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Logical supervenience and interactive dualism.

  1. Jan 26, 2006 #1
    After reading (most) of Chalmers "a conscious mind" book I was left with quite a good argument for experiences failing to logically supervene on the physical, no matter what the level of analysis (biochemical, functional etc). For example Mary the neuroscientist, Nagel's Bat.

    However it seems now as I talk about my experiences that there is some causal link between my experiences and my typing. I am rather unconvinced by any epiphenomenal view that says i would sit here and type this if my body was "dark" on the inside, any further unconviced by the proposition that Chalmer's zombie would have authored the same book.

    I know interactive dualism is pretty much blasphemy in todays world of cognitive neuroscience but given

    1) experiences are something above and beyond the physical, and
    2) experiences effect the physical,

    how is 3)interactive dualism is true, not a reasonable conclusion.
  2. jcsd
  3. Jan 26, 2006 #2


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    The reason interactionist dualism is not a popular view is that it infringes too much on territory already staked out and well-established by physics. If interactionist dualism were true, this would imply a number of problematic things, e.g.:

    1) some activity in the brain should be observed to violate physical laws;
    2) our behavior cannot be entirely explained by the conventional neuroscientific approach (although there is much work to be done in terms of understanding the brain, there are no indications that our neuroscientific understanding of behavior should run up against such a wall);
    3) we would need to come up with a theory to explain how the physical can interact with the non-physical mental stuff of the mind; etc.

    On the whole, interactionist dualism is not indefensible (though it may eventually be someday, e.g. if and when we can come to a complete and sufficient physicalist account of behavior). However, to commit to interactionist dualism is to wager that there is some heretofore unforseen and undetected, yet hugely significant, flaw in physical theory's ability to describe the objective dynamics of nature-- and on the whole, that doesn't seem a very wise bet.

    Well, this is a bit tricky. If you are committed to the stance that subjective experience is not logically entailed by the physical, then you already have granted the logical possibility of zombies. It's inconsistent for you to believe one but not the other-- think about it.
  4. Jan 26, 2006 #3

    I agree that Chalmer's zombie writing his book is logically possible, However for the case of epiphenomenism in this world I think it is a counter example, let me explain.

    Imagine this universe began 13 billion years ago exactly the same except that experiences were not included (assume for the sake of argument experiences don't logically supervene). I can easily imagine all non human life would evolve and behave the same way, I can even imagine that humans would evolve and use language that refer to things out there such as rocks, as this language would perform a physical function that is adaptive for that species. These humans may also use language to represent internal states such as hungry of tired, as long as speaking these words performs some function in the physical world.

    Although it is logically possible they would sit down and write a book like the one Chalmers wrote, it seems to me that this is to a lesser degree like a monkey sitting at a typewriter and typing out a verse of shakespear, it is logically possible, but with a monkey brain so unlikely we would call it impossible in any pragmatic sense. It also seems to me incredibly unlikely that our non experiencing humans would sit round and say stuff about "logical supervenience of the experiential" when it refers to nothing in the physical world in the way that hungry or tired could refer to something in the physical world.

    If this is true then it still seems there is a case for non supervenience of the experiential naturally leading to interactionist dualism
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