I take it we have a division within the ranks. Why doesn't LS want to be friends with Virtuoso? We have enough enemies, let us not waste our energy bickering amongst ourselves lest we shall lose altogether.
There's a new world somewhere They call The Promised Land And I'll be there some day If you will hold my hand I still need you there beside me No matter what I do For I know I'll never find another you There is always someone For each of us they say And you'll be my someone For ever and a day I could search the whole world over Until my life is through But I know I'll never find another you It's a long, long journey [/b]So stay by my side[/b] When I walk through the storm You'll be my guide, be my guide If they gave me a fortune My treasure would be small I could lose it all tomorrow And never mind at all But if I should lose your love, dear[/szie] I don't know what I'll do For I know I'll never find another you But if I should lose your love, dear I don't know what I'll do For I know I'll never find another you Another you, another you :-/
A Coffeehouse Conversation on the Turing Test May, 1981 Douglas R. Hofstadter Participants in the dialog: Chris, a physics student; Pat, a biology student; Sandy, a philosophy student. Chris: Sandy, I want to thank you for suggesting that I read Alan Turing's article "Computing Machinery and Intelligence." It's a wonderful piece and certainly made me think-and think about my thinking. Sandy: Glad to hear it. Are you still as much of a skeptic about artificial intelligence as you used to be? Chris: You've got me wrong. I'm not against artificial intelligence; I think it's wonderful stuff-perhaps a little crazy, but why not? I simply am convinced that you AI advocates have far underestimated the human mind, and that there are things a computer will never, ever be able to do. For instance, can you imagine a computer writing a Proust novel? The richness of imagination, the complexity of the characters- Sandy: Rome wasn't built in a day! Chris: In the article, Turing comes through as an interesting person. Is he still alive? Sandy: No, he died back in 1954, at just 41. He'd be only 70 or so now, although he is such a legendary figure it seems strange to think that he could still be living today. Chris: How did he die? Sandy: Almost certainly suicide. He was homosexual, and had to deal with some pretty barbaric treatment and stupidity from the outside world. In the end, it got to be too much, and he killed himself. Chris: That's horrendous, especially in this day and age. Sandy: I know. What really saddens me is that he never got to see the amazing progress in computing machinery and theory that has taken place since 1954. Can you imagine how he'd have been wowed? Chris: Yeah . . . Pat: Hey, are you two going to clue me in as to what this Turing article is about? Sandy: It is really about two things. One is the question "Can a machine think?"-or rather, "Will a machine ever think?" The way Turing answers the question-he thinks the answer is yes, by the way-is by batting down a series of objections to the idea, one after another. The other point he tries to make is that, as it stands, the question is not meaningful. It's too full of emotional connotations. Many people are upset by the suggestion that people are machines, or that machines might think. Turing tries to defuse the question by casting it in less emotional terms. For instance, what do you think, Pat, of the idea of thinking machines? Pat: Frankly, I find the term confusing. You know what confuses me? It's those ads in the newspapers and on TV that talk about "products that think" or "intelligent ovens" or whatever. I just don't know how seriously to take them. Sandy: I know the kind of ads you mean, and they probably confuse a lot of people. On the one hand, we're always hearing the refrain "Computers are really dumb; you have to spell everything out for them in words of one syllable"-yet on the other hand, we're constantly bombarded with advertising hype about "smart products." Chris: That's certainly true. Do you know that one company has even taken to calling its products "dumb terminals" in order to stand out from the crowd? Sandy: That's a pretty clever gimmick, but even so it just contributes to the trend toward obfuscation. The term "electronic brain" always comes to my mind when I'm thinking about this. Many people swallow it completely, and others reject it out of hand. It takes patience to sort out the issues and decide how much of it makes sense. Pat: Does Turing suggest some way of resolving it, some kind of IQ test for machines? Sandy: That would be very interesting, but no machine could yet come close to taking an IQ test. Instead, Turing proposes a test that theoretically could be applied to any machine to determine whether or not it can think. Pat: Does the test give a clear-cut yes-or-no answer? I'd be skeptical if it claimed to. Sandy: No, it doesn't claim to. In a way that's one of its advantages. It shows how the borderline is quite fuzzy and how subtle the whole question is.
Pat: And so, as usual in philosophy, it's all just a question of words! Sandy: Maybe, but they're emotionally charged words, and so it's important, it seems to me, to explore the issues and try to map out the meanings of the crucial words. The issues are fundamental to our concept of ourselves. So we shouldn't just sweep them under the rug. Pat: Okay, so tell me how Turing's test works. Sandy: The idea is based on what he calls the Imitation Game. Imagine that a man and a woman go into separate rooms, and from there they can be interrogated by a third party via some sort of teletype set-up. The third party can address questions to either room, but has no idea which person is in which room. For the interrogator, the idea is to determine which room the woman is in. The woman, by her answers, tries to help the interrogator as much as she can. The man, though, is doing his best to bamboozle the interrogator, by responding as he thinks a woman might. And if he succeeds in fooling the interrogator... Pat: The interrogator only gets to see written words, eh? And the sex of the author is supposed to shine through? That game sounds like a good challenge. I'd certainly like to take part in it someday. Would the interrogator have met either the man or the woman before the test began? Would any of them know any of the others? Sandy: That would probably be a bad idea. All kinds of subliminal cueing might occur if the interrogator knew one or both of them. It would certainly be best if all three people were totally unknown to one another. Pat: Could you ask any questions at all, with no holds barred? Sandy: Absolutely. That's the whole idea! Pat: Don't you think, then, that pretty quickly it would degenerate into sex-oriented questions? I mean, I can imagine the man, overeager to act convincing, giving away the game by answering some very blunt questions that most women would find too personal to answer, even through an anonymous computer connection. Sandy: That's a nice observation. I wonder if it's true .... Chris: Another possibility would be to probe for knowledge of minute aspects of traditional sex-role differences, by asking about such things as dress sizes and so on. The psychology of the Imitation Game could get pretty subtle. I suppose whether the interrogator was a woman or a man would make a difference. Don't you think that a woman could spot some telltale differences more quickly than a man could? Pat: If so, maybe the best way to tell a man from a woman is to let each of them play interrogator in an Imitation Game and see which of the two is better at telling a man from a woman! Sandy: Hmm . . . that's a droll twist. Oh well, I don't know if this original version of the Imitation Game has ever been seriously tried out, despite the fact that it would be relatively easy to do with modern computer terminals. I have to admit, though, that I'm not at all sure what it would prove, whichever way it turned out. Pat: I was wondering about that. What would it prove if the interrogator-say a woman-couldn't tell correctly which person was the woman? It certainly wouldn't prove that the man was a woman! Sandy: Exactly! What I find funny is that although I strongly believe in the idea of the Turing Test, I'm not so sure I understand the point of its basis, the Imitation Game. Chris: As for me, I'm not any happier with the Turing Test as a test for thinking machines than I am with the Imitation Game as a test for femininity. Pat: From what you two are saying, I gather the Turing Test is some kind of extension of the Imitation Game, only involving a machine and a person instead of a man and a woman. Sandy: That's the idea. The machine tries its hardest to convince the interrogator that it is the human being, and the human tries to make it clear that he or she is not the computer.
Pat: The machine tries? Isn't that a loaded way of putting it? Sandy: Sorry, but that seemed the most natural way to say it. Pat: Anyway, this test sounds pretty interesting. But how do you know that it will get at the essence of thinking? Maybe it's testing for the wrong things. Maybe, just to take a random illustration, someone would feel that a machine was able to think only if it could dance so well that you couldn't tell it was a machine. Or someone else could suggest some other characteristic. What's so sacred about being able to fool people by typing at them? Sandy: I don't see how you can say such a thing. I've heard that objection before, but frankly, it baffles me. So what if the machine can't tap-dance or drop a rock on your toe? If it can discourse intelligently on any subject you want, then it has shown that it can think-to me, at least! As I see it, Turing has drawn, in one clean stroke, a clear division between thinking and other aspects of being human. Pat: Now you're the baffling one. If you couldn't conclude anything from a man's ability to win at the Imitation Game, how could you conclude anything from a machine's ability to win at the Turing Game? Chris: Good question. Sandy: It seems to me that you could conclude something from a man's win in the Imitation Game. You wouldn't conclude he was a woman, but you could certainly say he had good insights into the feminine mentality (if there is such a thing). Now, if a computer could fool someone into thinking it was a person, I guess you'd have to say something similar about it-that it had good insights into what it's like to be human, into "the human condition" (whatever that is). Pat: Maybe, but that isn't necessarily equivalent to thinking, is it? It seems to me that passing the Turing Test would merely prove that some machine or other could do a very good job of simulating thought. Chris: I couldn't agree more with Pat. We all know that fancy computer programs exist today for simulating all sorts of complex phenomena. In theoretical physics, for instance, we simulate the behavior of particles, atoms, solids, liquids, gases, galaxies, and so on. But no one confuses any of those simulations with the real thing! Sandy: In his book Brainstorms, the philosopher Daniel Dennett makes a similar point about simulated hurricanes. Chris: That's a nice example, too. Obviously, what goes on inside a computer when it's simulating a hurricane is not a hurricane, for the machine's memory doesn't get torn to bits by 200 mile-an-hour winds, the floor of the machine room doesn't get flooded with rainwater, and so on. Sandy: Oh, come on-that's not a fair argument! In the first place, the programmers don't claim the simulation really is a hurricane. It's merely a simulation of certain aspects of a hurricane. But in the second place, you're pulling a fast one when you imply that there are no downpours or 200-mile-an-hour winds in a simulated hurricane. To us there aren't any, but if the program were incredibly detailed, it could include simulated people on the ground who would experience the wind and the rain just as we do when a hurricane hits. In their minds-or, if you'd rather, in their simulated minds-the hurricane would be not a simulation, but a genuine phenomenon complete with drenching and devastation. Chris: Oh, my-what a science-fiction scenario! Now we're talking about simulating whole populations, not just a single mind! Sandy: Well, look-I'm simply trying to show you why your argument that a simulated McCoy isn't the real McCoy is fallacious. It depends on the tacit assumption that any old observer of the simulated phenomenon is equally able to assess what's going on. But in fact, it may take an observer with a special vantage point to recognize what is going on. In the hurricane case, it takes special "computational glasses" to see the rain and the winds. Pat: "Computational glasses"? I don't know what you're talking about. Sandy: I mean that to see the winds and the wetness of the hurricane, you have to be able to look at it in the proper way. You- Chris: No, no, no! A simulated hurricane isn't wet! No matter how much it might seem wet to simulated people, it won't ever be genuinely wet! And no computer will ever get torn apart in the process of simulating winds. Sandy: Certainly not, but that's irrelevant. You're just confusing levels. The laws of physics don't get torn apart by real hurricanes, either. In the case of the simulated hurricane, if you go peering at the computer's memory, expecting to find broken wires and so forth, you'll be disappointed. But look at the proper level. Look into the structures that are coded for in memory. You'll see that many abstract links have been broken, many values of variables radically changed, and so on. There's your flood, your devastation-real, only a little concealed, a little hard to detect. Chris: I'm sorry, I just can't buy that. You're insisting that I look for a new kind of devastation, one never before associated with hurricanes. That way you could call anything a hurricane as long as its effects, seen through your special "glasses," could be called "floods and devastation." Sandy: Right-you've got it exactly! You recognize a hurricane by its effects. You have no way of going in and finding some ethereal "essence of hurricane," some "hurricane soul" right in the middle of the storm's eye. Nor is there any ID card to be found that certifies "hurricanehood." It's just the existence of a certain kind of pattern--a spiral storm with an eye and so forth-that makes you say it's a hurricane. Of course, there are a lot of things you'll insist on before you call something a hurricane. Pat: Well, wouldn't you say that being an atmospheric phenomenon is one prerequisite? How can anything inside a computer be a storm? To me, a simulation is a simulation is a simulation! Sandy: Then I suppose you would say that even the calculations computers do are simulated-that they are fake calculations. Only people can do genuine calculations, right? Pat: Well, computers get the right answers, so their calculations are not exactly fake-but they're still just patterns. There's no understanding going on in there. Take a cash register. Can you honestly say that you feel it is calculating something when its gears mesh together? And the step from cash register to computer is very short, as I understand things. Sandy: If you mean that a cash register doesn't feel like a schoolkid doing arithmetic problems, I'll agree. But is that what "calculation" means? Is that an integral part of it? If so, then contrary to what everybody has thought up till now, we'll have to write a very complicated program indeed to perform genuine calculations. Of course, this program will sometimes get careless and make mistakes, and it will sometimes scrawl its answers illegibly, and it will occasionally doodle on its paper .... It won't be any more reliable than the store clerk who adds up your total by hand. Now, I happen to believe that eventually such a program could be written. Then we'd know something about how clerks and schoolkids work. Pat: I can't believe you'd ever be able to do that! Sandy: Maybe, maybe not, but that's not my point. You say a cash register can't calculate. It reminds me of another favorite passage of mine from Dennett's Brainstorms. It goes something like this: "Cash registers can't really calculate; they can only spin their gears. But cash registers can't really spin their gears, either: they can only follow the laws of physics." Bennett said it originally about computers; I modified it to talk about cash registers. And you could use the same line of reasoning in talking about people: "People can't really calculate; all they can do is manipulate mental symbols. But they aren't really manipulating symbols: all they are doing is firing various neurons in various patterns. But they can't really make their neurons fire; they simply have to let the laws of physics make them fire for them." Et cetera. Don't you see how this reduction ad absurdum would lead you to conclude that calculation doesn't exist, that hurricanes don't exist-in fact, that nothing at a level higher than particles and the laws of physic exists? What do you gain by saying that a computer only pushes symbols around and doesn't truly calculate?
Pat: The example may be extreme, but it makes my point that there is a vast difference between a real phenomenon and any simulation of it. This is so for hurricanes, and even more so for human thought. Sandy: Look, I don't want to get too tangled up in this line of argument, but let me try one more example. If you were a radio ham listening to another ham broadcasting in Morse code and you were responding in Morse code, would it sound funny to you to refer to "the person at the other end"? Pat: No, that would sound okay, although the existence of a person at the other end would be an assumption. Sandy: Yes, but you wouldn't be likely to go and check it out. You're prepared to recognize personhood through those rather unusual channels. You don't have to see a human body or hear a voice. All you need is a rather abstract manifestation-a code, as it were. What I'm getting at is this. To "see" the person behind the dits and dahs, you have to be willing to do some decoding, some interpretation. It's not direct perception; it's indirect. You have to peel off a layer or two to find the reality hidden in there. You put on your "radio-ham's glasses" to "see" the person behind the buzzes. Just the same with the simulated hurricane! You don't see it darkening the machine room; you have to decode the machine's memory. You have to put on special "memory-decoding" glasses. Then what you see is a hurricane. Pat: Oh ho ho! Talk about fast ones-wait a minute! In the case of the shortwave radio, there's a real person out there, somewhere in the Fiji Islands or wherever. My decoding act as I sit by my radio simply reveals that that person exists. It's like seeing a shadow and concluding there's an object out there, casting it. One doesn't confuse the shadow with the object, however! And with the hurricane there's no real storm behind the scenes, making the computer follow its patterns. No, what you have is just a shadow hurricane without any genuine hurricane. I just refuse to confuse shadows with reality. Sandy: All right. I don't want to drive this point into the ground. I even admit it is pretty silly to say that a simulated hurricane is a hurricane. But I wanted to point out that it's not as silly as you might think at first blush. And when you turn to simulated thought then you've got a very different matter on your hands from simulated hurricanes. Pat: I don't see why. You'll have to convince me. Sandy: Well, to do so, I'll first have to make a couple of extra points about hurricanes. Pat: Oh no! Well, all right, all right. Sandy: Nobody can say just exactly what a hurricane is-that is, in totally precise terms. There's an abstract pattern that many storms share, and it's for that reason we call those storms hurricanes. But it's not possible to make a sharp distinction between hurricanes and no hurricanes. There are tornados, cyclones, typhoons, dust devils .... Is the Great Red Spot on Jupiter a hurricane? Are sunspots hurricanes? Could there be a hurricane in a wind tunnel? In a test tube? In your imagination, you can even extend the concept of "hurricane" to include a microscopic storm on the surface of a neutron star. Chris: That's not so far-fetched, you know. The concept of "earthquake" has actually been extended to neutron stars. The astrophysicists say that the tiny changes in rate that once in a while are observed in the pulsing of a pulsar are caused by "glitches"starquakes-that have just occurred on the neutron star's surface. Sandy: Oh, I remember that now. That "glitch" idea has always seemed eerie to me-a surrealistic kind of quivering on a surrealistic kind of surface. Chris: Can you imagine-plate tectonics on a giant sphere of pure nuclear matter? Sandy: That's a wild thought. So, starquakes and earthquakes can both be subsumed into a new, more abstract category. And that's how science constantly extends familiar concepts, taking them further and further from familiar experience and yet keeping some essence constant. The number system is the classic example-from positive numbers to negative numbers, then rationale, reels, complex numbers, and "on beyond zebra," as Dr. Seuss says. Pat: I think I can see your point, Sandy. In biology, we have many examples of close relationships that are established in rather abstract ways. Often the decision about what family some species belongs to comes down to an abstract pattern shared at some level. Even the concepts of "male" and "female" turn out to be surprisingly abstract and elusive. When you base your system of classification on very abstract patterns, I suppose that a broad variety of phenomena can fall into "the same class," even if in many superficial ways the class members are utterly unlike one another. So perhaps I can glimpse, at least a little, how to you, a simulated hurricane could, in a funny sense, be a hurricane. Chris: Perhaps the word that's being extended is not "hurricane," but "be." Pat: How so? Chris: If Turing can extend the verb "think," can't I extend the verb "be"? All I mean is that when simulated things are deliberately confused with genuine things, somebody's doing a lot of philosophical wool pulling. It's a lot more serious than just extending a few nouns, such as "hurricane." Sandy: I like your idea that "be" is being extended, but I sure don't agree with you about the wool pulling. Anyway, if you don't object, let me just say one more thing about simulated hurricanes and then I'll get to simulated minds. Suppose you consider a really deep simulation of a hurricane-I mean a simulation of every atom, which I admit is sort of ridiculous, but still, just consider it for the sake of argument. Pat: Okay. Sandy: I hope you would agree that it would then share all the abstract structure that defines the "essence of hurricanehood." So what's to keep you from calling it a hurricane? Pat: I thought you were backing off from that claim of equality. Sandy: So did I, but then these examples came up, and I was forced back to my claim. But let me back off, as I said I would do, and get back to thought, which is the real issue here. Thought, even more than hurricanes, is an abstract structure, a way of describing some complex events that happen in a medium called a brain. But actually, thought can take place in any one of several billion brains. There are all these physically very different brains, and yet they all support "the same thing": thinking. What's important, then, is the abstract pattern, not the medium. The same kind of swirling can happen inside any of them, so no person can claim to think more "genuinely" than any other. Now, if we come up with some new kind of medium in which the same style of swirling takes place, could you deny that thinking is taking place in it?
The rest of the coffehouse conversation can be found here; http://dangermouse.brynmawr.edu/csem/coffeehouse.html I planned on pasting the entire thing here, but it seems I should have taken better account of how big it was
thanks, V. i enjoyed the article. the site is from my home town, making it all that much more enjoyable ! surfer
Anything in particular that you enjoyed about the article Surf? I would love to discuss anything I have posted on this thread -- thats the point Hope all is well with you -- haven't spoken in awhile, Commisso