# Is AI possible? **URL:** \ **Category:** Great Debates\ **Created:** [May 13, 2002, 8:29pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885 "2002-05-13T20:29:22Z")\ **Posts on this page:** 20\ **Page:** 7
**Author:** ![JThunder](https://avatars.discourse-cdn.com/v4/letter/j/e95f7d/32.png) [@JThunder](https://boards.straightdope.com/u/JThunder)\ **Post date:** [May 26, 2002, 12:58pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/121 "2002-05-26T12:58:18Z")
I’m trying to answer as many of these objections as time will permit, so I’ll try to focus on some of the major points. (Quite frankly, many of the other points miss the boat completely, as I’ll be touching on briefly.) I especially want to address the following, as I discuss one of Dr. Roger Penrose’s arguments against the feasibility of hard A.I., based on mathematical logic (one of his areas of expertise). > [@](#): > > \*Originally posted by Phoenix Dragon \* > \*\* > > > [@](#): > > > > In fact, hard A.I. requires three assumptions: (1) that the human mind is entirely material in nature, (2) that the method through which it works is understandable by human means, and (3) that it can be feasibly replicated. > > All the solid evidence points to #1 being true, and there is no solid evidence to contradict that. \*\* How did you come to that conclusion? Can you cite any specific experiments which show that the human mind _is_ entirely material in nature? Exactly how would one construct such an experiment? I will not accept experiments which merely demonstrate a material _component_ to the hu man mind. Besides, I believe that there most certainly are scientific reasons to believe in [the existence of a human soul](http://www.unk.edu/student_org/ccc/Assets/Files/GotSoul-Article.pdf). > [@](#): > > **#2 seems odd to me… Why _wouldn’t_ the opperation of the brain be understandable?** It may or may not, but that’s not the point. Before we conclude that hard A.I. is feasible, we need to know that the brain’s operation IS understandable. To say “Well, of course we can understand it!” is premature and a bit arrogant, especially since we are nowhere close to that goal. > [@](#): > > \*\* > #3 seems like the only true difficulty in the way of AI, and it seems to me to be a simple limitation of understanding and technology. \*\* No, it’s more than that, as I’ll explain in a moment. Besides, it’s inadequate to say “Don’t forget that technology is advancing!” (as was stated in an earlier post). Of course technology is advancing, but that doesn’t mean that these challenges are solvable. Vehicular technology is advancing admirably, but does that mean that we’ll be breaking the light barrier? Clearly, that would be a premature conclusion. > [@](#): > > **Again, can you point out any single thing in the (known, material) universe that can not be replicated with sufficient understanding of how it works and sufficent technology?** Okay, you’ve committed two fallacies here. First, you’re asking about the _material_ universe, whereas we have not established that the human mind is purely material. And second, the responsibility would fall on hard A.I. proponents to show that all material things CAN be replicated – after all, they are the ones who are claiming that the human mind is just a fancy machine. Once again, it boils down to burden of evidence. If we don’t know how to do something, and have nothing but vague proposals of how to begin, should we really be saying “Of course it’s possible!” Or would a more cautious scholar say “Maybe, maybe not”? In fact, here’s a challenge for you. Earlier, **lucwarm** argued that “our theoretical model of computing is just a powerful, in principle, as a human mind.” Well then, what of the following problem which Dr. Roger Penrose pointed out? (Once again, I’d like to remind you that Penrose is a materalist, a world-class physicist/mathematician, and a colleague of Stephen Hawking himself.) In brief, Penrose makes use of Godel’s incompleteness theorem, which demonstrates that within a mathematical system, one can have a statement which is clearly _true_, but unprovable from within the system’s set of theorems and axioms. In other words, it is clearly true, but not _algorithmically_ provable. As Penrose said, “It is these insights that cannot be systematized–and indeed, must lie outside _any_ algorithmic action!” By necessity, a Turing machine only allows for algorithmic actions. In other words, no matter how complicated its operations may be, it is ultimately algorithmic in nature. That is true even for a parallel-processing, data-sharing Turing machine (which, as Turing proved, would be more powerful only in terms of speed, rather than capability). So clearly, there are at least some aspects of human intelligence which can not be adequately captured by our mathematical models of computation. > [@](#): > > **Or do you mean feasible in that it may take too much effort to be feasable? If that’s so, that’s not an argument against AI, but an argument about how hard it would be to do.** Correct, but since that’s not the nature of my stance, that point is irrelevant. ---
**Author:** ![lucwarm](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@lucwarm](https://boards.straightdope.com/u/lucwarm)\ **Post date:** [May 26, 2002, 11:19pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/122 "2002-05-26T23:19:46Z")
> [@](#): > > \*Originally posted by JThunder \* > **I’m trying to answer as many of these objections as time will permit, so I’ll try to focus on some of the major points. (Quite frankly, many of the other points miss the boat completely, as I’ll be touching on briefly.)** Oh come on. **erislover** and I crushed your arguments about consciousness/realization/etc. Just concede you lost that point and move on. \*\* > [@](#): > > [an argument against AI based on Godel’s incompleteness thereom] > > \*\* You’re confusing algorithms and formal logic. I could easily construct a computer program that outputs the statement “1=2” But constructing a computer program that validly proves that 1=2 is a whole different kettle of fish. Now, if you constructed a device that (1) only reasoned using valid logic; (2) started with a consistent set of premises; and (3) outputted the results of its reasoning, it is true that Godel’s incompleteness thereom would apply. But why should limitations be imposed on AI devices to which humans are not subject? (1) People (even mathematicians) make mistakes in reasoning all the time; and (2) People hold inconsistent beliefs. (also, people lie!!) Remove these constraints, and your argument crumbles. Oh, and by the way, I ran a few Google searches, and it would appear that Penrose’s arguments have been largely rejected in the scientific community. This is from his entry in an online encyclopedia: > [@](#): > > Sir Roger Penrose (August 8 1931-) English mathematical physicist. > > * * * > > he argues this based on claims that humans can do things outside the power of formal logic systems, such as knowing the truth of unprovable statements, or solving the halting problem. These claims were originally made by the philosopher [John Lucas]? of Merton College, Oxford. > > Most mathematicians consider these claims to be mathematically incorrect. > > * * * > > This argument is also considered flawed by most in the artificial intelligence (AI) community . . . . ---
**Author:** ![Phoenix\_Dragon](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@Phoenix\_Dragon](https://boards.straightdope.com/u/Phoenix_Dragon)\ **Post date:** [May 27, 2002, 5:09am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/123 "2002-05-27T05:09:11Z")
> [@](#): > > \*Originally posted by JThunder \* > > > [@](#): > > > > All the solid evidence points to #1 being true, and there is no solid evidence to contradict that. > > How did you come to that conclusion? Can you cite any specific experiments which show that the human mind _is_ entirely material in nature? Exactly how would one construct such an experiment? I will not accept experiments which merely demonstrate a material _component_ to the hu > man mind. It’s quite obvious that the brain is material (or “in part” if you want to say that). Expiriments have confirmed that you can manipulate the brain in certain ways that reliably result in a certain reaction. Early neural interfaces are already in progress (I believe I mentioned one earlier). The brain seems to work in complete accordance with the principles of science. This all seems to be pretty good evidence that the brain is a material entity in nature. Further, the test you propose (Proving that there is no super-natural element to the brain) is effectively worthless; One can’t prove a negative. However, with all this evidence, I challenge you to find any comparable evidence of a non-material component to brains. And since you want experiments, have you found any experiments that show that the brain has supernatural components? We have evidence of a material brain, and no evidence of supernatural components to it. It seems pretty reasonable to conclude that the brain is material, untill someone can provide evidence to contradict that. > [@](#): > > Besides, I believe that there most certainly are scientific reasons to believe in [the existence of a human soul](http://www.unk.edu/student_org/ccc/Assets/Files/GotSoul-Article.pdf). Not loading for me. Care to summarize? > [@](#): > > It may or may not, but that’s not the point. Before we conclude that hard A.I. is feasible, we need to know that the brain’s operation IS understandable. To say “Well, of course we can understand it!” is premature and a bit arrogant, especially since we are nowhere close to that goal. And again, why wouldn’t it be understandable? Do you know of anything else in the universe that is not understandable? If not, what evidence is there that it could not be understood eventually (Didn’t I already ask this?) > [@](#): > > No, it’s more than that, as I’ll explain in a moment. Besides, it’s inadequate to say “Don’t forget that technology is advancing!” (as was stated in an earlier post). Of course technology is advancing, but that doesn’t mean that these challenges are solvable. Vehicular technology is advancing admirably, but does that mean that we’ll be breaking the light barrier? Clearly, that would be a premature conclusion. And also not a fair comparison. Taking something of mass faster than the speed of light breaks the laws of physics as they’re understood now, while the human brain certainly does not. There seems to be slim chance that FTL travel will be possible, but that’s a far cry from understanding and/or replecating something that seems to fit quite well in the way the universe works. > [@](#): > > Okay, you’ve committed two fallacies here. First, you’re asking about the _material_ universe, whereas we have not established that the human mind is purely material. Untill there is evidence that it has non-material components, it seems perfectly reasonable to assume for now that it is material, as all other objects seem to be. There is no evidence to suggest otherwise, and untill there is, saying that such a non-evident factor should affect this is as reasonable as saying 2+2 might not equal 4, because there might be some sort of extenuating circumstance we can’t understand and have no evidence for that makes it equal 89. > [@](#): > > And second, the responsibility would fall on hard A.I. proponents to show that all material things CAN be replicated – after all, they are the ones who are claiming that the human mind is just a fancy machine. And I would point out, as I had in the part you quoted, that we seem perfectly capable of replicating anything else in the universe, given sufficient technology. Do you have any reason how this would not be the case for the human brain? > [@](#): > > Once again, it boils down to burden of evidence. If we don’t know how to do something, and have nothing but vague proposals of how to begin, should we really be saying “Of course it’s possible!” Or would a more cautious scholar say “Maybe, maybe not”? Except we do have a basic understanding of how it works, and there are already some projects underway and showing development. The evidence so far seems to indicate pretty well that it is possible. > [@](#): > > By necessity, a Turing machine only allows for algorithmic actions. In other words, no matter how complicated its operations may be, it is ultimately algorithmic in nature. That is true even for a parallel-processing, data-sharing Turing machine (which, as Turing proved, would be more powerful only in terms of speed, rather than capability). So clearly, there are at least some aspects of human intelligence which can not be adequately captured by our mathematical models of computation. Sounds a lot like a variation of the earlier description you had that sounded so perfectly spot-on for a human brain. And what lucwarm said, too. Take an example computer. A very good one, say, one with basic algorithms as to how to do a number of simple actions. Further, the computer is capable of updating these algorithms on its own as it senses the results of those actions, so as to perform them better. Eventually, these algorithms would grow as more information is added to them, handling more circumstances. Some additions are ineffective or counter-productive; If the computer senses this, it may try to correct by removing that part, or by adding a new part to cover for the new circumstance. Now then, how does this differ from the way the brain works, appart from scale? > [@](#): > > Correct, but since that’s not the nature of my stance, that point is irrelevant. I was just asking to see if that’s what you were saying. ---
**Author:** ![JThunder](https://avatars.discourse-cdn.com/v4/letter/j/e95f7d/32.png) [@JThunder](https://boards.straightdope.com/u/JThunder)\ **Post date:** [May 31, 2002, 7:56pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/124 "2002-05-31T19:56:33Z")
> [@](#): > > \*Originally posted by Phoenix Dragon \* > \*\*It’s quite obvious that the brain is material (or “in part” if you want to say that). Expiriments have confirmed that you can manipulate the brain in certain ways that reliably result in a certain reaction. … > We have evidence of a material brain, and no evidence of supernatural components to it. It seems pretty reasonable to conclude that the brain is material, untill someone can provide evidence to contradict that. > \*\* **P.D** , don’t forget. I specifically said that experiments which demonstrate a mere material _component_ are unsatisfactory. We are, after all, discussing whether the human mind is purely physical in nature. Moreover, your comments have been about the human _brain_, which is circular reasoning. Nobody denies that the brain is material, so if we assume that mind = brain, then we are begging the question. > [@](#): > > **Not loading for me. Care to summarize?** Please try again, as I suspect that a mere summary would open up unnecessary questions that are already answered in that article. Besides which, I have enough difficulty finding time to address these myriad points, especially since several were covered in earlier postings. One of the main points, however, is the nature of free will. If human beings are merely machines, then how does one explain free will? One does not, after all, blame a tree for falling on one’s car, whereas one could blame a human being for crashing into that same vehicle. (See [http://www.angelfire.com/mn2/tisthammerw/rlgn&phil/soul.html](http://www.angelfire.com/mn2/tisthammerw/rlgn&phil/soul.html) .) > [@](#): > > **And again, why wouldn’t it be understandable? Do you know of anything else in the universe that is not understandable? If not, what evidence is there that it could not be understood eventually (Didn’t I already ask this?)** Yes you did, and I already explained why those questions are irrelevant. (HINT: If you’re going to insist that the human mind can be understood, then it’s not enough to say “Well, tell me why it might not be!” Additionally, if one is to insist that hard A.I. is feasible, then it’s insufficient to say “Well, tell me why it isn’t!”) > [@](#): > > \*\* > And also not a fair comparison. Taking something of mass faster than the speed of light breaks the laws of physics as they’re understood now, while the human brain certainly does not. \*\* I think you’re overstating the case. As shown earlier, free will most certainly does violate the known laws of physics. Moreover, even if set the light barrier aside, the analogy still holds. It’s illogical to say “Vehicular technology is advancing greatly, so eventually we will be able to travel at half the speed of light!” That conclusion is possible, but simply isn’t warranted. Similarly, it’s illogical to say “Computer technology is advancing dramatically, so eventually, we WILL be duplicating real intelligence!” And furthermore, the barriers to true A.I. are more than just technological in nature. Rather, there is the lack of even a basic _model_ of true intelligence. We have achieved some success in pattern recognition and rule-based systems, but that’s nowhere close to a complete model of intelligence. Again, consider Godel’s theorem. How can we count on algorithmic procedures to find the “truth” of a mathematical statement, when Godel’s theorem explicitly proves that such statements can be (a) algorithmically provable, yet (b) clearly true? > [@](#): > > \*\* > Untill there is evidence that it has non-material components, it seems perfectly reasonable to assume for now that it is material, as all other objects seem to be. \*\* Again, I disagree, since we are talking about _intelligence_, a property which other objects don’t have. Ditto for free will, another property which is absent from your run-of-the-mill objects. Besides which, > [@](#): > > \*\* > And I would point out, as I had in the part you quoted, that we seem perfectly capable of replicating anything else in the universe, given sufficient technology. Do you have any reason how this would not be the case for the human brain?\*\* Quite simply, your premise is erroneous in several ways. We can NOT legitimately claim that we can duplicate anything in the universe, given sufficient technology. We would like to believe that, but unless we know what that technology might entail, such a claim is meaningless. It’s like saying, “I can do anything I want, as long as I find a way to do it.” Clearly, that is speculation, not evidence. Second, we are talking about human _intelligence_, not the human brain. Please keep this distinction in mind. The two may or may not be equivalent, but until this is established, please don’t insist that they are. And finally, we’ve already identified key ways in which the human mind – and thus, human intelligence – is unique from regular objects. Hence, the statement “We can build other objects” does not necessarily imply that “Eventually, we can build human intelligence too!” I’ve said it before, and I’ll say it again. Many of the arguments raised in favor of hard A.I. are mere speculation and belief. We’ve just seen several examples of that. For example, the statement “We can build anything we want, if we have the right technology” is belief, not evidence. It sounds good, and it might (_might!_) even be true, but it does not make for a valid argument. Moreover, it is a mere truism, on a par with saying “I can do anything I want, as long as I find a way to do so!” Ho-hum. When you break them down, such statements amount to nothing more that “proof by impassioned assertion.” They sound convincing, but they have no logical power of their own. ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [May 31, 2002, 8:42pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/125 "2002-05-31T20:42:04Z")
Free will and determinism are not necessarily dichotomous. _Compatibilism_ is the idea that they are able to live in harmony. I don’t know if I am or am not a comptatiblist, but I **highly doubt** anyone has ever demonstrated that free will can violate physics, and certainly not in this thread. ---
**Author:** ![lucwarm](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@lucwarm](https://boards.straightdope.com/u/lucwarm)\ **Post date:** [May 31, 2002, 9:55pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/126 "2002-05-31T21:55:31Z")
I think that the “free will” criterion is subject to the same criticism as many other distinctions proposed in this thread. How do you know if an entity has free will or not? The author of the article on souls proposes the following test: > [@](#): > > Right this moment, exercise your free will. Do something, anything at all, that you don’t think nature or anything else could have possibly known you were going to do. Can you do it? I think I can. Now, I could easily construct a device that will perform an action that is totally unpredictible. Does the machine “feel” that it’s making a decision? Who cares. I think Turing would argue that if we can build a machine that behaves _as if_ it has free will (however we decide to test it), that’s all that really matters. ---
**Author:** ![JThunder](https://avatars.discourse-cdn.com/v4/letter/j/e95f7d/32.png) [@JThunder](https://boards.straightdope.com/u/JThunder)\ **Post date:** [June 1, 2002, 3:52am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/127 "2002-06-01T03:52:55Z")
> [@](#): > > \*Originally posted by erislover \* > \*\*Free will and determinism are not necessarily dichotomous. _Compatibilism_ is the idea that they are able to live in harmony. I don’t know if I am or am not a comptatiblist, but I **highly doubt** anyone has ever demonstrated that free will can violate physics, and certainly not in this thread. \*\* It’s not that free will can violate physics _per se_, but that physics can not account for free will. An object whose behavior is determined _exclusively_ by the laws of physics has no free will. To revisit an example I cited earlier, one does not blame a tree for falling onto one’s car, since the tree was merely enslaved to the laws of physics. However, we would blame a human being who trashed that same car, either deliberately or through gross neglect. Why? Because that person had a choice in the matter. That person has free will. If we believe that the “decisions” of human beings are merely the natural consequences of physical laws – laws over which they have NO control – then we have no business blaming them for anything. I happen to believe that the laws of quantum mechanics allow free will to co-exist with the laws of physics, for reasons too complex to discuss right now. However, there must still remain a source for that free will, and materialist explanations can not account for that. ---
**Author:** ![JThunder](https://avatars.discourse-cdn.com/v4/letter/j/e95f7d/32.png) [@JThunder](https://boards.straightdope.com/u/JThunder)\ **Post date:** [June 1, 2002, 4:23am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/128 "2002-06-01T04:23:39Z")
> [@](#): > > \*Originally posted by lucwarm \* > \*\* > > Oh come on. **erislover** and I crushed your arguments about consciousness/realization/etc. Just concede you lost that point and move on.\*\* Balderdash. You are giving yourself way too much credit, for reasons already discussed. \*\* > [@](#): > > You’re confusing algorithms and formal logic. I could easily construct a computer program that outputs the statement “1=2” But constructing a computer program that validly proves that 1=2 is a whole different kettle of fish.\*\* And you’re greatly misrepresenting my claim, and that of Doctor Penrose. Penrose is not talking about _arbitrary_ statements such as “1=2.” He is talking about statements which are _demonstrably_ true, yet unprovable through algorithmic means. That is VASTLY different from the argument that you presented. Additionally, Penrose (and Godel) proved that there are non-axiomatic mathematical statements which are quite obviously true, but inherently unprovable through algorithmic means. And yet, human beings can see that these statements are true. ERGO, in discerning their truth, human intelligence must use some technique which is NON-algorithmic in nature. > [@](#): > > \*\* > But why should limitations be imposed on AI devices to which humans are not subject? (1) People (even mathematicians) make mistakes in reasoning all the time; and (2) People hold inconsistent beliefs. (also, people lie!!)\*\* Ah, but here, you are putting words in my mouth. I never said that AI devices should _never_ make mistakes, and neither did Dr. Penrose. I think that you have either misunderstood or misrepresented Penrose’s argument. In Penrose’s scenario, the problem wasn’t that algorithmic techniques can make mistakes. Rather, the problem is that algorithmic techniques are _inherently_ incapable of determining the truth of these statements. Obviously, this is quite different from merely complaining that computers might make some mistakes here and there. And BTW, I’m fully aware that there are scientists who reject Penrose’s conclusions. However, I have yet to read ANY seasoned argument against them. Every complaint that I have read involves tangential claims like “But neural networks can do great things!” or misrepresentation of his argument, as evidenced by the reviews of his book on [Amazon.com](http://Amazon.com). ---
**Author:** ![Phoenix\_Dragon](https://avatars.discourse-cdn.com/v4/letter/p/65b543/32.png) [@Phoenix\_Dragon](https://boards.straightdope.com/u/Phoenix_Dragon)\ **Post date:** [June 1, 2002, 4:36am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/129 "2002-06-01T04:36:53Z")
> [@](#): > > \*Originally posted by JThunder \* > \*\ ***P.D** , don’t forget. I specifically said that experiments which demonstrate a mere material _component_ are unsatisfactory. We are, after all, discussing whether the human mind is purely physical in nature. > > Moreover, your comments have been about the human _brain_, which is circular reasoning. Nobody denies that the brain is material, so if we assume that mind = brain, then we are begging the question.\*\* _sigh_ Okay. So nobody denies that the brain is material. What solid evidence do you have that the mind is seperate from the brain and/or that there is a supernatural component? Can _you_ perform some experiment that proves this? If there isn’t any evidence for it, how can you expect others to believe your argument? As for the bits you have mentioned, I’ll get to them now: > [@](#): > > **Please try again, as I suspect that a mere summary would open up unnecessary questions that are already answered in that article. Besides which, I have enough difficulty finding time to address these myriad points, especially since several were covered in earlier postings.** Okay, now it loads… And I really can’t believe THAT is the best support for it (Or actually, I guess I can…). It doesn’t follow reason very well, at all. The argument that without a soul, people could not be the same person after a few years is simply absurd. Things change over time, that doesn’t mean they’re someone else. They’re the same person still. Different, but still the same person. Hell, I’ve changed out almost every single part in my computer but it’s still _my computer_. If that article were right, shouldn’t it be something else now (I have no clue what. Maybe a toaster :rolleyes: )? Then they go into conciousness. Basically, he says that conciousness must exist because we don’t know what it’s like to be a bat. Even with “full physiological information” of bats. Well, that seems about as absurd. Nobody contests that a computer is wholy material and physical, but I doubt you know exactly what it would be like to be a mainframe running a few dozen different programs, do you? And a brain is a good deal more complex that “simple” programs like that, so you should even have an easier time with it. And then, of course, free will. The second article you linked to states that the reason free will must exist is because humans can start their own causal chains… But that isn’t entirely true, is it? People choose what to do based on input. Like right now; I’m not going to go typing this whole thread for absolutely no reason, am I? No, I’m typing it in responce to what you posted. Sometimes it gets incredibly complex; Something happening in one’s life creates a memory, which later starts one thinking about something similar, slowly adding or changing bits and pieces by what seems “right”, untill eventually a full-blown story is formed. “Free will” seems to simply be the ability to reason from input and select a good action based upon that. The human mind, being very complex, makes this a VERY deep process, much more complicated than current computers, as an example. The human mind chooses what it feels is the best option _from experience_, but not necesarily what _is_, absolutely, the best option. Then there were “near death experiences.” I seem to recall that most of these were already debunked, and in any case, the examples given were incredibly vague; I’d appretiate some examples of what was said and done, rather than an opinion (from a rather biased source, I may add) that they were fully detailed. However, it’s already recognized that people will, sometimes, percieve things while sleeping, even if it’s very fuzzy perception, or not even conciously recognized (Like whispering into someone’s ear when they’re sleeping). The same thing is believed to occur occasionally for coma victims, where they don’t conciously percieve something, but their natural body functions do, and they wake up with a (usually rather distant) memory of it. This would be the most “fuzziest” part, since there’s no evidence for or against, except for the statements from people who are unconcious, likely having some sort of shock to the nervous system, possibly with reduced blood-flow to the brain (Common effect of shock, right?), and already in a traumatic experience. In any case, proving or disproving a soul (Which isn’t something I’m arguing against, mind you, despite the poor reasoning I see in that article) doesn’t prove or disprove anything in regard to this thread, IE, is intelligence material in nature. And the comparison of a tree falling on a car and a person hitting a car is also flawed. I doubt you’d blame a person if some external factor made a person fall on a car, either (Like, being pushed by someone else). The reason a human would be at fault for hitting a car is because a human can make choices based on what it feels is the right thing to do. But a tree falling on a car is no more of a “choice” than a human being pushed onto a car. > [@](#): > > **Yes you did, and I already explained why those questions are irrelevant. (HINT: If you’re going to insist that the human mind can be understood, then it’s not enough to say “Well, tell me why it might not be!” Additionally, if one is to insist that hard A.I. is feasible, then it’s insufficient to say “Well, tell me why it isn’t!”)** So are you saying you don’t have any reason why the human mind can’t be understood, or just that you aren’t going to present it? Humans are making large leaps foreward in understanding how the brain works, and it seems to have strong momentum to keep doing so. So with significant parts of the brain understood, more of it quickly being understood, what reason can you present as to why it can’t be understood? Again, it strikes me the same as that whole 2+2 example I gave. If there is no solid reason to believe so, don’t expect a lot of people to buy into it. > [@](#): > > **I think you’re overstating the case. As shown earlier, free will most certainly does violate the known laws of physics.** You contend it does, but it doesn’t have to. Free will is the ability to make choices; My computer can make choices. The human brain simply does this on a much more complex level (That is, if you’re going by the scientific reasoning of how the brain works; And without evidence for something else, it seems the most reasonable explanation). > [@](#): > > **Moreover, even if set the light barrier aside, the analogy still holds. It’s illogical to say “Vehicular technology is advancing greatly, so eventually we will be able to travel at half the speed of light!” That conclusion is possible, but simply isn’t warranted.** Ammusing that you take something that is completely possible (Probably even with MODERN technology). Feasability is certainly an issue, since it wouldn’t be too effective if it took three hundred years to accelerate to that speed, but certainly possible. Especially with some of the long-endurance engines under development. So yes, traveling at that speed is completely possible, feasability asside. Kind of like how you could build a structure two miles tall, but it would require so much of an effort it would be rather infeasable to do so. > [@](#): > > **And furthermore, the barriers to true A.I. are more than just technological in nature. Rather, there is the lack of even a basic _model_ of true intelligence. We have achieved some success in pattern recognition and rule-based systems, but that’s nowhere close to a complete model of intelligence.** But the understanding of it is continuing to advance, and the construction of neural-net computers shows at least a basic model of intelligence (That is, learning ability, even if it’s fairly crude at the moment). It is incomplete, yes, but we’re learning more about it every day. > [@](#): > > **Again, consider Godel’s theorem. How can we count on algorithmic procedures to find the “truth” of a mathematical statement, when Godel’s theorem explicitly proves that such statements can be (a) algorithmically provable, yet (b) clearly true?** The same way we do. Some would contest that 1+1 can not be proven to equal 2. Yet we all know it does. So does my computer. So effectively, my computer already gets past Godel’s theorem in this case. Of course, I’ve only heard what seems like a rather simplified version of Godel’s theorem (Searching on the web only turned in a lot of results that just seem ill-reasoned, and didn’t help out much), so if you’d care to explain -how- this argues against a computer intelligence, please do. > [@](#): > > **Again, I disagree, since we are talking about _intelligence_, a property which other objects don’t have. Ditto for free will, another property which is absent from your run-of-the-mill objects.** Regardless, it is still reasonable, without any _evidence_ in support of non-material components to the human mind, to conclude that the human mind is material in nature. Again, evidence to the contrary is welcome. > [@](#): > > **Second, we are talking about human _intelligence_, not the human brain. Please keep this distinction in mind. The two may or may not be equivalent, but until this is established, please don’t insist that they are.** Why? What evidence is there that the two are seperate (Or, indeed, that the mind even exists seperate of the brain)? > [@](#): > > **"We can build anything we want, if we have the right technology" is belief, not evidence.** Now you’re misrepresenting what I said. I said that we could reproduce anything we know, given sufficient technology. Might not be too feasable, but possible. Unless you have an example of something that might not be possible? Remember when you do that “impossible” does not mean “insanely hard to do”. Basically, you’re whole argument says that AI should be impossible, because of a number of factors, with no evidence to support these factors (Many of which may not exist, or at least, not the way you portray them), and yet I’m being unreasonable by not accepting these without question? And even more, that they counter what evidence that _is_ present to support the possibility of AI? I’m not even arguing about the existance or lack of existance of souls, but the evidence seems to favor that, regardless of their existance or lack of existance, the human brain opperates entirely inside the laws of physics, and that there isn’t an mind seperate of the brain. ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [June 1, 2002, 5:06am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/130 "2002-06-01T05:06:38Z")
> [@](#): > > And yet, human beings can see that these statements are true. 😕 I missed this part. From what I remember of Penrose, he required that consciousness and will involved collapsing of wave functions in some manner that wasn’t clearly defined. In his book, Emperor’s New Mind he went to great lengths to challenge strong AI but didn’t seem to offer any other suggestions. It is not certain, IMO, that humans have somehow solved the halting problem which should be logically impossible. Hell, I can make a program that will always terminate in a finite number of steps and give some answer, whether or not that answer is correct. It is also not clear to me that incompleteness theorems demonstrate that intelligence is not algorithmic in nature. Who is saying that intelligent systems must be complete, or consistent, or able to solve all problems? That seems rather unfair since we cannot do it ourselves. > [@](#): > > If we believe that the “decisions” of human beings are merely the natural consequences of physical laws – laws over which they have NO control – then we have no business blaming them for anything. I don’t see why not. It doesn’t seem important to me whether or not you had a choice in the matter of killing a person or smashing into a car. But I don’t know that we need to get into free will debates here, do we? Or is non-deterministic free will necessary for intelligence? > [@](#): > > _From Emperor’s New Mind, discussing the Strong AI view that any algorithm is intelligent_ > The viewpoint is that it is simply the logical structure of the algorithm that is significant for the ‘mental state’ it is supposed to represent, the particular physical embodiment of that algorithm being entirely irrelevant. As Seare points out, this actually entails a form of ‘dualism’. _Dualism_ is a philosophical viewpoint espoused by highly influential seventeenth century philosopher and mathematician Rene Decartes, and it asserts that there are two seperate kinds of substance: ‘mind-stuff’ and ordinary matter. Hogwash, says I, and Penrose proceeds to bring up the view of universals called ‘Platonism’ (also known as ‘Transcendental Realism’). Though I am very pleased to discuss the nature and ontological implications of different views on the subject of universals, there is no requirement that believing that algorithms are intelligence necessarily implies a form of dualism. If we accept, instead of Platonic Realism, Immanent Realism, then we are under no obligation to abandon a completely materialistic view of intelligence, and rightly so (IMO). Intelligence is a physical phenomenon, IMO, and as an immanent realist I feel that all universal properties, if they exist at all, must exist _only_ “in” things; in other words, if intelligence exists, and multiple things can have intelligence, then intelligence only exists in things. Specifically, for the argument at hand, any algorithmic thing is intelligent in some capacity. Now, I don’t propose to speak for the entire AI community in any respect, but Penrose isn’t digging all the way down IMO. That book was a great read, though. ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [June 1, 2002, 5:20am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/131 "2002-06-01T05:20:41Z")
Just wanted to link the universals debate I started some time ago. It was very interesting, IMO, though it got a little heated in the end (over whether or not color is real! lol) [The Problem of Universals](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=102884) ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [June 1, 2002, 5:23am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/132 "2002-06-01T05:23:41Z")
☹ Much of that thread got eaten in the Great Board Hack… it used to be three pages! Damn it all… ---
**Author:** ![lucwarm](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@lucwarm](https://boards.straightdope.com/u/lucwarm)\ **Post date:** [June 1, 2002, 7:26am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/133 "2002-06-01T07:26:51Z")
> [@](#): > > _Originally posted by JThunder \* > \*\* > Balderdash. You are giving yourself way too much credit, for reasons already discussed._\* Among other things, I described a way that a device could pass the “self-recognition” test you proposed. As far as I can tell, you didn’t bother to respond. \*\* > [@](#): > > And you’re greatly misrepresenting my claim, and that of Doctor Penrose. Penrose is not talking about _arbitrary_ statements such as “1=2.” He is talking about statements which are _demonstrably_ true, yet unprovable through algorithmic means. That is VASTLY different from the argument that you presented. \*\* I used “1=2” as an example to demonstrate that there is a distinction between the output of a device and the result of formal logic. This example shows that algorithmic processes can give outputs that are not only unprovable, but actually false! But if you think I somehow “cooked the books” by choosing this example, why don’t you come up with an example of something that is truly “_demonstrably_ true, yet unprovable through algorithmic means” and we’ll discuss it. > [@](#): > > \*\*Additionally, Penrose (and Godel) proved that there are non-axiomatic mathematical statements which are quite obviously true, but inherently unprovable through algorithmic means. And yet, human beings can see that these statements are true. ERGO, in discerning their truth, human intelligence must use some technique which is NON-algorithmic in nature. \*\* Well, why don’t you give me an example of a statement you can see is true but is inherently unprovable. I’ll try to think of a way that an AI device could output that statement. > [@](#): > > **Ah, but here, you are putting words in my mouth. I never said that AI devices should _never_ make mistakes, and neither did Dr. Penrose. I think that you have either misunderstood or misrepresented Penrose’s argument.** Well, you’re relying on a mathematical theroem - Godel’s thereom. Godel’s thereom applies only if a certain set of assumptions is true. If you agree that some of those assumptions do not hold, then the thereom does not apply. Obviously, you cannot avoid this problem by leaving the assumptions unstated and, when somebody raises the problem, accuse them of putting words in your mouth. \*\* > [@](#): > > In Penrose’s scenario, the problem wasn’t that algorithmic techniques can make mistakes. Rather, the problem is that algorithmic techniques are _inherently_ incapable of determining the truth of these statements. Obviously, this is quite different from merely complaining that computers might make some mistakes here and there. > \*\* Ummm, I’m not “complaining that computers might make some mistakes here and there.” I’m complaining that _humans_ make mistakes (and hold inconsistent beliefs), and therefore by arguing that Godel’s thereom applies to computers, you are implicitly holding computers to a more difficult standard than humans. A computer that made mistakes, held inconsistent beliefs (and lied) would not be subject to Godel’s thereom any more than humans are. If you disagree, then why don’t you tell me a statement that is true but unprovable, and I’ll try to show you how an unconstrained AI device could output that statement. \*\* > [@](#): > > And BTW, I’m fully aware that there are scientists who reject Penrose’s conclusions. \*\* Well, apparently it’s more than a few scientists. It’s the majority of the scientific community. Note that the only reason I inserted this “argument from authority” is that you spent some effort building up Penrose’s qualifications. ---
**Author:** ![lucwarm](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@lucwarm](https://boards.straightdope.com/u/lucwarm)\ **Post date:** [June 1, 2002, 7:58am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/134 "2002-06-01T07:58:37Z")
> [@](#): > > \*Originally posted by erislover \* > \*\* > > It is not certain, IMO, that humans have somehow solved the halting problem which should be logically impossible. \*\* I agree. IMHO, humans tend to optimistically hope that there are simple solutions to complicated problems. This is true in some cases, but not always. If you consider Lewis Carroll’s famous “pork chop problem” for a few minutes, it becomes obvious that there are very strict limits on human “insight.” Similarly, we can imagine a halting problem with 100,000 lines of code, full of interconnecting loops, gotos, and if then statements. 1000s of variables all interracting in 1000s of ways. If there is no elegant way of simplifying the problem, then our only hope is to trace out the program’s steps for a while and see if it loops returns to some previous state. And of course such an approach is not guaranteed to work. \*\* > [@](#): > > Hell, I can make a program that will always terminate in a finite number of steps and give some answer, whether or not that answer is correct. > \*\* Agree. ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [June 1, 2002, 11:44pm UTC](https://boards.straightdope.com/t/is-ai-possible/108885/135 "2002-06-01T23:44:06Z")
Um. Pork chop problem? ---
**Author:** ![lucwarm](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@lucwarm](https://boards.straightdope.com/u/lucwarm)\ **Post date:** [June 2, 2002, 12:25am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/136 "2002-06-02T00:25:37Z")
> [@](#): > > \*Originally posted by erislover \* > \*\*Um. > > Pork chop problem? \*\* Ok, what conclusion is consistent with and demanded by the following statements: > [@](#): > > 1. A logician, who eats pork-chops for supper, will probably lose money; > > 2. A young man always gets up at 5 a.m., unless he has lost money; > > 3. No earnest man, who does not eat pork-chops for supper, need take to cab-driving, unless he gambles; > > 4. A logician, who is in danger of losing money, had better take to cab-driving; > > 5. A gambler, whose appetite is not ravenous, will probably lose money; > > 6. A man who is depressed, having lost money and being likely to lose more, always rises at 5 a.m. > > 7. A man, who neither gambles nor eats pork-chops for supper, is sure to have a ravenous appetite; > > 8. A lively man, who goes to bed before 4 a.m., had better take to cab driving; > > 9. A man with a ravenous appetite, who has not lost money and does not rise at 5 a.m., always eats pork-chops for supper; > > 10. An earnest gambler, who is depressed though he has not been losing money, is in no danger of losing any; > > 11. A man, who does not gamble, and whose appetite is not ravenous, is always lively; > > 12. A lively logician, who is really in earnest, is in no danger of losing money; > > 13. A man with a ravenous appetite has no need to take cab driving, so long as he is really in earnest; > > 14. A gambler, who is depressed though in no danger of losing money, sits up till 4 a.m. > > 15. A man, who has lost money and does not eat pork-chops for supper, had better take to cab-driving, unless he gets up at 5 a.m. > > 16. A gambler, who goes to bed before 4 a.m., need not take to cab-driving, unless he has a ravenous appetite; > > 17. An old man, who does not gamble, and who has not lost money though he is in danger of doing so, always eats pork-chops for supper; > > 18. A man with a ravenous appetite, who is depressed though in no danger of losing money, is sure to be a gambler. Have fun!! ---
**Author:** ![TVAA](https://avatars.discourse-cdn.com/v4/letter/t/c57346/32.png) [@TVAA](https://boards.straightdope.com/u/TVAA)\ **Post date:** [June 2, 2002, 12:40am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/137 "2002-06-02T00:40:31Z")
[The Wrath of the Swarm]: “AI? I’ve yet to see _natural_ intelligence on this world.” ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [June 2, 2002, 6:40am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/138 "2002-06-02T06:40:00Z")
Better late to a thread than never. Did anyone ever get around to defining intelligence? Or at least attempting to define the prerequisites of consciousness? The Turing test, as presented, seems specious … I can’t tell the difference between a diamond and a cubic zirconium … are they the same? But “behavior” can be used to _probe_ the internal world of how a thinking machine operates … and that is a whole kettle of fish of another color! I like Steven Pinker’s stabs at definitions in “How the Mind Works”: > [@](#): > > Intelligence, then, is the ability to attain goals in the face of obstacles by means of decisions based on rational (truth-obeying) rules. … We have _desires_, and we pursue them using _beliefs_, which, when all goes well, are at least approximately or probabilistically true. He goes on to point out the differrent meaning of the word “consciousness”: > [@](#): > > One is _self-knowledge_ … Consciousness is typically defined as “building an internal model of the world that contains the self” … Self-knowledge, including the abilty to use a mirror, is no more mysterious than any other topic in learning and memory. If I have a mental database for people, what’s to prevent it from containing an entry for myself? > > … > > A second sense is _access to information._ … the mass of information processing in the nervous system falls into two pools. One pool … can be accessed by the systems underlying verbal reports, rational thought, and deliberate decision making. The other pool, which includes autonomic (gut-level) responses … cannot be accessed by those systems. > > … > > Finally, we come to the most interesting sense of all, _sentience_: subjective experience, phenomenal awareness … > It seems to be an extra quality of some kinds of information access. What we do need is a theory of how the subjective qualities of sentience emerge out of mere information access… > At least for now we have no scientific purchase on the special extra ingredient that gives rise to sentience. Others are less pessimistic in the ability to define how sentience emerges out of information acccess. Hofstadter, in his famous GEB, takes the view that a self-symbol (see Pinker’s consciousness meaning #1) evolves into a _self-subsystem_ and discusses how various cognitive subsystems report to it and how it interacts with the outside world. > [@](#): > > A very important side-effect of the _self_-subsystem is that it can play the role of “soul” He goes on to suggest that consciousness (in that sentient sense, meaning #3 of Pinker) is an emergent result of self-referential feedback loops: > [@](#): > > My belief is that the explanation of “emergent” phenomena in our brains - for instance … consciousness and free will - are based on a kind of Strange Loop, an interaction between levels in which the top level reaches back down towards the bottom level and influences it, while at the same time being itself determined by the bottom level. In other words, a self-reinforcing “resonance” between different levels. (Sadly, he does not credit the huge body of work by Steven Grossberg on Adaptive Resonance Theory, a neural network system which proposed much the same thing, along with much else) Varela and Churchill (see the “Self - an urban legend?” thread for references and links) also propose the that the loopiness of the system is the origin of sentient consciousness. If this line of thinking is valid, then consciousness can, in fact, be quantified by measuring the degree to which a dynamic informational system is self entagled in these “Strange Loops.” This does not, however, imply that such a consciousness is at all understandable to ours, any more than we can understand what it is like to think like a dolphin. Intelligence and consciousness may be present in a thinking machine, without being very human-like. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [June 2, 2002, 7:10am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/139 "2002-06-02T07:10:05Z")
Here’s the links: [The “Self” thread.](http://boards.straightdope.com/sdmb/showthread.php?threadid=117034) [Churchill’s article in Science: “Self-Representation in Nervous Systems”](http://http://www.sciencemag.org/cgi/content/full/296/5566/308) (You can get the abstract for free, the article needs a subscription or payment, I’ve pasted in some pertinent bits in the “Self” thread.) [And an article on “self” and “consciousness” by Varela](http://www.edge.org/documents/ThirdCulture/t-Ch.12.html) My point with Pinker’s defintion of intelligence is that with such a definition intelligent machines do exist, even if their domains of intelligence is not the same or as large as humans. (Similar to whales who keep track of thousands of individual creatures and objects in huge volumes of ocean in order to accomplish tasks of salience to them, according to rational rules, and whose intelligence we can’t understand) To define intelligence as what we do that others cannot do is arrogant and self-serving. “Creativity” is another thing altogether, the application of a pattern from one intelligence domain (or subsystem) into another (novel) data set with a surprisingly good fit, as one means of accomplishing goals. I don’t know of any AI that models this in any rigorous fashoin … Napster for AI algorithms? ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [June 2, 2002, 7:22am UTC](https://boards.straightdope.com/t/is-ai-possible/108885/140 "2002-06-02T07:22:58Z")
I see that my Science link doesn’t work, so here is the abstract and snippets as placed in the other thread: > [@](#): > > Self-Representation in Nervous Systems > Patricia S. Churchland\* > The brain’s earliest self-representational capacities arose as evolution found neural network solutions for coordinating and regulating inner-body signals, thereby improving behavioral strategies. Additional flexibility in organizing coherent behavioral options emerges from neural models that represent some of the brain’s inner states as states of its body, while representing other signals as perceptions of the external world. Brains manipulate inner models to predict the distinct consequences in the external world of distinct behavioral options. The self thus turns out to be identifiable not with a nonphysical soul, but rather with a set of representational capacities of the physical brain > \ > > Descartes proposed that the self is not identical with one’s body, or indeed, with any physical thing. Instead, he famously concluded that the essential self–the self one means when one thinks, “I exist”–is a nonphysical, conscious thing. At this stage of scientific development, the Cartesian approach is unsatisfactory for three reasons: (i) psychological functions generally, including conscious thoughts such as “I exist,” are activities of the physical brain (1, 2); (ii) aspects of self-regulation (e.g., inhibiting sexual inclinations), and self-cognition (e.g., knowing where I stand in my clan’s dominance hierarchy), may be nonconscious (3); and (iii) as the Scottish philosopher David Hume (1711-1776) realized, there is in any case no introspective experience of the “self” as a distinct thing apart from the body (4). Introspection, Hume concluded, reveals only a continuously changing flux of visual perceptions, sounds, smells, emotions, memories, thoughts, feelings of fatigue, and so forth. > > … > > This remarkably diverse range of uses of the self-concept motivates recasting problems about “the self” in terms of self-representational capacities of the brain. Doing so deflates the temptation to think of the self as a singular entity and encourages the idea that self-representing involves a plurality of functions, each having a range of shades, levels, and degrees. Further, it broadens the inquiry beyond humans to other species, suggesting that varying levels of coherencing operate in all nervous systems of any significant complexity. The reformulation also sets the stage for designing experiments to determine more precisely the types of self-representations nervous systems have, how they are connected to one another, and the nature of their neural substrates (6). > > … > > Self-representations may be widely distributed across brain structures, coordinated only on an “as-needed” basis, and arranged in a loose and loopy hierarchy. > > … > > The most fundamental of the self-representational capacities probably arose as evolution stumbled on solutions for coordinating inner-body signals to generate survival-appropriate inner regulation. > … > > An appealing hypothesis defended by Damasio (12) is that the self/nonself distinction, though originally designed to support coherencing, is ultimately responsible for consciousness. According to this view, a brain whose wiring enables it to distinguish between inner-world representations and outer-world representations and to build a meta-representational model of the relation between outer and inner entities is a brain enjoying some degree of consciousness. … On this hypothesis, the degrees or levels of conscious awareness are upgraded in tandem with the self-representational upgrades. [Previous page](https://boards.straightdope.com/t/is-ai-possible/108885.md?page=6) [Next page](https://boards.straightdope.com/t/is-ai-possible/108885.md?page=8)