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Free will from a scientific perspective [not philosiphy]

  1. Sep 1, 2007 #1


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    I was with a group of religous friends and they started talking about the "true meaning of prayer". I felt like changing the subject so I diverted the conversation to the question of free will. I said that since the brain controls what the body does and the brain is a physical entity which behaves according to the physical laws, it's theoretically possible to predict what someone will do. They were shocked at the idea and responded that:
    1) Don't you "feel" that you have free will just as you "feel" that you're alive?
    2) There're things in the body beyond the physical world, so physical laws don't matter in the body (ie: "who tells the brain what to do"?)
    My question is, is this a pointless philisophical argument that should stop here (like the question if god exists - been there already), or is there anything else of scientific value that I can say?
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  3. Sep 1, 2007 #2


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    I don't think there is anything you could argue with effectively. People believe what they want to believe.
  4. Sep 2, 2007 #3
    people who don't think physical laws govern everything can't be argued against using an empirical philosophy.
  5. Sep 2, 2007 #4


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    When dealing with this scientifically, we cannot avoid in looking at what we get out of quantum mechanics. After all, if there's any scientific theory that can turn things inside out and go beyond our everyday understanding, it's QM.

    Interestingly enough, t'Hooft wrote a while back of his own formulation that shows the possibility of determinism beneath QM. But that's not the end of it. It turns out that if t'Hooft is correct, then this implies that we do not have any free will!

    This whole progress along this line (something you won't find if you read the Philosophy forum) is now calling into question on how we define "free will" in the first place. You'll notice that this is a similar development with us having to redefine what we mean by "space" and "time" after the progress made in Special Relativity. This is just another example on how our successive understanding of the physical world caused us to reexamine and redefine something that we thought we understood.

  6. Sep 2, 2007 #5
    Benjamin Libet (2002) conducted some interesting experiments designed to determine the timing of conscious willings or decisions to act in relation to brain activity associated with the physical initiation of behavior.

  7. Sep 4, 2007 #6


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    The implication that determinism rules out free will, and related attempts to reconceptualize what we mean by "free will," are nothing new. These issues have been raised at least since Newtonian physics if not earlier. (Newton popularized the notion of determinism but he didn't invent it.)

    In any case, it has been well argued that the kind of "free will" allowed by quantum indeterminacy isn't a kind of "free will" worth having in the first place-- maybe you could have acted differently, but if this freedom is grounded in fundamentally random physical events then it is not something that can be guided by deliberate thought. So the worrying over the idea that abolishing quantum indeterminacy abolishes any chance at "free will" seems misplaced.

    Although, there is a line of psychology and cognitive neuroscience research that suggests deliberate thought and conscious volition in general is not causally responsible for our actions anyway (something you won't find if you read the Physics forum). So the issue of whether the universe is deterministic or not may be moot.
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