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Some more vague questions about consciousness.

  1. Aug 15, 2012 #1
    [I'm using the word "consciousness" to basically mean "capability to have an experience".]

    Assume there was a machine that could instantly destroy and/or create a perfect replication of you. It does both of these functions and incinerates you, making a perfect copy of you 10 feet away.

    Most would agree that the original "you" would die when you were destroyed, and a brand new life would begin afterwards. Otherwise, what the hell happens if it makes a clone of your self while you're still alive? Do you experience having two selves?

    The copy of you would be a brand new consciousness that was just born, even though it would retain all of your information and fully believe that it was the original "you."

    But the question is: why does the original you not experience being revived? If I walk 10 feet from point A to point B, I am now 10 feet away than I was a minute before, but otherwise the exact same object.

    If, instead, I teleport from point A to point B, I am still 10 feet away than I was a minute before, but otherwise I am the exact same object... except I'm dead, and an imposter gets to live my life.

    So if your bodies in either of these scenarios are materially the same thing, what was left behind? Why, if I teleported, am I dead and replaced if the universe looks basically the same as it would had I walked? What's the material difference?

    Even recreating a dead person's brain and restoring it artificially would, theoretically, leave them dead and replace it with a new consciousness, because the original "them" died, correct? If this is the case, then your consciousness is strictly the stream of chemical reactions inside of your brain, rather than a physical component of the brain itself.

    If one were interested in finding a way to have their consciousness survive past the death of their brain, they would simply have to continue the chemical reactions taking place inside? Like have an organism's brain hooked up to some artificial "blank brain" and allow reactions to leak into the new brain? Or create an artificial brain ahead of time and have one consciousness leak into it?
    Last edited: Aug 15, 2012
  2. jcsd
  3. Aug 15, 2012 #2


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    Look into John Hick's replica theory. It explores a lot of these issues. Otherwise three points:

    1) In body and mind human beings are like Theseus's ship. Over time we loose little bits and gain little bits. Most people instinctively (and this applies to most objects) feel that if there is too much change at once then the continuity is broken and the object is new. At the heart of it the issue is of continuity.

    2) Many would argue that for all practical purposes a perfect (or even near perfect) replica deserves rights to the same identity.

    3) The reason the original does not experience anything is because their consciousness dies with them. The second person will remember it all but that's similar to the Omphalos hypothesis and links back to the continuity issue.
    Last edited: Aug 15, 2012
  4. Aug 15, 2012 #3
    So consciousness is strictly chemical processes happening over time in the brain, right?

    If one wanted to survive brain death, could they potentially have someone surgically attach a brain to theirs to accept electrical pulses chemical reactions until the new brain is fully active? And it would be "you"? Again, assume that we have all of the technology to do this (unless it's impossible). I don't see why this wouldn't work if consciousness is purely ongoing chemical reactions.
  5. Aug 15, 2012 #4


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    That is not how the brain works. Whilst we don't have a solution to the hard problem of consciousness (i.e. how consciousness arises from physical phenomenon) we have a pretty good idea that consciousness is the result of neural networks. The section I've highlighted in your text really makes no sense when you consider what we know about the brain.

    Something similar to what you're proposing is the Moravec proposal for mind uploading. Beyond philosophical thought experiment this is no more than science fiction but the basic premise is similar to the Ship of Theseus. Briefly: imagine we could infiltrate the brain to such a small level that we can replace brain cells (neurons and glial) with synthetic ones that do a similar job. The difference is that when a synthetic cell recieves an input rather than the outcome being determined electrochemically inside the cell it broadcasts to a computer that simulates the effect before transmitting the appropriate response back. Now imagine that one by one we replace the hundreds of billions of cells. Eventually we get a situation where the brain is being fully simulated on a computer. The questions around that centre on where "you" now are, are "you" the same etc.

    Please note that discussions on things like this in any other fashion than a thought experiment are overly speculative and against the rules. Let's not go there.
  6. Aug 16, 2012 #5


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    I speculate that the material difference would be spatial location. It sounds obvious and dull, but space is the only thing that can distinguish subatomic particles. If you put two electrons in a box, they are literally indistinguishable (this is an important property underlying their quantum nature). It's not a matter of a human not being able to tell them apart; one electron may as well be the other. Except with spatial separation; if I have an electron in Boston and you have one in London, we can distinguish them.
  7. Aug 16, 2012 #6


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    This does not meet the requirements for philosophy.
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