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From: ellis@chips2.sri.com (Michael Ellis)
Newsgroups: comp.ai,talk.philosophy.misc
Subject: Re: Free will and responsibility.
Keywords: Behaviorism, materialism, dogma, science
Message-ID: <234@unix.SRI.COM>
Date: 19 Jun 89 05:42:33 GMT
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Reply-To: ellis@chips2.sri.com.UUCP (Michael Ellis)
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> Brian Colfer >> Chris Malcolm >>> me

>>>    Lots of "ifs" there. First, and least important, is that the brain
>>>    isn't causally determined because of QM + Chaos theory (either one
>>>    in themselves is not sufficient): Brain state n+1 is provably not
>>>    "determined" by brain state n plus sense data. Also notice you
>>>    neglected to mention "output" or "control data".

>Mike get off the QM (quantum mechanics) thing... according to this reasoning 
>we should consider everything to be non-determined rocks, trees, movement 
>of planets. We can say all sorts of nonsense by evoking mystical forces,
>here QM.  And Chaos theory ... come on ... chaos theory **does** still
>express a causal relationship but just one that is so complex ( too many
>variables ) that we can not predict state N+1 ( where N is just before 
>things become too complex).

    Ultimately, none of that stuff really is determined in the sense that
    you want. And knock off the "mystical forces" crap. Would you prefer I
    accuse you of "closet Theism" to support your 19th century determinism?

    If you are decide to seriously answer this article, please address this
    point: Chaos theory says that minor fluctuations at points of bifurcation
    in suitably complex systems have massive global effects. If those minor
    fluctuations are genuinely random (as in QM, not merely the classical lack
    of knowledge) then the global behavior also is *genuinely* random. Not just
    "too many variables": If we knew *all* the variables and had a computer
    of infinite capacity -- if we were Laplace demons -- we still could not
    predict. 

    If anyone here is being mystical, it is you who refuse to face up to
    modern science. I'll get off this QM thing once you get off this 19th
    century determinism thing. 

>I'm saying that according to QM the brain is **just** as determined as 
>everything else.  If we deal with everything else (but the brain) as if it 
>was determined why not treat the Brain the same way...

    And that's hardly very determined at all.

    What kind of prediction would we get even supposing we had complete
    knowledge and a computer of infinite capacity? If chaos theory
    and QM are correct, we would predict a gigantic number of globally
    divergent possibilities over even a fairly short interval of prediction,
    if the brain is even as complex as a dripping faucet or a rising smoke
    column. (And none of this is to address the truly awful issue of what
    kinds of functions map neurophysiological predicates to mental predicates!)
   
    I *am* treating the brain like anything else. Nothing physical in the
    universe is completely predictable. This doesn't usually matter for 
    phenomena whose attributes we care about are approximated by linear
    differential equations, like most ideal objects in engineering
    books, or, similarly, those artifacts we have consciously designed after
    their example. It is a great testimony to the cleverness of science that
    we have designed things that behave so predictably under the press of
    a button.

    But the brain, like the weather, isn't one of those things.

>Either the brain is *all* physical matter or it isn't ... which do think?
>If it is then the same "laws" applicable to the rest of the universe 
>apply to it also.  If it isn't then you must evoke spirtual metaphysical
>crap. (Flame throwers on..? Let me get my fire suit)

    I'm not into the metaphysics of substance. Let's just say I prefer to
    bracket that question, especially considering how incoherent the notion
    of "material substance" has become this century *in the scientific 
    community*.

    Anyway, even if mind/brain identity theories are correct, we are probably
    in deep trouble where meaningful predictions are concerned.

    To take an example from Fodor: Consider the function that maps physical
    objects to money. Some money is in the form of valuable metal. Other
    is in the form of slips of paper. And then there are electronic blips
    in computers, and so on. Even if all this physical stuff *were* 
    metaphysically deterministic can we ever reasonably expect physical
    theories which predict the motions of all those physical objects to
    tell us anything meaningful about economics? Except for the grossest of
    predictions ("the gold itself will not suddenly transform into some
    other metal"), physics can tell us very little about economics.

    Token theories of mind/brain identity are sort of like that. Just
    what in the brain would correspond to the belief that your car needs
    a valve job or the desire that your lover would stop cracking her 
    knuckles? Even simple beliefs and desires like these almost certainly 
    correspond to a disjunction of an enormous number of radically dissimilar
    brain states (assuming "brain state" even refers to something real). Brain
    states can get us to gross predictions ("thoughts cease when we run
    over this brain with a steamroller"), but it isn't clear that brain state
    talk will ever get us to meaningful predictions about beliefs that are
    any better than folk psychology.

    In other words, brain state language deals with natural kinds that "go
    together"; mind state language deals with yet other natural kinds that
    "go together". Both languages really talk about the same stuff if that
    makes you feel better metaphysically. But the two different languages 
    don't "go together" anymore than physics and economics (sort of like
    a nightmarish version of applying Nelson Goodman's predicate "grue" to
    emeralds). The realms of discourse are autonomous in that even if economics
    is theoretically reducible to physics, the reduction is humanly impossible 
    and unknowable. Throw in what QM+Chaos theory and the reduction may well
    be theoretically impossible as well.

>Are thoughts, beliefs, desires etc. behaviors?

    Not if behavior only counts what is publically observable. There is
    a crucial part of beliefs and desires that you have to be the subject in
    order to know.

    And not if behavior leaves out intentionality: What you are trying to do
    is an intrinsic part of what you are doing even if B.F. Skinner does
    not count it as scientifically important.

    Surely you know what beliefs and desires are. What nobody really knows
    is what they "are made out of" (if indeed, they are made out of anything)
    or "what they are caused by" or "how they are realized in our brains".

>>But what's QM? And why is Chaos in itself insufficient to carry your
>>point? 

    QM is quantum mechanics.

    Without QM, one could still assert that things are *really* deterministic,
    however it is not humanly possible to perform the computations or acquire
    knowledge of all the variables. This is to say, metaphysically we would be
    deterministic, but there would be overwhelming epistemic problems in making
    any prediction.

    With QM, even if you knew *everything*, you could not predict. Quantum
    randomness is "metaphysical" in most viable interpretations. But the ardent
    determinist however, might still sleaze out by asserting that quantum
    randomness operates only at levels so small that it has no macroscopic
    consequences.

    Now chaos theory predicts that microscopic fluctuations at points of
    bifurcation have enormous effects on macroscopic global behavior. This
    is a *hard* prediction of chaos theory. Those who doubt this are urged
    to refer to any text on chaos theory. So Chaos theory + Quantum mechanics
    are both required to assert the metaphysical and epistemic randomness
    of global behavior for suitably complex systems.

-michael

    If quantum mechanics is right, a lot of philosophers are in deep trouble.

-John Searle