(source)
4. Searle's Chinese Room Argument
As we have seen, the idea that a certain type of symbol processing can be what makes something an intentional system is fundamental to the computer model of the mind. Let us now turn to a flamboyant frontal attack on this idea by John Searle (1980, 1990b, Churchland and Churchland, 1990; the basic idea of this argument stems from Block, 1978). Searle's strategy is one of avoiding quibbles about specific programs by imagining that cognitive science of the distant future can come up with the program of an actual person who speaks and understands Chinese, and that this program can be implemented in a machine. Unlike many critics of the computer model, Searle is willing to grant that perhaps this can be done so as to focus on his claim that even if this can be done, the machine will not have intentional states.
The argument is based on a thought experiment. Imagine yourself given a job in which you work in a room (the Chinese room). You understand only English. Slips of paper with Chinese writing on them are put under the input door, and your job is to write sensible Chinese replies on other slips, and push them out under the output door. How do you do it? You act as the CPU (central processing unit) of a computer, following the computer program mentioned above that describes the symbol processing in an actual Chinese speaker's head. The program is printed in English in a library in the room. This is how you follow the program. Suppose the latest input has certain unintelligible (to you) Chinese squiggles on it. There is a blackboard on a wall of the room with a "state" number written on it; it says `17'. (The CPU of a computer is a device with a finite number of states whose activity is determined solely by its current state and input, and since you are acting as the CPU, your output will be determined by your intput and your "state". The `17' is on the blackboard to tell you what your "state" is.) You take book 17 out of the library, and look up these particular squiggles in it. Book 17 tells you to look at what is written on your scratch pad (the computer's internal memory), and given both the input squiggles and the scratch pad marks, you are directed to change what is on the scratch pad in a certain way, write certain other squiggles on your output pad, push the paper under the output door, and finally, change the number on the state board to `193'. As a result of this activity, speakers of Chinese find that the pieces of paper you slip under the output door are sensible replies to the inputs..
But you know nothing of what is being said in Chinese; you are just following instructions (in English) to look in certain books and write certain marks. According to Searle, since you don't understand any Chinese, the system of which you are the CPU is a mere Chinese simulator, not a real Chinese understander. Of course, Searle (rightly) rejects the Turing Test for understanding Chinese. His argument, then is that since the program of a real Chinese understander is not sufficient for understanding Chinese, no symbol-manipulation theory of Chinese understanding (or any other intentional state) is correct about what makes something a Chinese understander. Thus the conclusion of Searle's argument is that the fundamental idea of thought as symbol processing is wrong even if it allows us to build a machine that can duplicate the symbol processing of a person and thereby duplicate a person's behavior.
The best criticisms of the Chinese room argument have focused on what Searle--anticipating the challenge--calls the systems reply. (See the responses following Searle (1980), and the comment on Searle in Hofstadter and Dennett (1981).) The systems reply has a positive and a negative component. The negative component is that we cannot reason from "Bill has never sold uranium to North Korea" to "Bill's company has never sold uranium to North Korea". Similarly, we cannot reason from "Bill does not understand Chinese" to "The system of which Bill is a part does not understand Chinese. (See Copeland, 1993b.) There is a gap in Searle's argument. The positive component goes further, saying that the whole system--man + program + board + paper + input and output doors--does understand Chinese, even though the man who is acting as the CPU does not. If you open up your own computer, looking for the CPU, you will find that it is just one of the many chips and other components on the main circuit-board. The systems reply reminds us that the CPUs of the thinking computers we hope to have someday will not themselves think--rather, they will be parts of thinking systems.
Searle's clever reply is to imagine the paraphernalia of the "system" internalized as follows. First, instead of having you consult a library, we are to imagine you memorizing the whole library. Second, instead of writing notes on scratch pads, you are to memorize what you would have written on the pads, and you are to memorize what the state blackboard would say. Finally, instead of looking at notes put under one door and passing notes under another door, you just use your own body to listen to Chinese utterances and produce replies. (This version of the Chinese room has the additional advantage of generalizability so as to involve the complete behavior of a Chinese-speaking system instead of just a Chinese note exchanger.) But as Searle would emphasize, when you seem to Chinese speakers to be conducting a learned discourse with them in Chinese, all you are aware of doing is thinking about what noises the program tells you to make next, given the noises you hear and what you've written on your mental scratch pad.
I argued above that the CPU is just one of many components. If the whole system understands Chinese, that should not lead us to expect the CPU to understand Chinese. The effect of Searle's internalization move--the "new" Chinese Room--is to attempt to destroy the analogy between looking inside the computer and looking inside the Chinese Room. If one looks inside the computer, one sees many chips in addition to the CPU. But if one looks inside the "new" Chinese Room, all one sees is you, since you have memorized the library and internalized the functions of the scratchpad and the blackboard. But the point to keep in mind is that although the non-CPU components are no longer easy to see, they are not gone. Rather, they are internalized. If the program requires the contents of one register to be placed in another register, and if you would have done this in the original Chinese Room by copying from one piece of scratch paper to another, in the new Chinese Room you must copy from one of your mental analogs of a piece of scratch paper to another. You are implementing the system by doing what the CPU would do and you are simultaneously simulating the non-CPU components. So if the positive side of the systems reply is correct, the total system that you are implementing does understand Chinese.
"But how can it be", Searle would object, "that you implement a system that understands Chinese even though you don't understand Chinese?" The systems reply rejoinder is that you implement a Chinese understanding system without yourself understanding Chinese or necessarily even being aware of what you are doing under that description. The systems reply sees the Chinese Room (new and old) as an English system implementing a Chinese system. What you are aware of are the thoughts of the English system, for example your following instructions and consulting your internal library. But in virtue of doing this Herculean task, you are also implementing a real intelligent Chinese-speaking system, and so your body houses two genuinely distinct intelligent systems. The Chinese system also thinks, but though you implement this thought, you are not aware of it.
The systems reply can be backed up with an addition to the thought experiment that highlights the division of labor. Imagine that you take on the Chinese simulating as a 9-5 job. You come in Monday morning after a weekend of relaxation, and you are paid to follow the program until 5 PM. When you are working, you concentrate hard at working, and so instead of trying to figure out the meaning of what is said to you, you focus your energies on working out what the program tells you to do in response to each input. As a result, during working hours, you respond to everything just as the program dictates, except for occasional glances at your watch. (The glances at your watch fall under the same category as the noises and heat given off by computers: aspects of their behavior that is not part of the machine description but are due rather to features of the implementation.) If someone speaks to you in English, you say what the program (which, you recall, describes a real Chinese speaker) dictates. So if during working hours someone speaks to you in English, you respond with a request in Chinese to speak Chinese, or even an inexpertly pronounced "No speak English," that was once memorized by the Chinese speaker being simulated, and which you the English speaking system may even fail to recognize as English. Then, come 5 PM, you stop working, and react to Chinese talk the way any monolingual English speaker would.
Why is it that the English system implements the Chinese system rather than, say, the other way around? Because you (the English system whom I am now addressing) are following the instructions of a program in English to make Chinese noises and not the other way around. If you decide to quit your job to become a magician, the Chinese system disappears. However, if the Chinese system decides to become a magician, he will make plans that he would express in Chinese, but then when 5 P.M. rolls around, you quit for the day, and the Chinese system's plans are on the shelf until you come back to work. And of course you have no commitment to doing whatever the program dictates. If the program dictates that you make a series of movements that leads you to a flight to China, you can drop out of the simulating mode, saying "I quit!" The Chinese speaker's existence and the fulfillment of his plans depends on your work schedule and your plans, not the other way around.
Thus, you and the Chinese system cohabit one body. In effect, Searle uses the fact that you are not aware of the Chinese system's thoughts as an argument that it has no thoughts. But this is an invalid argument. Real cases of multiple personalities are often cases in which one personality is unaware of the others.
It is instructive to compare Searle's thought experiment with the string-searching Aunt Bubbles machine described at the outset of this paper. This machine was used against a behaviorist proposal of a behavioral concept of intelligence. But the symbol manipulation view of the mind is not a proposal about our everyday concept. To the extent that we think of the English system as implementing a Chinese system, that will be because we find the symbol-manipulation theory of the mind plausible as an empirical theory.
There is one aspect of Searle's case with which I am sympathetic. I have my doubts as to whether there is anything it is like to be the Chinese system, that is, whether the Chinese system is a phenomenally conscious system. My doubts arise from the idea that perhaps consciousness is more a matter of implementation of symbol processing than of symbol processing itself. Though surprisingly Searle does not mention this idea in connection with the Chinese Room, it can be seen as the argumentative heart of his position. Searle has argued independently of the Chinese Room (Searle, 1992, Ch 7) that intentionality requires consciousness. (See the replies to Searle in Behavioral and Brain Sciences 13, 1990.) But this doctrine, if correct, can shore up the Chinese Room argument. For if the Chinese system is not conscious, then, according to Searle's doctrine, it is not an intentional system either.
Even if I am right about the failure of Searle's argument, it does succeed in sharpening our understanding of the nature of intentionality and its relation to computation and representation.