two general claims Locke is making here.

I Try to explain what he might mean by “resembles.” What sort of relationship does Locke seem to mean by that word? How could one tell when it obtains (between some idea and the quality that caused it)?

I Test your interpretation by seeing if the results it gives for the two examples are the results that Locke wants. (It’s ok if it doesn’t! Just try to be clear in your explanation.)