Introduction to Philosophy

The Chinese Room

             Functionalism is the doctrine that minds exist because, and only because, some systems, usually but not necessarily human brains, perform certain functions. The functions in question are of course all information processing functions. According to this theory, you have a mind because, and only because your brain processes certain information in certain ways. According to this theory, you have the particular mind you do because your particular brain processes information in its own particular way. Your personality, your preferences, desires, hopes, fears and dreams are all encoded in the structure of your brain. You exist as the person you are because your brain works the way it does.
             Functionalism is actually a pretty obvious implication of the mind brain identity theory. Mind brain identity theory holds that minds only exist because brains do what they do. From this it follows that whenever a brain does the kinds of things that make a mind exist, a mind will exist. A healthy, normally functioning human brain will produce a conscious, thinking mind whenever it performs those normal functions. But if minds exist whenever brains do those brain-functions, minds will also exist whenever anything does those functions, even if the thing during the functions is not itself a human brain. So, if mind brain identity theory is true, functionalism is necessarily also true.
             An important objection to functionalism was articulated by the philosopher John Searle. Searle points out that there is a difference between computation and semantics. To see this difference, think about the difference between the speech recognition software I am using to write my materials for this class, and a human stenographer who transcribes dictation. Both systems take in a stream of words but where the mechanical system could not possibly understand anything that I say, the human stenographer will understand absolutely everything. This is a vitally important difference. The only reason the stenographer can understand what I dictate is because the stenographer has a mind, and understanding is one of the functions of the mind. The mechanical system cannot possibly understand the words it is hearing, and so it cannot possibly have a mind.
             Searle's objection is that computers and computer-like systems will only ever be able to do the kinds of things that speech recognition systems do, which is mechanically convert strings of symbols into other strings of symbols without understanding anything. They will never be able to do what human beings do, which is convert strings of symbols into forms of conscious understanding. There is a story about the emperor Caligula, and how he died. Supposedly, Caligula would periodically call for the captain of his guard and give him a list of people to be executed that day. One day, Caligula decided that the captain of the guard should himself be executed. Unfortunately for him, he issued the execution order in his usual manner. The Captain of the guard read the list, saw his own name on it, and decided to kill Caligula instead of having himself executed. (It doesn't really matter how Caligula died, as long as it was painful.) The point here is that, if Searle is correct, a robot Captain of the guard would not have recognized that his name on the list meant that he would be executed, and so a robot Captain of the guard would have passed on the order without understanding its meaning.
             Another way to understand Searle's objection is to consider the issue of what is called the "Turing Test." The Turing test is basically a failed attempt to determine the appropriate criterion for deciding when a computer is producing a mind. Alan Turing, inventor of the device we now call a "computer" and founder of modern computational theory, was once asked when computers would become conscious. ("Consciousness" is not the same as "mind," but that doesn't matter here.) Turing replied that computers would be conscious when human beings could not tell the difference between a computer and another human being purely on the basis of verbal output. Imagine that you are in a room with nothing but a computer terminal. The screen suddenly displays the word "hello," and you reply by typing in a response. A conversation follows. Now imagine that there are two possibilities. The first is that the computer is connected to another terminal being operated by a human being. The second is that the computer is connected to another computer that is running some piece of software designed to make you think that you are interacting with a human being. Turing's answer to the question of when computers would be conscious was to say that computers would be conscious when you couldn't tell the difference between a computer and a human being on the other end of a communication system like this.
             The problem with the Turing test is that it is possible to write programs that people cannot distinguish from human beings without those programs being conscious. A program called PC Therapist II regularly fools people into thinking that it is a real human being. It does so by taking its input and repackaging it in the form of "active listening" questions. Although it sounds like it understands, all it is doing is taking keywords from its input and reshuffling them into thoughtful looking sentences. Although some people, especially those who know how this program works, can distinguish between the software and a human being it seems clear that the software could be expanded to avoid the giveaways, and to supply more and more outputs on the type that characterize real human thinking. And so I at least think it is possible to write a sophisticated program that takes input that it does not understand, re shuffles and processes it in various ways to create mindless output that is indistinguishable from the kind of output produced by real thinking human beings. I think that if the programmers are bound and determined to create a program that absolutely no one will be able to distinguish from a real program, they will eventually be able to do it, and they will be able to do it without actually making the program actually able to understand any of its inputs. In other words, I think the Turing test is too easy.
             John Searle believes that no computer program will ever be able to produce a mind because, he thinks, computers cannot ever understand the symbols they manipulate. He bases his argument on the following thought experiment. Imagine there is a man who does not understand written Chinese, but who is very good at recognizing and remembering symbols, and at looking things up based on symbols that are incomprehensible to him. This man is placed in a room with several thousand numbered books. This room is separated from the outside world by a door with a small slit in it. Messages are passed in through this slit. These messages are written in Chinese. The man does not read Chinese, but he is able to look up symbols. When he gets a message he looks up the first symbol in book number one. When he finds that symbol, he also finds next to it the number of another book in which to look up the second symbol. This next book directs him to another book, and so on until finally some book or combination of books directs him to write down a new sequence of Chinese characters, none of which he understands. He then passes this response out through the slit.

Outside of the room there is a woman who does understand Chinese. The messages she writes and passes into the room are general knowledge questions, written in Chinese. Because of the way information is encoded in the enormous library of books in the room, the messages written but not understood by the man in the room constitute answers to those general knowledge questions. Searle's argument rests on the claim that it is obvious that the Chinese room does absolutely everything that a computer ever could do in the way of processing symbols according to rules, and that it is obvious to the room does not understand Chinese. And, it may even be true that the room passes the Turing test, because the woman outside might come to believe that the room contains a human being who actually understands Chinese. But this is not so, because the man in the room would not know the difference between a set of translation rules that gave meaningful answers to serious questions, and a set of translation rules that returned absolute gibberish. We can imagine someone sneaking in and replacing a couple of the books so that the room starts producing nonsense. The woman outside would notice the difference because she understands Chinese, but the man in the room would have absolutely no idea that anything was amiss. From this, Searle draws the conclusion that mere computations can never produce a mind because mere computations can never constitute understanding in the sense that the woman outside understands Chinese, and the man inside doesn't.

If you'd like more information:

In Defence of Strong AI: Semantics from Syntax

Essay Topic Question: Does the Chinese Room thought experiment refute functionalism? Think this through from all sides before you start writing. Come up with reasons for and against the idea that this argument refutes functionalism, and figure out for yourself whether you think it does or not. When you've thunk it through, write an odyssey paper explaining all your thinking, especially what you think, why you think it, and why you don't agree with the opposing arguments.

Hints:

Does Searle ever define meaning?
Does Searle ever explain how human brains establish meaning?
What is meaning, anyway?
Does Searle ever show that the Chinese Room represents the only way a computer can work?
Does Searle prove that the Chinese Room represents the only way a computer can interact with its environment?
Does Searle prove that computer programs can never do the same things as neurons?
Does Searle prove that computer logic structures can never do the same things as arrangements of neurons?
Does Searle prove that computers can never do the exact things that human brains do to create meaning?