----- Original Message ----- From: "Erik Reuter" <[EMAIL PROTECTED]> To: "Brin-L" <[EMAIL PROTECTED]> Sent: Monday, March 11, 2002 6:08 AM Subject: Re: SCOUTED: Science Meets Spirituality, and Wireless Nanotech VR
> On Sun, Mar 10, 2002 at 09:26:51PM -0600, Dan Minette wrote: > > > Before I answer this Eric, let me ask you a question that will help me > > frame an answer. Do you think science is about the Truth or is it a > > means by which we model, predict, and manipulate phenomenon. > > Sniff. Either this is a trap or you must not know my views as well as I > would have guessed. No trap at all. I now know I need to argue from a practical point of view. Let us consider the practicalities of AI. I remember when they were first touted 20 years ago; when LISP was a hot language. Expert systems were come close to replacing various human experts within 5 years. Anyone from a log analyst to radiologist could be replaced by an expert system. Its now 20 years later, and the horizon for such uses of AI appears to be further away than when they were first touted. Yes, there are uses for expert systems, and for neural networks. But, they are far more limited than they were expected to be when computer power was almost a million times as expensive. Second, when computers are used, the algorithms that are used are carefully written, debugged, tested, rewritten, redebugged, retested, etc. In every step there is a designer/designers who is figuring out what went wrong and what has to be fixed. Thus, algorithms seem to be an expression of how carefully a designer thinks, not something that just happens. With real AI, programs would have to be self modifying. This has been touted to be just around the corner, again, for a couple of decades. From what I've heard, the success has been limited to very restricted toy models (a technical term, not inherently derisive). In most cases, the program soon blows up. Third, humans appear to be able to do things that have been proven to not be capable of being reduced to algorithms. Handling self-referential statements is one of these things. I realize that Dennett argues that humans only appear to be able to do this, its just that they have algorithms that search the possibilities until they stumble over them...like a chess playing program. However, it is very curious that humans would have such an algorithm in their heads without being able to access most of the results: since such access would be evolutionarily favored. Fourth, from the time of Bohr's early writings on the implications of QM on biology (in the '30s IIRC), it has been thought that QM renders the predictions of brain states impossible. Even though, as Zimmy pointed out, the neuron is rather large on a quantum scale, it is also very complex (as Zimmy also pointed out.) Thus, quantum effects can rise quite quickly. Indeed, in a post a while back, I showed how on an idealized pool table, quantum chaos takes effect within 1-2 seconds of the positions and momenta of the balls being well established.. Once we saw how computers worked, it was reasonable to suppose that our brains might also work algorithmically. However, the last 50 years of experimentation have not yielded the results expected by the AI enthusiasts. Instead, very serious arguments have been raised against that hypothesis. Practically speaking, while the hypothesis has not been falsified, it doesn't seem to be a leading candidate. > Anyway, I am a pragmatist, and an experimentalist. Truth be damned! :-) As far as I can see, the last 20 years of experimentation shows that the claims for AI are vastly overstated: that if it will work, it will be in a much longer time frame than touted. My practical experience is when someone starts talking about AI solutions, one should count the silverware _very_ carefully before they leave. Dan M.
