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Question about free will and determinism

  1. Jun 26, 2003 #1
    can i know what is the problem with free will and determinism because i saw a lot of people in PF aguing/discussing about it. and what is the problem with 'mind and brain'?
    can someone please explain it to me.

    thank you
  2. jcsd
  3. Jun 26, 2003 #2
    i can't really say much about free will, but determinism (which is the belief that if you know the state of the universe at any one time you can know everything that will ever happen) was proved impossible by Q.M. and its Uncertainty Principle.
  4. Jun 26, 2003 #3
    Aside from Maximus over stating the case, nothing is proved, he is right about the universe being indeterminate and why. Stephen Hawking said In "The Universe in a Nutshell" that by useing Feynman's sumover histories method, however the uncertaintiy is cut in half. So now I guess the universe is only semi-inderterminate

    As for mind and brain, some of us think the the mind is completely within and a function our brain and its electrochemical activity.

    Others of us are not sure about that and think the mind is more than just electrochemical activity of a cellular organ; that the mind may include or be included in spirit, heart and/or soul.

    Some speculate our minds are part of or receptor for a greater mind or consciousness that may be the universe itself or God/creator.

    Needless to say it has yet to be resolved or agreed upon. I don't think that it ever will be or can be.
    Last edited: Jun 26, 2003
  5. Jun 26, 2003 #4
    i wonder royce, which one do you believe to be true?
  6. Jun 26, 2003 #5
    Once again it sounds like the two sides of the brain. One equals the "objective observer" = "determinism." The other equals the "subjective participant" = "free will." In which case both aspects come together to creat "the whole."

    As for the brain and the mind, the brain is the physical aspect of the mind, which is the effect of the brain -- "consciousness."
  7. Jun 26, 2003 #6
    I really honestly don't know. I feel or sense that there is more to our minds than just our brains but our brains have so much capacity as I pointed out in the beginning of my thread Mind and Brain(?) that it is certainly possible that that is all there is to Mind.
    I believe in a God/Creator, that we are all part of him, including all that is the universe and that we all are interconnected via him, the spirit. And, that he, God, has not stopped creating nor, once got it going, abandonded us or the universe; that there is pupose and meaning to existence and the universe. But, is this what I sense as being the part of our minds that is beyound our physical brains?
    I don't know.
  8. Jun 26, 2003 #7
    maximus, isn't it merely proved that we can't ever possibly know the exact state of a system? Nothing about the system's own determinism?

    System's own determinism is put to hard test in situations when there are more that one possible outcomes of given interaction while there exists no deciding factor for any of the outcomes.

    Sort of example could be two perfect pins in contact with their tips in force equilibrium. Its very unstable state and there are very many ways how this unstable balance could resolve. But if the causes for 'slip' from unstable state to stable all cancel out, such state would continue until at least some infinitesimal difference in balance appears. Then, extremely small fluctuations of force have capacity to displace extremely vast amounts of energy that would continue to influence zillions of other such unstable balances.
    This is a realm where free will could reside - weak conceptual influence onto unstable balance of states. Its limited free will in mostly deterministic system, which seems apparently to be the case.

    Quantum soup seems prone to face such unstable states for short periods of time until blown away by external influence, and although brain is mostly deterministic machine, during those very short periods of time its conceptual wishes may have influence and become the deciding factor. Given tremendous amount of quantums involved and slowness of brain, its more like statistical trend rather than instant impact. But still, this sort of free will could make wonders, upto a point of influencing outcome of experiments.
  9. Jun 26, 2003 #8
    totoro, the problem with free will and determinism is that they are both equally unprovable and equally unflasfiable.

    Free will is unfalsfiable because any attempt you make to disprove it, could be what you have freely chosen to do, and would thus further validate the belief in Free Will.

    Free will is unprovable, because any attempt you make to prove Free Will could be what you were predestined to do, and would thus further validate the belief in determinism.

    Use the same reasoning about Determinism (which is the idea that all of the future is predestined).

    Side Note: While maximus is correct that current Science invalidates Determinism, Philosophy is not dependent on Scientific findings, as Science is but one branch of Philosophy. So, while those of us (including me) who believe in Science do not believe in determinism, those of us who wish to be truly open-minded to the full scope of Philosophy cannot choose between them.
  10. Jun 26, 2003 #9
    no, i think it is possible (theoretically, of course) to know the entire state of a sytem at one time, if you froze time and looked at every particle in the universe, but from there you cannot make accurate predictions because of the Uncertainty PRinciple.
  11. Jun 27, 2003 #10
    Re: Re: question about free will and determinism

    Well if half the brain is ruled by indeterminism there is no way for us to control it, and we can say that we're stuck at having no "free-will".

    Besides. The only alternative is randomness. And that's not very flattering.
  12. Jun 27, 2003 #11
    Isn't the uncertainty principle invoked because observation is an intrusive thing?


    ...hang on. I've got to think about that now. :)
  13. Jun 27, 2003 #12
    wimms was astute in asking those questions. There is a difference in our ability to know something, and its existence in the first place. The uncertainty principle, from what I've read, comes from the fact that you alter things in observing them. The uncertainty principle, in its purest form, it seems, is a limit on the ability to gain knowledge, on the certainty of our knowledge of the state of things, not on the certainty of the state of things.

    I don't know what some Chinese man in China is doing...I don't know which way he's going, but that doesn't mean that he is not definitely doing anything, and that does not mean that he does not have a definite velocity (in respect to the Earth), just because I don't and can't know. Just the same, just because no one can know a particle's position and velocity, doesn't mean that the world is indeterministic.
  14. Jun 27, 2003 #13
    maximus, you have to clarify your point now. I wasn't completely sure, but now that others also say same thing: HUP states only about uncertainty of knowledge about the system.
    If behaviour of system itself were handicapped by HUP, we'd have to see macroscopic evidence aswell. For eg. I can't imagine conservation laws as absolute then.

    Still, even if HUP isn't inherent property of universe, this doesn't mean that universe is completely determined. It would be determined if there was only one way to go from begin to end. But amount of possible ways increases with entropy. Like byte of 8 bits can encode only one of 256 values, there are 256 values it can encode. There are unimaginable number of legal ways for universe to evolve, and the way it goes isn't necessarily predetermined by previous states. Even if it is 'in principle', its so vastly uncomprehendable that for any imaginable practical purposes its indetermined.
  15. Jun 27, 2003 #14
    You could not observe things without time. Observance is an interaction. Interaction requires time.

    I think that you're misunderstanding scientific knowlegde. HUP is about our ability to know things, not the things we are trying to know.
  16. Jun 27, 2003 #15
    you are right, of course. we are most certainly unable to know the complete state of a system at any one time, what i mean is that even if we did (theoretically, i assure) we still could not then make acurate predictions about the future becuase of probobility and HUP.
  17. Jun 27, 2003 #16
    I thought the most basic problem about free will / determinism was the disscussion on weather they were compatable or not. If they are, then both may be here, if not then which one (or is there another possibility not thought of yet?)

    I believe that they can be compatable.

    If you take it down to a knowledge argument, the only way one can know every possible state of the future is if you are omniscient.

    In order for one to be omniscient, one only has to know all possible states of the future, not neccesarily which of these states will be actualised.

    but even if it is not possible for a human to know every possible state in the future, and there is no God, can it be said that the world is on some level determined?
  18. Jun 28, 2003 #17
    wait, if we somehow knew the state, then WHY we'd need to use probability to predict? I thought we use probabilities BECAUSE we can't know exact state.
    HUP only states that you have to 'trade position for momentum', and you can't have both, measured. But if you knew both, then we have conservation of momentum at least and thus can track the state. We don't know yet how momentum is exactly 'changed into position', but if we knew, what else would be the cause of inability to predict the future?
    Some component of interaction then must behave acausally in principle? If so, then why conservation laws?
  19. Jun 28, 2003 #18
    The Uncertainty principle has nothing to do with knowledge. If a rock exchanges energy with a particle it alters it - and yet the rock doesn't "know" anything more than it did before having "observed". "Observation", in Quantum Mechanics, is merely the exchanging of energy between physical objects (so the person in China would be doing something certain, unless he were in a vacuum, with no other physical objects at all to determine his state (though really, this is just a faulty analogy, as every one of his particles is "observing" the other)).

    P.S. Forgive me if I make a lot of typo's or if I am not as clear as I usually am. My glasses are broken and I'm seeing double (not to mention the pounding headache that almost kept me from the PFs for the second day in a row).
  20. Jun 28, 2003 #19
    Observation is about collecting information. And the very act of collecting information means affecting the very system you are trying to define.

    Therefore the Uncertainly Principle apparently has everything everything to do with knowledge. Of course, it requires a sentient observer in the first place to make sense of that information.
  21. Jun 30, 2003 #20
    See Tiberius' post on Clarification of QM for my rebuttal to this.
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