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Free Will?

  1. Mar 5, 2009 #1
    Well, I was in the car with my mom going to pizza hut and I was thinking about the principle that if you knew the exact positions and velocities of every particle in the universe, you could know everything in the universes past and future. It doesn't take too much thinking to realize that is true (bought the same amount of time it takes to get from my house to pizza hut). But, on the way back I began thining along those lines, but instead of the universe as a whole, simply on macroscopic standards.

    Now then, for my question, if you could know the exact position and velocities of every single particle in our brains, could you predict the owners thoughts, and, ultimately there actions. I don't see any reason why our brains should work any differently than everything else, in which by knowing the information of each and every particle you gain access to its past and future. If the brain does behave like that then it would mean that every single person's thoughts and actions, from Hitler's slaughter of the Jews, to Mother Teresa's benign actions, all depended on the initial state of every particle in the universe. My thoughts on my ride and ultimately my posting of this question, all depended on the initial state of the universe.

    Something like that is very hard to swallow for me, which is why I am asking you guys. It seems highly unlikely, but for it to be otherwise, the brain must work entirely different than any other physical system I've ever heard of. By now, the title should be obvious. Free-will can't be true if the brain works the same as every other physical system.

    I hate to think that Newton and Einsteins amazing thoughts only came to be because of the initial state of the universe rather than there own genuine intelligence.
  2. jcsd
  3. Mar 5, 2009 #2
    Your logic would be correct, except that your assumptions are incorrect. Classical mechanics is not an entirely correct theory, due to quantum mechanics' probabilistic formulation. In other words, in a quantum-mechanical system, one cannot accurate predict a particle's path... one can only use probability to "guess" it.
    Last edited: Mar 5, 2009
  4. Mar 5, 2009 #3
    First, no, according to quantum mechanics not every quantum level event is predictable. So you could not predict long term, ie from the beginning of the universe. Although short term, within the span of a human life, you could probably be pretty accurate.

    Second, freewill requires a deterministic universe. Without predictable outcomes, no choice can be made. Everything would simply be random, regardless of what a person intended.

  5. Mar 6, 2009 #4
    If you could predict your own thoughts, then your thoughts would be different and end in some horrific endless loop which seems to be why we can't actually measure a particles exact position and velocity. In that sense we have free will, because being part of the universe means interacting with it. However a being disjointed from the universe (god?) would be able to correctly predict the outcome of the universe from start to finish. All the laws of physics have led to us here now. Theres no 'chance' about it.
  6. Mar 6, 2009 #5
    Are you considering Heisenberg's "uncertainty principle", and if so, just because "we" can't predict certain events does it necessarily follow that a deterministic universe is not the situation?

    Although we have no accurate means of locating both position and velocity of certain things, does it mean that what happens on all scales is anything but a result of the idea that what came before determines what comes after?
  7. Mar 6, 2009 #6
    Normally I hate quantum theory becuase, quite frankly, I have trouble understanding it. But, at least it can keep us from having the kind of universe I described, which would just make everything in the universe seem pointless. Thanks for all the replies:smile:
  8. Mar 7, 2009 #7
    Meh, this debate always comes down to the two points:

    A: Even though one cannot praedict precisely the path the particles will follow, your mind is still a slave of the laws of physics, thereto, no free will.
    B: Obviously there is free will if you cannot praedict particles.

    It's obviously a matter of defining the concept of 'free will', it's a 'true by definition' situation depending on how you define it.

    Also C: Obviously quantum mechanics is bollocks and just an abstraction layer we have today which seems to explain the events how we can measure them today. There's probably another theory coming up, (which might even be consistent with the mother load of General Relativity, who knows?) which might be deterministic .

    I agree with C.
  9. Mar 7, 2009 #8
    Yeah, even though free-will might be a little blurred, I would want C also. When I first really thought about quantum theory, it didn't seem to fit right at all. I had learned Newton's laws which explained the entire solar system beautifully, the special relativity, that had some weird ideas like time slowing down but ultimatly allowed all frames of references to be equal. Quantum theory didn't seem to fit in with all those symmetries. But, as of now I suppose quantum theory is just as good at predicting as GR, so I suppose I really couldn't pose any argument against it, right now anyway.
  10. Mar 7, 2009 #9
    Well, obviously GR > QFT on praedicting. As for one, GR praedicts exact values and QFT only the chance that value will take. So GR is a lot better to verify empirically. In theory we could always say 'Even though this does not stroke with our probability density function at all, it's a probability function, who knows? Just bad luck?'
  11. Mar 7, 2009 #10
    I vote for not worrying at all about whether or not we have free will. I know it seems pretty strange to say such a thing on a science board, but I mean it. Sure, you could analyze every choice you make wondering whether you chose to do this instead of that, or if you were always going to do what you've done and you only thought you had choice, but where would you be when you discovered the truth? If you figure out everything that has happened and will happen was going to happen from the exact instance of the big bang, then you'd also have to understand this discovery was going to happen also, and so was your reaction, and the effects of that reaction. Or, you can discover that we really do have free will, and you'll go on making choices, and those choices will have effects, so on and so forth.

    The point I'm trying to illustrate is that scientific exploration and discovery may one day solve this riddle, but let it be the by-product of discovery. Focusing on it is a waste of time, and the gooey stuff you have in your head could be put to much better use.
  12. Mar 7, 2009 #11
    I believe the contrary, sure there are a lot of 'scientific' things which are of great political interest to have an answer to, to fabricate an answer to. Things like the existence of gods, the existence of purpose, the origins of life, multiverses and so on but their answers are next to scientifically irrelevant as they really do not provide any implications in other fields at all. Suppose we have free will and we can prove it, then what? What does that imply? Same with all the other questions.

    They are politically important because various justifications of ideology can be drawn from then (by crude logic), I don't think they are scientifically that important at all. At this state, saying any about it is also a common fallacy people forget that you aren't forced to provide an answer when you simply do not have enough information to make a funded conclusion. Saying 'I don't know' is the scientist's answer to the vast bulk of questions people will ask him.
  13. Mar 7, 2009 #12
    I definitely understand the ideological importance of such questions, but I also think we'll come to those answers in time, regardless of whether or not we were looking for them. But, and this is very interesting (if not totally maddening), there are certain *ahem* ideologies that wouldn't be affected by such amazing scientific discovery. Considering my own experiences, I feel like I've come across enough evidence to disprove the existence of what is commonly thought of as "God". But, all of that evidence is turned around on itself by Creationists and the like, and said to be placed here or allowed by God to test our faith.

    Unfortunately, finding the answer to the question "Do we have free will?" wouldn't be powerful enough, despite how powerful it would be. I think our constant scientific discovery is doing the best job possible to address these issues. I like to think about the field of science like a very effective argument. We'll just keep introducing more and more information until it is impossible to deny. All we can do now is hope the world isn't gobbled up by socialism, so that we may continue our level of exploration and discovery.
  14. Mar 7, 2009 #13
    Disproving the existence of God as defined in the Library of the Christian Faith or he Recitation of Islam isn't that hard, for instance, God is defined there as He who flooded the earth later than 6000 years ago. Clearly that never happened science tells is ergo this one Man doesn't exist. However be cautious that that is not a proof that no god exists. The major fallacy people also always make when they attempt to proof that no god exists is that they forget that 'a god' needn't reveal itself to its creation. Maybe there is a god but simply not documented in some vague Earthen Sanskrit scripture in the Old Brahmic script, also: http://thisdomainisirrelevant.net/198 [Broken] should illustrate that the arguments to do so are often very selectively chosen and indeed imply a lot of other things. For instance that good manners like here are a load nonsense and trying to teach them to others is imposing your faith for which you have no scientific explanation unto others. Science and logic can be let loose upon morals, with ease even, the point is that Lady Science is immutable and strict and the conclusion is not chosen but investigated and there is no field where there is more political desire to have a certain outcome than moral. The truth is that 'good manners' are as much nonsense as the great flood and if you have troubles accepting this then I hope you see how people have troubles accepting the great flood was never there. People have manners because it was insinuated to them as a child how they should behave, the same for the great flood. Free will however seems to be derived more introspectively.

    I still fail to see any implications a positive or negative answer to the free will question has for any relevant fields, and that is why it can't be answered, it's independent from all the other things we can test, compute and measure and thus the model remains consistent with assuming either one or the other making it not only irrelevant what it is but also simply not possible to investigate it. It's like trying to proof CH from ZFC.
    Last edited by a moderator: May 4, 2017
  15. Mar 7, 2009 #14
    As I alluded to before, I believe there to be plenty of proof against a Judeo-Christian, Muslim, etc "God." So, no arguments there. However, I have a hard time conceding that there may be a conscious being who just doesn't let his presence be known. This may very well be the case, but I don't think so. If it were possible for a god-like being to exist, I'd bet on the watchmaker analogy. But, that's a moot point because I subscribe to the idea that "God is Math". There is definitely a lot to understand, and we may never understand: Where does are universe reside? Where does what our universe resides in reside? So on and so on, infinitely. Math is obviously the key, whether it be in Astronomy or Physics, and I can't wait to see what advancements will continue to be made using math in the name of science.
    Last edited by a moderator: May 4, 2017
  16. Mar 7, 2009 #15
    If I were an omniscient God, I would know that the distinction between 'life' and 'lifeless' matter isn't really that important and the only thing in my universe that pays so much attention to it regardless of all their best efforts to try to define it which have failed are a species who in their own egocentricity called themselves 'the wise wise man' in a dead language which was praeviously mainly used a vessel for conquest and more egocentricity.

    I really doubt we are that interesting in this vast universe to an omnipotent and omniscient creator really, a speck of dust in the desert, little more. If we aren't that interesting to even other forms of 'life' on this planet. I really see no reason at all why a 'god' who did not create us in his image (again a symptom of human egocentricity) who does not share human cultures of right and wrong (again) who does not have the only people who believe in Him as his chosen people (well...) to have any business 'revealing Himself' to us. if he shares our sense of humour he would simply laugh because another human just assumed his species the centre of the universe without any direct prompt towards it. Out of this bucket come ideas like that Terra is the centre of the universe and all other things rotate around it.

    Math is useless here. People doing 'maths' every day fail to realize they use a very specific portion of maths cultivated for the use of investigating the universe, namely, Hilbert-style deduction famously implementing the modus ponens, formally:

    [tex]\{x \to y, x\} \vdash y[/tex]

    Or 'If we know that x implies y, and we know x is true, we then may conclude y', is this an absolute rule? no. It's just a rule which we have empirically seem happening countless times, this is no more proof that this is 'true' than would be proving Fermat by just trying out 'a lot' of cases and see that it indeed cannot be done there. Little mathematicians do not use the modus ponens in their work and not stating any rule of interference implies using it from context, however it's still just a rule of interference and there are a lot others we can choose from. Those others might be very applicable in 'another universe', people often fail to realize that another universe needn't just imply another set of physics, but also perhaps another set of maths? Does the concept of 'maths' make sense in another universe?, can we test if it does? no, we cannot reach out of our universe per definition, do all these questions have any relevance or make any sense, not at all, you're asking yourself what the colour of an invisible unicorn is.
  17. Mar 9, 2009 #16
    Can you please explain to me the idea of the "B" point. Are you suggesting that because we cannot predict (at least as of yet) particle activity that free will must exist. You use the word obviously when it seems obvious to me that not being able to predict particles, as you put it, can be a result of the cause and effect activity going on within our intellects that so far have prevented us from being able to know how things will always turn out even though this lack of ability is a deterministic product of our lack of potential.
  18. Mar 9, 2009 #17
    I've never understood the fascination with this free will question. It really doesn't seem all that interesting, in the end whether we have free will or not doesn't matter. If we somehow found that answer that we in fact have no free will and that our lives with play out in some order determined by the laws of physics, what should we do about it?

    The original opp said

    "I hate to think that Newton and Einsteins amazing thoughts only came to be because of the initial state of the universe rather than there own genuine intelligence."

    That doesn't seem to make a whole lot of sense to me. Are you trying to suppose that Newton and Einstein's genius where somehow products of something that don't follow the laws of physics? Then you'd have to postulate supernatural causes.

    The key thing is to remember is that just because we are conscious does not make us something outside of the universe, we are the universe. What is so wrong with that?
  19. Mar 9, 2009 #18
    Its simple really. If you murder someone, and you have no freewill, then *you* aren't really responsible. Would you punish a car for being out of oil? Would you blame the moon for not being as bright as the sun?

    In Christian mythology you go to hell for your choices in this life. In Islam you choose to submit to the will of Allah. The Hindus have karma... which demands a different idea of freewill.

    Whether freewill exits, and how it works, is incredibly important to how we live.
  20. Mar 9, 2009 #19
    That's an interesting point, but there is something you're missing. If thought is a result of the movement of particles as determined by the Big Bang, and therefore they can be predicted, then it stands to reason that free will isn't important to our way of life, because all of our thoughts, which dictate our way of life, are simply coincidences. Our way of life isn't important either. It is to us, but our feeling that it is important is just a coincidence, too. And if civilization would begin to unravel when we found that there is no free will, it would seem as though that discover was the important moment that led to the end, but that moment wasn't important at all. In fact, if we have no free will, and everything was determined at the instant of the Big Bang, than the only thing of any importance is the Big Bang.

  21. Mar 9, 2009 #20
    I disagree with you here, quantum mechanics isn't like statistics where you guess the outcome of a deterministic experiment because you lack the data to actually deterministically compute it. Its is the way in which nature behaves. Of course probability is a model in which we use to describe it but even the very simple idea of saying where the position of an object (at a quantum level of course, I am trying to avoid saying particle) is very hard given that the object is both a wave and a particle. These objects also behave as though they act on all the probabilities if you do not collapse the wave function.

    The things said in this thread were precisely what philosophers were saying about Newtonian mechanics. If it were true, then we would have no free will (it is impossible to define a sensible definition of a free will). This however is not the case. Even if you cannot predict the particles in deterministic system does not mean that you have free will. It just means you can't see into the future, we still loose our free will. As long as you have that the paths of the particles are predictable, you loose free will. Same goes for an omniscient (in the true sense) being.
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