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Determinism and Free will

  1. Jan 16, 2012 #1
    As of late i have been musing upon the nature of free will. However i disagree with the standard interpretation of the link between Determinism and free will. Incompatibilism states that Free Will and Determinism cannot co-exist, and i agree with this stance. Where i disagree is with the empirical nature of our reality and the implications for free will.

    Quantum mechanics has demonstrated that our universe is (at least at the quantum scale in-deterministic). In the standard Copenhagen interpretation we must assign probabilities to certain events, and we can never discount a certain event from occurring (such as an electron existing out at Pluto). Now this clearly demolishes the deterministic frame work, but what does it say about free will? This is where i disagree with the standard interpretation made by the likes of Kaku (See here http://bigthink.com/ideas/37862), who claim that this demonstrates we have free will. I agree that an observer would be inclined to state that a "mind" has free will as the observer can only calculate the probability of certain actions occurring thereby negating determinism.
    However consider the perspective of the "mind". From its perspective, no matter which course of action it takes, it will be unable to determine the results. Certain probabilities may be calculated, but is it not chance which decides the outcome of the event? The mind cannot be certain of that any action it undertakes will cause a particular event, and thus despite its will, it may not reach the desired result. Is this not a contradiction to the very definition of free will?

    On the other hand, if you subscribe to Everett's Many worlds interpretation (this world is the world in which x occurs and not x'), is not determinism left intact, and thus our free will negated?

    I am inclined to agree with Arthur Schopenhauer's belief that free will is an illusion, but i am not totally convinced. Compatibalists such as Dennett (see Elbow Room) disagree with my stance, but i believe they are confusing uncertainty from the perspective of an observer and ignoring the uncertainty of the "mind". I cannot find a modern philosopher who agrees with my stance, and this somewhat disturbs me, as i may be missing something crucial. I would like to hear other people's opinion on my stance and their advice for searching for sympathetic philosophical works.
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  3. Jan 16, 2012 #2

    I'm no philosophy buff, but I do think quantum mechanics is to often used carelessly indiscussions about this matter. In quantum mechanics physicists describe certain concepts like the electron (which is kind of the prime example of a particle) by determining a state or a possible state and then measuring whether this is actually it's state. This state then is quite robust it is the state of the electron (you could even say it is the electron). The difference with the deterministic view is that even once a state has been assigned this doesn't force the same results for the same experiment on an electron in the same state.

    So the state of an electron doesn't determine it's behaviour exactly but it does offer the probabilities of certain things happening and via pauli's exclusion principle for instance it also excludes some things from happening. In my view it doesn't pay to use these concepts in talking about free will. The description of a concept like an electron just doesn't have anything to do with free will.

    The thing that should be taken away from this is the way of thinking about things. Namely that something can have quite neat and well recorded properties and still not react the same way to the same situation.
  4. Jan 16, 2012 #3


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    There is also the idea that the systems that are described in nature are 'pseudo-random' and not actually random.

    The idea is that the deterministic nature of things is tied up in systems that are just so complex in the way of a mathematical expression (very complex), or in the number of variables involved, or a combination of both.

    Given that most people have problems when we talk about systems that go over say five variables, I wouldn't be at the least surprised if the pseudo-random argument was the case.
  5. Jan 17, 2012 #4


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    I generally think that free-will is an illusion; but free-will can be a big subject with different peoples having different connotations.

    I differentiate it form will-power. Will-power is an organism's ability to get what it wants. Free-will is the notion that the organism can choose what it wants. There's definitely will-power, but free-will seems like it would evade cause and effect and as far as we have measured, we don't do that.
  6. Jan 17, 2012 #5
    http://en.wikipedia.org/wiki/Free_will_theorem I think the nature of quantum mechanics is very important when discussing this subject. If nature is deterministic then we must understand the basic physical laws, which are quantum in nature in order to determine outcomes.
  7. Jan 17, 2012 #6


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    QM isn't needed to reproduce the action of neurons that we attribute to behavior. The system is treated classically and most arguments for quantum consciousness aren't taken seriously by the community. What you have linked here is the opposite point... a flavor of panpsychism it appears: concluding that particles must have free-will... but i'ts predicated on humans having free-will... which hasn't been shown yet. In fact, most experiments are interpreted to show the opposite.
  8. Jan 17, 2012 #7
    The introduction to this wikipedia entry reads:

    The free will theorem of John H. Conway and Simon B. Kochen states that, if we have a certain amount of "free will", then, subject to certain assumptions, so must some elementary particles

    This seems to me to absolute hogwash then. It is not hard to dispute the very existence of elementary particles other than in the way of a concept used by scientists to model certain situation. I only read the wikipedia article but it seems like they choose ´free will' to mean that the outcome is not predetermined. This seems to follow from quantum mechanics pretty easily. But the way it is presented there it seems to me to be only about elementary partciles and thus about the domain where quantum mechanics of quantum field theory is valid.

    If you model a certain theory by using another theory you can't just blindly assume it works. Quantum mechanics was partly invented because the model that we had for orbiting planets didn't seem to work for orbiting electrons. An example of this fact.
    If you use quantum mechanics to model a theory of free will you shouldn't use quantum mechanics to prove it, of course the model for your theory agrees with it!
  9. Jan 17, 2012 #8


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    Also one should realize that its not going to do justice to the problem to think in terms of purely isolated cases or in terms of segmentation.

    There may certainly be ways of using statistical analysis to describe mean behaviours and even "tail" behaviours but until we start at looking these things in more wholistic way, we are bound to miss important interactions that will give us the most valuable hints.

    Looking at a reduced problem is useful as its important to build up intuition so I'm not saying to not bother with understanding building blocks like say an electron or a neuron or whatever, but if we keep taking the approach of only segmentation or divide and conquer, then again many important effects will swept by the wayside.
  10. Jan 17, 2012 #9


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    There is an interesting parallel in that the choices being made with both QM and the brain are post-determined, not pre-determined. The constraints which determine the action lie in the future rather than the past. Well, there are constraints in both directions, but the "freedom" concerns what has not yet happened.

    In QM, this gives you the retrocausal view of the transactional interpretation.

    And with humans, it boils down to our ability to anticipate. We can imagine courses of action and predict the results of different choices. So we are constrained by future expected consequences rather than - in some direct fashion - a past history of events.

    Human freewill is like QM freewill in that the past does not completely constrain a systems degrees of freedom, further information is needed that comes from the future of the system. But while there is a causal parallel, the source of the brain's freewill has nothing to do with QM's indeterminism. In QM, the information would actually have to come from the future, whereas brains can only imagine their futures.
  11. Jan 19, 2012 #10
    How can you prove there is a free will? I believe in Determinism.

    oh! wait. Shall I drink water on my desk, now. I'm feeling thirsty. I can either drink and clear my thirst or keep being thirsty. Oh! I can choose. I have free will.
    Or maybe, what I will do is already determined by the configuration of neurons in my brain and the ambient temp/humidity etc.... etc. This is just so confusing.
    I quit, I can't answer. :)
  12. Jan 19, 2012 #11

    The universe(reality) is creative :)

    I am beginning to consider this possibility that arises from strong determinism
  13. Jan 19, 2012 #12

    The claim is that your choice not to drink water was made at least 13.7 billion years ago.
  14. Jan 28, 2012 #13
    I don't see what the philosophical problem is with free will...
    Whether the microscopic world is deterministic or stochastic, either way it doesn't have free will. This should be uncontroversial.
    But animals in the macroscopic world do have free will. They do by definition of the words free and will. If you argue that animals don't have free will then you are changing the meaning of the phrase free will.
    Why is it so hard to understand that a concept can exist at the macroscopic scale despite not existing at microscopic scales? This emergence happens all the time...
    wetness, elasticity, probably gravity, well anything really.

    The argument that free will doesn't exist because the underlying laws are deterministic or stochastic is about as sophisticated as claiming chocolate doesn't exist because there are no chocolate atoms, or that happiness doesn't exist because it can't be seen in the laws of physics.
  15. Jan 28, 2012 #14


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    Free will would evade cause and effect, undermining strong determinism. If an organism can act independent of how it's acted upon, it's evading cause and effect.

    In a completely stochastic universe, there's no cause and effect, so free will would be useless; you wouldn't be able to make anything happen, things just happen by chance, not because you caused them to happen by will (it would only appear that way).

    So at these two extreme ends, free will is paradoxical.

    Anyway, much of our behavior, independent of philosophical arguments, is empirically shown to be deterministic in the short-term; even when we feel that we are being spontaneous. Long-term is not as easy to test.
  16. Jan 28, 2012 #15


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    Yes, they may stand as limits on what we conceive as the possible. But why can't freewill (which would better be called intelligent choice of course) then emerge as part of the actual complexity of the world?

    I mean why does strong determinism have to be the case? And utter indeterminacy the only alternative?

    The very fact you can imagine such a thesis and its anti-thesis already opens up the further possibility of their higher-order synthesis. It's basic Hegelian logic
  17. Jan 28, 2012 #16


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    Right; my post was meant to be a pedagogical reply to Tglad's question, thus the qualifiers. I make no arguments about what the universe is; I just describe the philosophical foundations of the question.
  18. Jan 29, 2012 #17
    For me, the root of the problem is that people think of 'does free will exist' as a boolean question, rather appreciating that existence of a concept can vary with the level of detail:

    At a coarse detail level, e.g. in everyday conversation, referring to normal situations, using the colloquial definition of free will, we can say that people are able to make choices independently of others, therefore free will does exist at this level, as most people understand the term.
    At a fine detail level, e.g. considering interaction of atoms or the basic laws of physics, then free will clearly doesn't exist.

    So it is a high level property. Like wetness, or elasticity or sentience, or roughness etc etc.
  19. Jan 29, 2012 #18


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    Except there was nothing in TGlad's post to suggest he did not get the basic claim.

    Whereas you seem to say that determinism is an issue to do with "external" cause and effect, when the conventional view is that the difficulty lies with the workings of the brain/mind. And then you equate the stochastic to some kind of total lack of controllability, when most would think that probability is a measure of what actually is predictable.
  20. Jan 29, 2012 #19
    Free will, as I think it's usually used, refers to our volitional behavior -- an observation, not an assumption or, necessarily, an illusion. Taken in that sense, free will is compatible with the assumption that our universe is evolving deterministically in accordance with fundamental dynamical laws. So, if free will is taken to refer to our volitional behavior, then there's no problem.

    But if free will is taken to mean that we could have done otherwise, then, wrt that connotation, free will refers to an assumption that implies nondeterminism ... and sets up an, imo, unsolvable problem. That is, we're then back to pondering the apparently unanswerable question of whether our universe is evolving deterministically or not (though, imo, determinism is the more reasonable assumption).
    Last edited: Jan 29, 2012
  21. Jan 29, 2012 #20
    i always found it facinating how deep feelings are encoded and how the "i am" irreducible (at least in the psychological sense) consciousness part is encoded in matter...its pretty amazing
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