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Consciousness, Determinism and the Many Worlds view

  1. Oct 8, 2005 #1
    There are a few threads about determinism here and a few about interpretations of quantum mechanics, so I thought I'd start one that combines them.

    Determinism is nicely defined by the Stanford Encyclopedia of Philosophy as:

    Ref: Stanford Encyclopedia

    I think one of the more contentious phrases used in this definition is the term, "natural law" which is explained this way:

    What exactly does "laws of nature" entail? I think its important to first recognize we're not talking about "supernatural laws" when referring to determinism. The point is, are any laws of nature not deterministic? From reading this article, and many others like it, quantum mechanics is always mentioned as a non-deterministic law. Here, the Stanford Encyclopedia mentions it:

    In conclusion, the article does not resolve whether nature is deterministic or not. We can say quantum mechanics is 'deterministic' but that doesn't address a number of issues, namely the random nature of radioactive decay nor why one possible evolution of the Schrödinger equation is observed and another is not. This is also discussed in the article.

    If nature has a 'random' element to it or not however, is less of a concern regarding consciousness for two reasons. There are two more immediate considerations.
    1) At the macroscopic scale, such things as quantum interactions seem to cancel out. Even if they are statistical or random, does that have anything to do with consciousness? Generally this seems to be dismissed as a red herring. Who cares if things are truly random or not at the microscopic scale of an atom? Our brains, the contention is, are governed not by quantum interactions, but by gross interactions between millions or billions of molecules at any given 'switch' junction. So regardless of whether there is any truly random mechanism in the universe, by the time you add up all the large numbers of interactions, the mind is deterministic in the sense that it is not governed by individual molecular interactions, but by enormous numbers of interactions which may be very (exceedingly) slightly chaotic, but far from random.
    2) Even if quantum mechanics provides for a random mechanism, and even if our brain utilizes this mechanism to function, a switch of some type that produces a random outcome is not special enough in any way to explain why consciousness should emerge. One can insert a pseudo-random switch into a computer, so computationalism is not discouraged by an indeterminate or random mechanism.

    If our brains operate on a macroscopic scale where quantum interactions cancel out, and even if it doesn't, even if there are random mechanisms that our brains rely on to function, the idea that the universe is essentially deterministic remains a valid concept with respect to consciousness. Given this perspective on the subject, and only this perspective on the subject, it seems it doesn't matter if the world is deterministic or not.

    Now I still have to add though, that there is one concept regarding QM that still seems to sit on the sidelines waiting to be recognized (though I certainly don't claim to be the only one that recognizes it). Let's assume for one minute that the many worlds theory of quantum mechanics is true. Let's say that for every possible interaction at the molecular level, all possible interactions actually occur and the world splits off into multiple worlds on another dimension. The first point to make is that this theory is completely deterministic in the sense that all possible futures exist as a function of a past event. This is an important point. In the many worlds theory, we have all possible worlds existing at the same time, and the sum of all these worlds is deterministic, not random at all.

    The second point then, and the biggest question of all is that if all these worlds actually exist, why are we only conscious of a single world? Is there a mechanism or law of nature that results in our being aware of only a single world?
     
  2. jcsd
  3. Oct 9, 2005 #2
    "Another exponential process like this could involve sodium-dependent action potentials. It is possible that the entry of a single sodium ion could depolarize the membrane enough to admit more sodium ions, causing more depolarization etc. in a runaway process, producing the action potential as a collapsed macroscopic event."


    http://www.neuroscience.com/manuscripts-1996/1996-011-miller/1996-011-miller.html
     
  4. Oct 9, 2005 #3
    But we ARE conscious of all worlds (at least conscious of all worlds where we exist). I am typing my reply to this thread right now, but if MW is correct then there is another world where I am not typing any reply to this thread. In each of these worlds, and in all other worlds where I exist, I am conscious of the existence of that world. The parallel worlds "communicate" however only at the level at which quantum states remain coherent - lose the coherency and the communication bewteen the worlds is lost. There is no reason to expect our consciousness (a very non-coherent phenomenon) to be able to surmount the barriers between these parallel worlds, any more than we expect any non-coherent phenomenon to surmount the barrier between the worlds.

    MF
     
  5. Oct 9, 2005 #4
    Tournesol

    Tournesol, thanks for the link. I read it through and found it fascinating. Do you think quantum mechanical mechanisms in the brain are generally disregarded or do you think the debate between classical versus quantum mechanical mechanisms in the brain has yet to be decided? That is, do philosophers and scientists still debate the possibility of QM being utilized by the brain or is that generally poo-poo'ed?

    I read an article about the Japanese neutrino detector called Super Kamiokande and heard the photomultiplier tubes were able to detect a single photon emitted when a neutrino interacted with the water. Regarding your quote, if the membrane is able to react to a single sodium ion because of a "runaway process" involving other sodium ions, it seems that membrane is doing something very similar to the photomultiplier tubes in the neutrino detector. I've not heard of this possible QM mechanism in the brain, so thanks for pointing it out.
     
  6. Oct 9, 2005 #5
    Mf

    Movinging finger, thanks for that. Yes, you're absolutely right. Each separate world has an independent and conscious observer unable to interact with any other world.

    I see I didn't explain the punchline very well unfortunately, because that wasn't what I was getting at. I'll try to elaborate as I see now I didn't get the idea out very well.

    Let's forget about the many worlds view for a moment and assume there is only one world. When we talk about a deterministic universe we also must acknowledge there could be QM mechanisms that result in a genuinely random event. Our brains may or may not make use of such a mechanism, and even if they do, could we not simply put similar pseudo-random number generators into a computer in order to perform a similar task? They may not be identical because computers have no way of creating real random numbers, but we could come close and thus with a random number, a computer should be able to perform everything a brain can, assuming a brain is strictly a fancy, biological computer. Random quantum events or random numbers in a computer would have the same affect of simply making the future slightly less predictable. Again, this assuming there is only one world. Would you agree with that?

    Now I want to elaborate on a possible difference between simply having a less than deterministic future because of some random noise and the possiblility of real quantum mechanical interactions in the brain.

    Let's use the Schrödinger's cat experiment. We'll call the box the cat is in Schrödinger's box. The box as you know has the ability to isolate a macroscopic chunk of matter from the universe. What if we put a computer inside this box with its own power supply. A computer is completely deterministic in the classical sense of the word, so I believe one must conclude that if we allow it to operate while inside the box, we can leave it for days, months, even years and it will be in a state which is completely determinate. Also, it won't have the ability to 'branch off' and create multiple universes, or at least if we say it does, if there are branches for quantum mechanical interactions between air molecules bouncing around the box, all those universes will be identical from the perspective of the computer. The air may be in a different state, but the computer won't be. Even if we put in a random number generator, there is no difference because even random number generators in computers are not really random, they are only pseudo-random. The point is I believe the computer will always end up in the same state regardless of how long it is allowed to run, within reason and as long as no quantum mechanical interactions occur that create macroscopic changes to the computer. Computers are immune to quantum mechanical interactions. From the perspective of the computer, there is only 1 world, not many.

    Now put a person in the box and perform the same thought experiment. If a brain is computational, if the only interactions in the brain depend on the interactions of trillions of ions and there are no quantum mechanical interactions that affect the macroscopic function of the brain, then the same result should occur. The person should end up in a deterministic state. But if there are interactions in the brain which depend on QM, then we should see the entire person go into a state of superposition very quickly. From the perspective of the person in the box though, there is only one universe, the one he is in.

    I guess what I'm getting at is, from the perspective of a single universe (ie: not the many worlds view) it doesn't seem as if there's any benefit to having a random mechanism in the brain. Sure the timeline may not be completely deterministic, but I can't see any significant benefit to a random mechanism in the brain nor any significant difference between a computer and a brain. What benefit would a random quantum mechanical event have that a pseudo-random computation wouldn't?

    However, if we consider the possibility that there are many worlds, then it seems there is a significant difference. The observer seems to go into superposition yet be only aware of a single universe, whereas a computer has no ability to do this without a QM mechanism. I realize I'm grasping at something that isn't as tangible as I'd like it to be here. Intuitively it seems to me the many worlds view is unique and says something about the observer and consciousness that other interpretations miss. I wonder if any of this makes sense others.
     
  7. Oct 10, 2005 #6
    Hi TE

    Could be, but on the other hand QM may be 100% deterministic but still unpredictable (eg hidden variables).

    I agree with all that, except I do not believe that quantum randomness or any other kind of randomness is a significant factor in information processing agents, human or otherwise. To my mind the whole world could be 100% deterministic at all levels.

    OK, I follow this I think, but I have to say that I believe in the decoherence explanation of wavefunction collapse – thus Schroedinger’s cat (being a decoherent system) is never in a superimposed “dead and alive” state. (ps the reason why computers are “immune to QM interactions” is the same, because they are macroscopic decoherent systems).

    I understand what you are saying, but I disagree with the initial assumption that a decoherent system (cat, human brain or computer) can remain in a coherent superposition of quantum states.

    I agree that randomness does not bestow any special powers on the brain, but I guess for different reasons. I believe the world operates deterministically (ie the world is ontically deterministic), and any apparent random behaviour is purely because of our subjective perspective (ie the world is epistemically indeterminable).

    If we accept the MW assumption then I speculate it may be the case that information transfer between worlds is possible only in coherent systems (most of which will be microscopic quantum objects), and decoherence (introduced into most systems including the human brain when we go to macroscopic scales) destroys the ability to transfer information between the worlds – this would explain why each conscious agent is aware of only one world.

    MF
     
    Last edited: Oct 10, 2005
  8. Oct 11, 2005 #7
    The age-old-dispute between determninism and free-will is centered on
    the idea of elbow-room or alternative possibilities -- the idea that
    there is more than one thing you can possible do under a given set of circumstances. If determinism is true, this is automatically
    impossible, so what QM indeterminacy might supply is confirmation of the traditional concept of FW.
     
    Last edited: Oct 11, 2005
  9. Oct 11, 2005 #8
    I'd be interested in your reasoning. I suspect there's been quite a bit written on this topic. If you or anyone has a reference that would be best.

    Granted, having a truly random mechanism such as radioactive decay provides an indeterminate future, but I don't think one can say it provides for free will. It only provides for a future which is unknown. Free will and consciousness seem IMHO to require something more than determinate or random mechanisms.

    As a small proof, if for example you ran a computer program which was allegedly conscious and had free will because it incorporated a truly random set of switches, then one could:
    1. Record all switch positions throughout the computer
    2. Replace all random switches with deterministic switches that mimicked the recording
    3. Rerun the program using the deterministic switches.

    The end result would be a computer who's switches duplicated exactly the original 'random computer'. If the original random computer thought it had free will, then this deterministic computer which duplicated exactly everything that random computer did, must also believe it has free will.

    The conclusion then is that simply having a random mechanism is of no real consequence regarding free will. It may actually produce a random future, but it is no better than a deterministic one at producing free will.

    Perhaps I'm getting off track by suggesting there's a difference when considering the MW theory, in fact I'm sure now I've gotten off track. It may highlight slightly better the difference between pseudo-random mechanisms such as are found in computers from truly random mechanisms, but that is a secondary point IMO.

    I feel there must be something other than deterministic or random mechanisms at play. These are "fundamental" laws. They are causal mechanisms in the sense that they act locally and directly on neighboring parts of the universe. They do not create any kind of integrating or large scale affects, they only produce local affects on neighboring bits of the universe. Strangely, there is some speculation, especially within condensed matter physics, that there is something more to it. Robert Laughlin is a Nobel laureate and I believe his opinion is essentially that we're missing something, so to speak. I believe he's suggesting there is some organizational mechanism that operates above and beyond our reductionist views of determinism. Here's what he says:

    Ref: Laughlin
    Note: Laughlin is not commenting on consciousness here, he is referring only to experiments in condensed matter physics that support his claim.

    What exactly those "principals of organization that ... are transcendent" is unknown, but I have to believe they are responsible for consciousness because I feel the reductionist view which says essentially that "A and B interact this way and that's all that happens" is insufficient to support phenomena known to occur such as consciousness and this reductionist view will shortly be proved insufficient.
     
  10. Oct 11, 2005 #9
    Can you explain please how does indeterminacy endow free will?

    If I toss a coin, and then base my decision purely on the outcome of the coin toss (the outcome of the coin toss is to all intents and purposes an indeterministic outcome), does that mean my decision is a free will decision?

    MF
     
  11. Oct 11, 2005 #10
    My reasoning is basically as follows :
    A random outcome can effectively be generated by tossing a coin. Does anyone seriously believe that the equivalent of “coin tossing” goes on in the brain to generate “free will decisions”? If so, can they explain how it is that tossing a coin can endow free will upon the decision-making process?
    If anyone believes that “random events in the brain” bestow any special powers on the brain then I humbly suggest the onus is on that person to substantiate such a claim, rather than for me to refute it.

    I agree completely.

    Again (in the case of free will, whatever that might be) I agree completely .

    If you are suggesting simply that consciousness is an emergent phenomenon then yes I agree.

    Can you please define clearly what you mean by "free will" in the above context?

    Cheers

    MF
     
    Last edited: Oct 11, 2005
  12. Oct 12, 2005 #11
    I have not claimed that indeterminism is a *sufficient* criterion for FW,
    only a necessary one.

    Except that it actually doesn't.

    Why not ? A necessary condition for FW is Alterntaive Possibilities, and
    indeterminism provides that.

    (Considerably) more details here:-

    http://www.geocities.com/peterdjones/det_darwin.html#darwin_vs_buridan
     
  13. Oct 12, 2005 #12
    No (although it does allow for one ingredient of FW, ie Alternative Possibilities). If you base your decisions on an external deterministic
    mechanism, such as followign a script, that isn't FW either. To say
    that FW is based on an indeterministic mechanism does not mean
    any mechanism will do.

    OK.

    http://www.geocities.com/peterdjones/det_darwin.html
     
    Last edited: Oct 12, 2005
  14. Oct 12, 2005 #13
    Thank you.
    In order to understand the logic here, I need to ask some questions, I hope that is OK.
    In the linked article, free will is defined as "the power or ability to perform actions, at least some of which are not brought about necessarily and inevitably by external circumstances".
    May I ask : "external" is being measured relative to..... what? (ie where is the boundary, what is it that is internal, what is it that is external?)

    MF
     
  15. Oct 12, 2005 #14
    Hi Tournesol.
    I have read through this article several times, and I simply cannot find anywhere in the article any suggested mechanism whereby indeterminism endows free will to homo sapiens. The article talks of the "Darwinian model", is this supposed to be the model which explains how free will arises from indeterminism in the brain?
    Thanks
    MF
     
  16. Oct 12, 2005 #15
    The main problem with most “indeterminacy” models of free will decision-making is that introducing indeterminacy arbitrarily into the decision-making process leads not to free will, but to capricious (irrational) behaviour.

    In the Darwinian model (explained in the above link), an attempt is made to remove the capriciousness without destroying the indeterminacy. This is done by having a 2-stage decision-making process. In the first stage a “random idea generator” (hereafter RIG) creates multiple alternate ideas according to an indeterministic process (this is the source of indeterminacy); in the second stage a “sensible idea selector” (hereafter SIS) examines the various alternate ideas created by the prior indeterministic stage, and rationally (and deterministically) selects one of them for action.

    This model may seem at first sight to provide a means of generating free will. There is a random element (the random idea generator) combined with a deterministic element (the sensible idea selector). The model is thus claimed to be both indeterministic and yet not capricious (it makes rational choices). But does it endow free will?

    Well firstly we need to ask whether or not we have eliminated the capriciousness. If the RIG generates too FEW alternate ideas as input to the SIS, then the system will still appear to behave capriciously (the SIS will have insufficient choices for rational action because of the limited number of ideas generated by the RIG, hence overall behaviour will be dictated by the RIG). Therefore the RIG needs to generate a reasonable number of alternate ideas for each decision.

    Secondly we need to ask whether or not we have eliminated determinism. If the RIG generates too MANY alternatives as input to the SIS, then the system’s behaviour will start to be dominated by the SIS, which operates deterministically. Therefore the RIG needs to generate not too many alternates for each decision.

    Can we say whether this model actually provides free will?

    I cannot answer that question without making an assumption on the definition of free will, and that is a notoriously difficult thing to do. (I do not believe the definition of free will given in the link is self-consistent).

    However, what I CAN do is to show how this model applies to "machine" free will.

    Imagine that we have a deterministic computer-based decision making machine. We now add to this machine a “random idea generator” which generates random ideas based on a truly indeterministic process (possibly powered by some quantum-based device). The RIG generates alternate ideas for action, inputs these ideas to the computer, and the computer then decides which of these ideas to turn into action. The computer is performing the role of the SIS.

    IF it is true that the Darwinian model endows free will, THEN it also follows that the machine we have just created also has free will.

    Would you agree?

    If not, why not?

    MF
     
    Last edited: Oct 12, 2005
  17. Oct 12, 2005 #16
    Free will is a feature of consciousness which allows a conscious individual the ability to decide between various courses of action. If consciousness doesn't exist, free will can't exist regardless of determinate or indeterminate mechanisms. The question then is, "Can determinate and indeterminate mechanisms alone provide for consciousness?" A reductionist would say that's all we have available, so the argument centers on which ones are required for free will.

    If one says the reductionist POV is incomplete, then something else is required for consciousness and without it, we have no free will. In this case, determinate and indeterminate mechanisms are insufficient to provide for free will because those mechanisms alone can not provide for consciousness.
     
  18. Oct 12, 2005 #17
    I am open to the possibility of artificial intelligence, so I am open to the
    possibility of artificial FW. (Note that when we want computers to
    be "creative" , we do indeed use real or pseudo- random number generators).
     
  19. Oct 12, 2005 #18
    Sorry, I'm getting that thought experiment (TE) mixed with another. You're right. This TE wasn't intended to prove an indeterminate mechanism is not needed for FW. This thought experiment shows that an indeterminate mechanism is not a prerequisite for consciousness. My mistake.
    From the perspective of a reductionist, consciousness can be explained by deterministic mechanisms and thus to add "free will" some will say an indeterminate mechanism is required while others (compatibalists) may suggest no such mechanism is needed.
     
  20. Oct 15, 2005 #19
    Thank you - but with respect this is not a "definition" of free will, it simply describes one of the features of free will (unless you wish to claim that ALL THERE IS to free will is the ability to consciously decide between various courses of action?)

    MF
     
  21. Oct 15, 2005 #20
    Hi Tournesol, would you say that the machine we have just created above (by combining a deterministic computer with a random idea generator) now has “free will”?
    MF
     
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