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Free will and predictability

  1. Nov 7, 2010 #1
    I'm new at philosophy (not so new at physics though), I mean, I haven't read much about it, so please bear with me if I'm asking something obvious.

    A couple of days ago I realized that assuming humans obey the laws of physics we know so far, there's no place for free will. Free will is something hard to explain for me, so I'll ellaborate a little more on my idea, and hope you (and I) understand what I mean by free will.

    Suppose you have to make a decision on something anyone would think can make a decision, for example, when choosing what to eat at a restaurant. The desicion you take must be the result of some physical phenomena in your brain (assuming we make our desicion with our brains), these physical phenomena obey the laws of physics we know so far, and so you don't really choose, you just evolve as a system under certain constraints.

    I know that we cannot predict the evolution of a system such as the human brain, and for what I've read (which isn't much) there's some relation I don't understand about not being able to predict something and therefore possessing free will. But what does predictability have to do with the fact that the desicion we take is just the evolution of a system? The fact that we can't predict the evolution of the system doesn't mean we can decide the path the system will take right?

    Ok, now I understand a little more what I mean by free-will. Free will is the ability to change the path of evolution of the system, when the system is our brain.

    By the way, if you find some error in my english please inform me.
  2. jcsd
  3. Nov 7, 2010 #2
    Lots of threads on free-will topic here around. In short, I agree that physical laws are firm and unbreakable, but free-will is element of consciousness, and consciousness is not just physical, even if it emerges out of it, or on top of it, and as such, it can make free-choices.
  4. Nov 7, 2010 #3
    Yeah, a lot of philosophers today are determinists.

    However, another way to look at the issue is linguistically. When words like free will and determinism are applied to such broad contexts as life, the universe, and everything they become meaningless. It's like saying everything is "pure energy" when the simple fact is energy is defined by mass and vice versa. Maybe everything is pure energy, but what the heck does that mean and how useful is such a statement?

    Spinoza speculated that only the universe en toto was free because by definition it has nothing to constrain it. Likewise we might say there is nothing to constrain the laws of nature and, so, ultimately they are free. We can go round and round and round juggling abstractions without ever making a single demonstrably coherent statement.
  5. Nov 7, 2010 #4
    Free-will. To be a will it must be a cause. As you think it must be able to change the path of evolution of the system, it must be external to that system. Now pick your best candidate. Supernatural 'something' or our natural perception of the natural world.
  6. Nov 7, 2010 #5
    IMO: We all feel we have free will, but among the choices we each have, we always choose what makes us the "happiest". And the "happy" feeling is just a series of mostly deterministic (or quantum mechanical)) neurological/chemical/physical reactions.

    Our individual futures are deterministic because just like ants, we'll each undoubtedly go where food, oxygen, proper temperature etc. is easier to get.

    But I'm ok with that! It's the feeling (of free-will) that counts, and it will always be there. I don't find any disagreement between determinism and free-will.
  7. Nov 8, 2010 #6
    what arguments do you have to say that consciousness is not just physical?
    Last edited: Nov 8, 2010
  8. Nov 8, 2010 #7
    You mean you don't find any disagreement between determinism and the feeling of free will.
  9. Nov 8, 2010 #8
    You're right about the usefulness of that kind of statement, there's no practical use (apparently anyway) to such a thing like not really having free will. And I guess it would be very hard if not impossible to demonstrate that we don't posses free will, in fact it would be as hard as demonstrating that everything is indeed physical.

    But the thing for me (someone who does believe that everything is physical), is that if my reasoning is correct, as a consequence of everything being physical there's no such thing as free will, just an illusion of it, so it doesn't need to be demonstrated directly as it is a consequence of something I take for granted. I assume everything is physical and go from there.

    Though it may not be useful to realize something like that I don't think it's meaningless. It's kind of like the question about death, you die and that's it? or your soul (or whatever) goes on?, you can't do anything about it, knowing it doesn't have any practical use besides changing the way you think about life.

    So I guess I feel it is important to realize that we don't possess free will, because although it may not be of practical use in science and/or engineering, it has some practical value in the way you take life (even if you don't have a choice at all!)
  10. Nov 8, 2010 #9
    If practical value is what matters then why not just focus on that rather than assuming that everything is physical?

    For me it is most useful to remain unbiased. Thus I can remain open to using a screwdriver even when it at least superficially seems that a wrench should work better. I don't need to take a metaphysical stance and can instead merely allow myself to be open to the possibilities. This is the great strength of the sciences, not physicalism.
  11. Nov 9, 2010 #10
    Could freewill be like the uncertainty principle in QM? You can have a prediction based on data/evidence but the result is not known until the measurement is made?
  12. Nov 9, 2010 #11
    I agree. There's a video out there on YouTube or somewhere in which Daniel Dennett makes this point too. Some people do seem to equate unpredictability with free will in this context, but unpredictability is hardly free will in any normal sense of the expression.

    I just read your posts very quickly, but your English looks pretty good to me.

    I'd replace "like" with "as" here.
  13. Nov 9, 2010 #12
  14. Dec 21, 2010 #13
    That link was interesting, thinking that there's no free will takes all the responsability of your actions away from you, what about those who argue that belief in free will is harmful to society on a larger scale, where can I find that?

    (Thanks for the correction)
  15. Dec 21, 2010 #14
    Is the universe constrained by its own nature?

    I believe in the act of freely choosing a decision, however, I do not believe in the concept of having total free will.
  16. Dec 21, 2010 #15
    -In regard to your third paragraph.

    Your theory seems solid, but I leave you with this to ponder, andresordonez, it may seem that we have no free will. But it is my belief, that the decision that results from that physical phenomenon is based on the person in questions individuality, so though a phenomenon makes our decisions, is it not the same decision we would make (if possible) in absence of the phenomenon? (pardon my graphical errors)
  17. Dec 21, 2010 #16
    andresordonez, I trust you have an imagination and I trust that you dream. The objects in both are not physical. In fact, the objects may not even be physically possible (in the strict sense of the expression). They are nonetheless "something". They are thoughts. Einstein's thought experiments are excellent examples. It is certainly not possible to ride a beam of light, but such musings lead him to develop the theories of relativity. "Everything" therefore is not physical and non-physical things can have meaning.

    Specifically to free will, have you considered the ramifications that Bell's Theorem has to the question? Quantum uncertainty seems to undermine determinism and so predicates free will.
  18. Dec 21, 2010 #17
    Could you explain that in a bit more detail, ynaught?

    Dreaming or thinking takes the form of non-physical objects… What I am wondering is whether that same form of dreaming and thinking follow the rules to an extent of the physical laws or what could be inferred by them? Alternatively, in other words, whether those same thoughts or dreams are guided by the extrapolation of physical objects? I am thinking of a nail, is that nail non-physical?

    I did not get it exactly...
  19. Dec 22, 2010 #18
    Well it's not like I'm 100% sure that everything is physical, it's more like if I have to make a bet I would go for saying that everything is physical. I'm like 99% sure that everything is physical (if such thing can be measured at all) given that for the relatively short time we've been doing physics (I mean the humans), we've been able to explain SO MANY phenomena. So it's something similar to the way I feel about god(s), I don't rule out the possiblity that there some kind of god, but I do everything like if there was no god.

    Another example would be the fact(?) that we don't know if we're asleep right now, or that maybe we're just a simulation of a supercomputer, or anything like that (I realize that I don't know much about these ideas, so I might be plain wrong), I haven't ruled out that possibility, but in practice I forget about that.

    By the way, how is it useful to think that there are phenomena that are not physical?
  20. Dec 22, 2010 #19
    Well, I think that's the question we're talking about, can we make our decisions in absence of the phenomenon?

    (I think you meant "pardon my grammatical errors", I just found one "... person in questionS individuality...", I think that "s" is not supossed to be there)
  21. Dec 22, 2010 #20
    You're right about I having dreams and imagination, but I think your argument for saying that thoughts are not physical is flawed. The fact that we can think of something that is not physically possible, like riding a beam of light (I'm not an expert in relativity so there might be some strange way to do this, but let's assume that it's not possible to do such a thing) doesn't mean (or at least I don't see it clearly) that our thoughts are not physical in the sense that we cannot explain them with physics.

    I realize that conciousness is a phenomenon that right now we can't explain at all (I don't know much about neurology and that kind of stuff, so maybe we have explained some things by now), the brain itself is something we don't understand very well yet, but so was the light, the movement of planets, etc, some time ago.

    About the uncertainty principle, you should read what I wrote at the beginning (if you haven't). I don't see how the fact that we can't predict the outcome of a measurement means that we have free will.

    I haven't read Bell's theorem. According to wikipedia it says:

    "No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics."

    I don't know what ramifications of this theorem you are referring to.
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