Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site pyuxd.UUCP Path: utzoo!watmath!clyde!burl!ulysses!gamma!pyuxww!pyuxd!rlr From: rlr@pyuxd.UUCP (Rich Rosen) Newsgroups: net.philosophy,net.math Subject: Re: Sc--nce Attack (really on minds and computers) Message-ID: <1925@pyuxd.UUCP> Date: Sat, 19-Oct-85 20:39:50 EDT Article-I.D.: pyuxd.1925 Posted: Sat Oct 19 20:39:50 1985 Date-Received: Sun, 20-Oct-85 06:14:24 EDT References: <299@umich.UUCP> <10699@ucbvax.ARPA> <10700@ucbvax.ARPA> <10702@ucbvax.ARPA> Organization: Whatever we're calling ourselves this week Lines: 106 Keywords: Turing machines vs. the mind Xref: watmath net.philosophy:2890 net.math:2395 >>Your points seem to be: >>(1) Humans can recognize consistency of certain formal systems, and >> machines lack this ability . >>(2) There is something mysterious about this ability, and nondeterminism >> has something to do with it; therefore >>(3) no Turing machine can be equivalent to a human mind. >>You are confusing two issues: reasoning *within* a formal system, and >>reasoning *about* a formal system. > [I don't think that is what I am confused about.] [TEDRICK] If you understand what you're confused about, you're not confused about it. > [Yes, this is exactly the point. Exhibit the turing machine that > is claimed to be equivalent to the human mind, and the human mind > can reason about the system in ways impossible within the system. > Thus we contradict the assumption that the machine was equivalent > to the mind.] > OK, we at least have a clear point of disagreement. I don't believe > human beings are deterministic. I also don't accept the laws of > physics as absolute. I accept them as an absolutely brilliant > model but not as complete truth. I don't accept the notion that > the human being is just a very complex machine. The only reasons for doing so would be that you either have some evidence that this is not so, or you simply refuse to believe it because you don't like that conclusion. The first possibility (which I doubt is true) would be reasonable. The second (which is engaged in by a large number of people in this very newsgroup) is fallacious. > I originally asked whether anyone disputed my claim that the human > mind is not equivalent to a turing machine. After all the negative > response, I would like to change my question to: > > *IS THERE ANYONE THAT AGREES WITH ME THAT THE HUMAN MIND IS PROVABLY > NOT EQUIVALENT TO A TURING MACHINE?* I could care less about the exact type of machine that the human mind really is, but I have no disagreement with the notion that the mind and brain are represented as some sort of machine. To throw yet another bone into this mix, I will quote from the oft-misquoted (at least here) John Searle, from his "Minds, Brains, and Programs": I want to try and state some of the general philosophical points implicit in the argument. For clarity I will try to do it in a question and answer fashion, and I begin with that old chestnut of a question: "Could a machine think?" The answer is, obviously, yes. We are precisely such machines. "Yes, but could an artifact, a man-made machine, think?" Assuming it is possible to produce artificially a machine with a nervous system, neurons, axions, and dendrites, and all the rest of it, sufficiently like ours, again the answer to the question seems to be, obviously, yes. If you can exactly duplicate the causes, you could duplicate the effects. And indeed it might be possible to produce consciousness, intentionality, and all the rest of it using some other sorts of chemical principles than those human beings use. [ALL THIS, MIND YOU, FROM A "CRITIC" OF AI!] "OK, but could a digital computer think?" If by "digital computer" we mean anything at all that has a level of description where it can be correctly described as the instantiation of a computer program, then again the answer is, of course, yes, since we are the instantiations of any number of computer programs, and we can think. "But could something think, understand, and so on *solely* in virtue of being a computer with the right sort of program? Could instantiating a program, the right program of course, by itself be a sufficient condition of understanding?" This I think is the right question to ask, though it is usually confused with one of the earlier questions, and the answer to it is no. "Why not?" Because the formal symbol manipulations themselves don't have any intentionality... I think at this point Searle destroys his own argument. By saying that these things have "no intentionality", he is denying the premise made by the person asking the question, that we are talking about "the right program". Moreover, Hofstadter and Dennett both agreed (!!!!) that Searle's argument is flawed. "He merely asserts that some systems have intentionality by virtue of their 'causal powers' and that some don't. Sometimes it seems that the brain is composed of 'the right stuff', but other times it seems to be something else. It is whatever is convenient at the moment." (Sound like any other conversers in this newsgroup?) "Minds exist in brains and may come to exist in programmed machines. If and when such machines come about, their causal powers will derive not from the substances they are made of, *but* *from* *their* *design* *and* *the* *programs* *that* *run* *in* *them*. [ITALICS MINE] And the way we will know they have those causal powers is by talking by them and listening carefully to what they they have to say." Readers of this newsgroup should take note of how a non-presumptive position is built, and of how someone quoted right and left in this newsgroup doesn't even agree halfheartedly with the notions of those quoting him. -- Anything's possible, but only a few things actually happen. Rich Rosen pyuxd!rlr