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Determinism vs. Free will

  1. May 6, 2003 #1
    It has been argued that determinism is essential for psychology... the 'free' (or self-generated) kind of behaviour does not exist. So.. is our behaviour determined or is it free? How can we chose one over the other? On what basis can you chose one over the other? Are there implications of this question for the science of psychology?
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  3. May 6, 2003 #2
    Our behaviour shows signs of both free will and determinism.
    So the issue is not that these have to be taken as absolute contradiction.
  4. May 6, 2003 #3
    I think it is important to first identify whether we are autonomous agents in a strict unified sense. This is a variation on the question of free will but I think it's important to make the distinction. In my opinion we are not and are instead at the mercy of a collective of potential executive officers each taking turns to issue orders to our body and constantly revising their respective beliefs.
  5. May 6, 2003 #4

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    When I am honest with my logical self, I cannot fathom how we could be anything other than determined without free will.

    Either, the universe obeys set laws, or it does not. If it does not, then it doesn't act. It must obey set laws.

    Either those set laws dictate exactly what happens, or those laws allow for 'chance' (genuine chance, not pretend chance) to play a role in the process. If chance plays a role, then as the small chances add up into the bigger picture, every single thing in the universe ends up being dicated by 'randomness'...the 50 50 chance faced by every single quark as it spins one way or the other, x 60 billion = what I consider randomness. Now the universe does not behave randomly. It is quite apparently very consistent. So the laws dictate exactly what happens.

    That means the universe it deterministic.

    With the last point though, even if the universe did behave on some sort of 'random' level, or the laws interacted with 'chance' in some way..then chance is chance. It is just as much uncontrollable as a determined law is. And so, in a 'chance' universe, free will is still an illusion.
  6. May 6, 2003 #5


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    Well, one way to argue this is that the quarks etc do not form a full system - the small chances and probabilities do not accumulate, as they are not passed on to each other.
  7. May 6, 2003 #6

    Another God

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    How could that be the case though? I mean, under this conception the universe is stil obey laws right? And the laws dictate how things behave. Now if one quark has a 50 50 situation, then whichever way it happens to go, will affect the next interaction it has. It must build up...musn't it?
  8. May 6, 2003 #7
    No. If it has a 50/50 chance then it and every other one has a 50/50 chance every time; like flipping coins. I believe that the randomness and uncertainty at the quantum level go all the way up the ladder to include the whole universe itself. The laws of physics rule and operate within the laws of propability; therefore, we do not live in a deterministic universe. Does this have anything to do with free choice as far as our lives are concerned? I don't thinks so other than making it not physically impossible.
    IMO We as human beings are at least influenced by our genes, the way that we were brought up and the sum total of our experiences and knowlege and our intellegence, wisdom and personallities. When we come to a point were we have to make a choice one way or the other all of those thing plus the present circumstances and our mood at the that time all influence our choice. Not only that but we never have all the information we need to make the best or wisest choice. Having said all of that, I believe that within those limits yes we have free will. We even have the freedom to not decide or toss a coin. The coin BTW that has no memory of the results of the last time it was tossed.
  9. May 6, 2003 #8


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    If I understand correctly, you are saying that, once we accept an element of chance in the microscopic realm, we should expect everything to be "random".

    That is not the case, since you can have (as QM says) well defined probability distributions that "add up" in the larger scales to well defined behaviors.

    A simple example would be a flash light. When you turn it on in front of a wall, there is no way of saying where each individual photon will interact with matter (it may do so scattering from an air molecule, or with the first atom in the wall, or with an atom that is many layers into the wall). However, when you combine that with the fact that your retina will synthesize an image only after having received some million scattered photons, it turns out that your optical nerve will fire for sure after a couple milliseconds; strictly speaking, you may still have an uncertainty of some picoseconds, but the general behavior you will follow will most probably not change due to that tiny difference.

    IOW, there are many instances in which systems behave like a ball in the bottom of a parabolic surface. There are many sources for perturbations that will give tiny kicks to the ball in all directions, but there is a big ammount of information you do know about the ball in general; maybe not the position of all individual atoms (which is random due to thermal motion), but you know that it will stay around the center of the surface.

    Another example that may be useful is your behavior morning, while preparing a cup of coffee. There are zillions of random movements in the boiling water, and yet they can be completely inconsequential for the fact that you will end up at work the same morning.

    Of course, there are also instances in which small changes do induce big macroscopic differences (like in the case of Schrodinger's cat, or the butterfly effect in chaotic systems, or maybe even quantum fluctiations in a neuron sometimes).

    It is not a white/black issue.

    Excellent point.
  10. May 6, 2003 #9
    It seems clear that there is a chain of causality - that each event in our universe occurs, not in a vacuum, but as part of a continuum, and as such, is an "outcome" of all previous events, in a rapidly widening cone stretching back from event x .

    Does this mean that from the moment of the birth of the universe, all things were predetermined? In a sense, it does, but the equation governing something like that would be so huge as to be, for all practical purposes, infinite.

    In terms of the complexity and messiness of our lives, that causal chain is very hard to see, but still, every decision we make, every physical motion, every thought, every word we speak, is also building on and produced by that chain.

    But because that chain is so complex and hard to see, for all practical purposes we may as well think of ourselves as having a "free will."
  11. May 6, 2003 #10


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    i believe we have choices with wide boundaries...
  12. May 6, 2003 #11
    Otherwise, how are they going to rake in all the dough?

    I can, of my "own volition," come over and smack you on the side of the head, if you don't watch out!
  13. May 6, 2003 #12
    Free will is acausal, and therefore illogical. It does not exist.
  14. May 6, 2003 #13
    Are we speaking to a robot here? Or, is it because this is what you "choose" to believe? Of course you can state there is no choice in the matter, but then why do I choose otherwise? If that's not good enough, then who needs to know? And what's the point in answering the stupid question in the first place?
  15. May 6, 2003 #14

    My sister is a psychologist and I once had an insightful conversation with her about this issue. She championed the position of assuming everything involves free will until proven otherwise. I reminded her that this stance has in the past led to psychologists locking up and medicating people with purely physical ailments such as Huntington's disease. She claimed that this was simply the price of progress.

    This kind of dogmatic and at times inhumane stance is what leads to the necessity for outside agencies to examine the fledgling field of psychology itself in my opinion. Because it is a dogmatic stance based largely on culturally acceptable philosophies in the absence of medical evidence, that is where the attention is often being focused today. By definition psychology deals in issues of mental health and illness, a dialectic perspective demanding a well defined metaphysical stance along the classic western lines of idealism or realism.

    These either-or, free will vs determinism views of classical western philosophies have proven too limited for the task. It is not nature vs nurture, nor is it a question of free will vs determinism. These are convenient dividing lines for processing people like so much meat and justifying the use of any means necessary for attaining the implicite and explicite goals of societies. Nature, however, objects and is finally reasserting herself after a hundred years of absurdity.
  16. May 6, 2003 #15
    Just give me the drugs! ... Yeah, once they have you under their control you have no free will.
  17. May 6, 2003 #16


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    Greetings !
    The partially paradoxical nature of that
    statement is humorous indeed.
    Determinism is an abstract concept, not
    a practical one for us. Hence, even if
    free will does not exist we can't
    practicly prove it, I believe.
    Absolute answers to any questions regarding
    reality do not exist. I'd say that observation
    so far (which is all we got) supports the
    absense of free will.
    Through observation (in a "total" sense - all
    our data input).
    All our data input ?
    Yes, if there's no free will the effectivness
    of psychology is partially diminished
    and more effective alternative methods
    are possible.
    That is certainly a very strong point.
    (Though not absolute, of course.)

    Live long and prosper.
  18. May 6, 2003 #17
    The only reason why there's the appearance of no free will, is because society is always dictating what to do. Do you know what else, we don't know how to be ourselves. And, although we may have fooled ourselves into believing otherwise, we're a bunch of "genuine fakes."
  19. May 6, 2003 #18


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    I think that if you're put in a box with
    no windows you'll still want to eat/drink
    and you'll still want to get out. :wink:

    Peace and long life.
  20. May 6, 2003 #19


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    Factually, this is not true (i.e. there is no such causal chain). Quantum mechanics asserts the opposite, that much particle behavior does not have a root cause. QM is the reigning theory of physics. The existence of predetermined outcomes has been disproven by experiment. (See EPR/Bell/Aspect for example.)

    Admittedly this is counterintuitive for most people (you said "It seems clear...") but facts are facts. Our universe allows for the physical existence of free will (assuming that indeterminism is required for free will).
  21. May 6, 2003 #20
    This issue has been argued before. The inevitable conclusions are:

    1) It is impossible to know, and

    2) It doesn't matter.

    Let me explain. It's impossible to know because any action that we take to find out could be determined, or it could be of our own free will. Thus, trying to find proof of free will could just be part of "the plan".

    It doesn't matter because, as point 1 shows, we can never know, and the outcomes are the same.
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