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Free will is an illusion?

  1. Aug 6, 2013 #1
    About two weeks ago I read Sam Harris’ book Free Will. Harris' thesis is that free will is an illusion. The following is a very brief summary of his reasoning: All humans’ behavior is entirely controlled by the physical properties of their brains. A person did not make his or her brain. Therefore, a person does not really control their own behavior.

    What do you people think about this? The thesis and his argument certainly has made me think.
  2. jcsd
  3. Aug 6, 2013 #2
    I thought about that long before Sam Harris started speaking about it.
    Everything you do is a result of your experiences, your genetics, etc. If we could take everything into account and put it in a powerful computer, it could probably predict how you will react to every situation, what decisions you'll make, and maybe what you will say at what times, making free will nonexistent.
  4. Aug 6, 2013 #3
    My instinct is that there is free will even if it's conceivable that 99% of our actions can be predictable. That last 1% could still be chaotic and unpredictable.
  5. Aug 6, 2013 #4
    I believe that we as humans have choices, and we can weigh up the outcomes before doing them. So we have free will, I can go kill someone tonight, or I can chose not to... it is free will, I'm making my decision freely.

    We can predict that when an unbiased coin is flipped, it will have a 50/50 chance to land on heads or tails, but if that coin had the ability to chose what side to land on, the coin now becomes unpredictable.
  6. Aug 6, 2013 #5
    You have the ability yes, but whether you will or you won't is different and that can be predictable given the calculation of necessary factors. I also could kill someone right now, but I won't and the reasons why aren't very mysterious to calculate if you study me. Humans aren't coins, unless they have a mental illness. We do things for reasons, these reasons can be discovered. All day we are motivated by internal and external factors.
  7. Aug 6, 2013 #6
    Hmmm, well although we can't control our electrons ect we can control what information they carry and what the overall brain does. when you drive a motorcycle you can't control the individual engine parts, but you can control the larger picture, ie the speed.

    So I guess if a computer could analyse every electron in our brains and calculate every single factor then I guess every part of us could be predicted, but I don't think a concious thing can be predicted.

    Sure I could say if I yell at you you'll punch me, but I don't think you could predict that i'll drop a coin in 18 hours 32 minutes 11 second time and when I bend down to pick it up, i'll move my hand at a certain speed and at a certain angle, and my left knee will bend x degrees ect.
  8. Aug 6, 2013 #7


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    the question of free will isn't whether we make choices; it's whether or not those choices are predetermined.

    Free will appears as mysticism to me. It follows along with the concept of a soul. There doesn't seem to be any reason that we should avoid the chain of causality just because we're living: we can explain all of the things that differentiate living from unliving via deterministic mechanisms.

    There's really no need for a concept like free will to explain human behavior. It's just a subjective feeling we have.
  9. Aug 6, 2013 #8


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    also, predictability and determinism are not mutually exclusive. Chaotic systems are a class of deterministic systems that are inherently unpredictable.
  10. Aug 6, 2013 #9


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    Sorry, this is "philosophy" and not science.
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