Paul William Berg

(link to slashdot)

First, as to the argument that it always takes a more advanced mind to understand a lesser one, that is the very (non-intuitive) thing that the law of universal computation disproves. Given a Turing complete set of primitives, anything operation possible can be performed. A trivial example is simply that since all basic x86 primitives can be decomposed into sequences of the "nand" operation, a simple nand gate can be used to build a C++ compiler, and hence the browser you are reading can be not just decomposed into a series of assembly instructions, but indeed into nand itself, certainly a simpler operation than that of the browser currently being used. The book, Structure and Interpretation of Computer Programs has the introductory student write a full Scheme language interpreter in the Scheme language, then an assembly language register machine in the scheme language, and finally a scheme Interpreter in assembly language, then has the language run itself several layers of abstraction deep just to drill this point in... any universal computer can emulate any other universal computer. Since every law of physics is inately calculatable (even if nondeterministic) then the entire universe can be simulated by a universal computer.

The Chinese room thought experiment only addresses weak AI, hence the distinction. First of all, it assumes that symbolic manipulation without understanding of context is even possible. It has now been quite some time since Turing formulated his famous test and no one has come anywhere close to passing it through context free symbolic manipulation. Personally, I think that such a system is either impossible, or more difficult to construct than a truely intelligent system. If such a thing is possible, then I would not consider it intelligent (and many refute the validitiy of the Turing test on this point). He goes on to refute the "brain simulator" saying that the simulator itself does not "understand" the information flowing through it's synapses. I would also say that the brain doesn't understand it's synapses either. A big assumption in this thought experiment is that the thought experimenter himself is somehow more capable than the experiments he his thinking about, where in reality there is scant evidence that the biological system meets the stringent requirements he is demanding of the artificial system.

The symbolic transform mimicing intelligence view of AI is a very naive view, and one rejected by strong AI researchers. Strong AI does not "act intelligent" via a laundry list of scripted rules. Strong AI has to be taught about the problem through experience and devise a solution to it. In the Chinese room experiment, the system cannot learn based on its experience, therefore it is weak AI, not truely intelligent, and the system, if it one the Turing test tomorrow, would be deemed clever, but inferior to most good AI systems already out there. We have reliable systems today that learn basic language and can function on par with lower mammals. We have not yet created intelligence at the levels that we as humans are at, as they do not ponder their own existence, and we are a long way from doing so. We are not, however, very far from the levels of intelligence we observe in cats and dogs.

To revisit the Chinese room. If the Chinese speaker outside the room described, in chinese, a sequence of rules for performing a novel action (a new dance step for the sake of argument) and the room, after replying with questions to clarify finer points about the process, responded with it's ideas on new flourishes to the steps, then THAT would be indicative of intelligence in the system. I do not think the Chinese room addresses this possibility at all as it assumes a much simpler interaction, perhaps preconcieved bias about the possibility of such interaction interfering with the introduction of such a possibility into the experiment. I do not believe this level of interaction is possible with the describes symbolic manipulation, but I do, strongly believe that such an interaction is possible in true AI, and in fact, recent experiments get these types of responses (on a very simple scale) and rely on such responses to ensure that they are NOT simply doing symbolic transformation.

Quantum Physics is calculatable with math.
Physics is calculatale with math.
Chemistry follows the laws of physics and Quantum Physics.
All elementary brain functions, indeed all physical processes in the universes are describable in terms of one of these disciplines.
A universal computer can calculate all three of these disciplines, and in addition, the discipline of mathematics which can describe an infinite variation of these disciplines not even in existance, AND can describe itself.
A universal computer is trivial to construct. You are looking at one now.
Therefore, everything in the universe can be simulated on a universal computer.
Your brain exists in this universe, or at the very least, exists in concordance with a variation of a chemistry, physics and quantum physics calculatable by mathematics. If you deny this, then the brain is not part of this universe, is spiritual in nature, and cannot be reasoned about logically, and this breaks down into a religious argument.
Therefore, the brain can be simulated on a universal computer, as it is a subset of the universe that can be simulated.

This proof does not take into account the disconnect between variations of universal computers. The Von Neuman machine in front of you may very well be a piss poor platform to simulate the workings of an intelligent mind on and highly inefficient, just as it is horrible at doing quantum calculations and may take decades to do what a quantum computer can do in an instant, but it can be done, and, given that we have working examples of physical minds at our disposal to reverse engineer, I'm sure we can come up with a universal computer suitable for such a simulation given the time.

Finally, none of the above requires a deep understanding of the human mind. The human mind is often studied for ideas because, well, it's the only working model we have to reverse engineer. However, since we are not really interested in human minds (they can be created fairly easily with a couple drinks at your local hangout) in this discussion, but rather, human-level intelligence, we are really interested in modeling the outcome, not the low level process. Most all ideas gleaned from human brain research are rapidly decomposed into their pure mathematical function when implemented into strong AI.

His Response:

The book, Structure and Interpretation of Computer Programs has the introductory student write a full Scheme language interpreter in the Scheme language, then an assembly language register machine in the scheme language, and finally a scheme Interpreter in assembly language ....

It's an interesting excercise that I went through as an undergrad (though I switched majors and became a mechanical guy instead of a software guy). I remember Scheme as a pretty fun language to program in, once I sort of got the hang of it, but this is an aside.

any universal computer can emulate any other universal computer.

As this applies to the AI argument, the problem is that you have to assume that the human mind is a type of universal computer, which is a statement disputed by detractors of strong AI. At any rate, it is an assumption that the human mind is software.

The Chinese room thought experiment only addresses weak AI, hence the distinction. First of all, it assumes that symbolic manipulation without understanding of context is even possible.

The Chinese room, actually addressed strong AI -- at least that's what it's intended to disprove, I'm not sure that the experiment says anything about weak AI, other than to say that *all* we can hope for is weak AI.

As to symbolic manipulation without understanding of context, that describes exactly what my computer right now is doing (unless you really want to argue that my laptop *is* a working mind, which I think would be a hard argument to make). That's the crux of the argument; computers don't have context and will never have context. As to the fact that they do (mindlessly and succesfully) manipulate symbols I don't think is arguable.

Turing formulated his famous test and no one has come anywhere close to passing it through context free symbolic manipulation.

A BASIC program running modified and extended versions of the Eliza program *have* passed actual Turing tests. The Turing test I don't think is taken seriously by anyone as a test for strong AI since it's hard to argue that a thousand lines of BASIC is sentient. See:

http://www.nyu.edu/gsas/dept/philo/faculty/block/p apers/msb.html [nyu.edu]

(you have to scroll down a bit where he describes the experiment).

after replying with questions to clarify finer points about the process, responded with it's ideas on new flourishes to the steps, then THAT would be indicative of intelligence in the system.

1st) The question that the Chinese room asks is this: does the person following the rules to shuffle and spit out Chinese characters speak Chinese? The answer is obviously no, as they have no idea what the symbols they're spitting out actually mean. In your example, the person, the person-room system, etc. has no idea whether they're telling a dirty joke, discussing the weather or asking questions about dance moves. That's the actual point -- appearing to understand a languge is not the same as understanding a language (think of it as additionally disproving the Turing test as a valid test for intelligence).

2nd) In the thought experiment, all possible answers to all possible conversations have been pre-programmed by the English rule-book the non-Chinese speaker inside is consulting and following. Would you argue that this is intelligence? Or does it just give the impression of intelligence (and the impression of being able to speak Chinese).

Without having thought much about your "universe inside of a computer" idea, I have to say that at the moment I can think of one thing that does make this impossible: chaos. A computer fed with all the laws of physics would not predict you, your preference in ice cream, McDonald's, human biology, etc. much less contain the human mind.

In fact, maybe chaos is just one example of complexity that can't be modeled with a "simple" universal computer: after all, it's a big assumption to say that the cosmos is just one big universal computer (which I think is exactly what your argument is based on).

My rebuttal:

2 salient points you bring up that I need to comment on.

1) In the thought experiment, all possible answers to all possible conversations have been pre-programmed by the English rule-book the non-Chinese speaker inside is consulting and following.

I would argue this is not only impractical, but impossible in the same vein as the halting problem. Introducing a paradoxical supposition into the thought experiment is bound to give paradoxical results, like multiplying by infinity or dividing by zero. It might make the thought experiment interesting, but conclusions gleaned are invalid without non-paradoxical suppositions. The point is, that without an omnicient-yet-stupid system, this experiment is impossible.

2) it's a big assumption to say that the cosmos is just one big universal computer.

It's not that the universe is a universal computer, but rather, all processes that operate in the universe operate on a finite set of laws (or 1 law maybe if we ever get a GUT) that can be calculated by a universal computer (except perhapse randomness, if it exists, which keeps us from making a mind-predictor, thank goodness :) See below). In fact, all of math, for which the laws of the universe is but a small subset can be calculated on a universal computer. Hence, the entire universe can be calculated on a universal computer (albeit a very large one, likely larger than the universe itself unless we can really make good use of quantum entanglement.) However, it is my educated guess that a human mind probably does not require the resources of the entire universe in order to function, hence a much smaller computer can emulate it. Chaos can be achieved either through pseudorandom means (who's randomness can be scaled to any desired level, depending on how much processing and memory you want to throw at the problem) or, we can cheat and use a source from the real universe, since we happen to have one at our disposal, because we aren't trying to predict human minds with our model... we are just trying to make it work at all.

The crux of the argument, IMO is that symbolic data manipulation is not intelligence. I couldn't agree more. In the same vein, pulsing ionic discharges that cause the release of neurochemicals is not intelligence. Your pulsing neurons are NOT what causes you to comprehend this sentence... those neurons are simply the man in the box. Similarly, the CPU of a computer or the symbolic evaluation function in an interpreter are just the man in the box. These are just small components of the system, and as I said above, a major flaw in the chinese room thought experiment is that simple symbolic manipulation of chinese is sufficient to satisfy the outcome parameters, but it isn't without introducing a paradoxically omnicient set of rules. No set of symbolic tranformation rules is sufficient to have a chinese room that can emulate intelligence with learning and creativity.

However, a set of logical building blocks, such as neurons or simple primitive functions joined, that can self organize at run time to "learn" behaviors and come up with solutions to problems, would meet such a criteria without any, or with very little symbolic scripting. The system, rather than given a rulebook for chinese text transforms, must learn to pattern match text and map text to concepts, learning new concepts when faced with unmatchable text, and so on, and then, after it's proper education, could operate inside that box and speak chinese. I propose that such a system is not only finite (unlike the infite set of rules of the experiment), but feasible. In fact, I submit that this is equivelent to feeding the box snippets of chinese, along with conceptual drawings until the man in the box can carry on a conversation, not because he is manipulating symbols, but rather because he has successfully learned to speak chinese.

Artificial Neural Networks operate on this very principle (as do other methods, but ANN are the most widely known amongst people not in the field). You don't manipulate symbols with (most) NN's, rather you train NN's to map concepts (including temporally, which means mappings are dynamic). What you end up with (in less than trivial NN's... recurrent primarily) is a nondeterministic mess that often will show surprising levels of intelligent behavior.