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The teleporter paradox

  1. Mar 21, 2003 #1
    This is a well known paradox in the philosophy of mind and has been used as an objection against the materialist thesis (that everything that makes up the human mind is physical).

    The year is 2500, and teleportation technology has been perfected for use on humans in interstellar travels. This is how the human teleporter works: instead of actually sending you (with all of your atoms) through space-time, it simply scans your body, capturing all the information on every subatomic particle in your body at an instant (assume that they got around Heisenberg's uncertainty principle), at which point your body is destroyed (don't worry, you are put under anaesthetic for the procedure), while the information of those atoms gets transmitted to the destination, where a machine will synthesise an exact replica of you (exactly the same down to the subatomic level) using new atoms. You then wake up in a different galaxy (after the anaesthetics wear off - and the anaesthetics would also be 'teleported' by the way), with all your memory before the teleportation intact, convinced that you have survived the procedure. Of course the atoms are all new, but isn't the new body still the same 'you'? (In real life, every atom in our body eventually gets replaced anyway.)

    Now let's add a twist. Instead of destroying your original body, it is preserved during the scanning process. So now we have TWO copies of you: the original one, and the replica. Both of them are identical down to the last atom, and should be behaviourally indistinguishable (because they have the same physical makeup, materialism states that they must be identical in every way.) But surely you can't be in two places at once! If 'you' survived at all, isn't it obvious that you survive as your original self, not the clone? But what's the difference between your original self and the clone anyway? Both of you would behave in exactly the same way, and both would have the same thoughts (at least initially, when there has been no divergence in the environment). So did you really survive the procedure afterall? If you didn't, doesn't that point to the existence of something other than your physical body including the information contained within the arrangement of the atoms? Is there a difference between the scenario with one original body and one clone, and the scenario where I destroy your original body, and create two(or more!) clones instead? In each case, is it so clear that 'you' will survive, and survive in one of the individuals/clones?

    My view: I prefer using a more mundane example - one that all of us have experienced: sleep. Each time we wake up, we feel that we are the same person as the one we were the night before, because there is a sense of continuity. The fact that nobody is able to 'clone' us during our sleep ensures that our identities remain unique. Imagine if I clone your body during sleep and destroy the original body, your clone would still wake in the morning, unaware of what has happened. Nobody could ever tell the difference between your clone and your original self.

    The fact is that when we wake up each morning, we are no more certain that our bodies are the original ones anyway. You would not notice if I replaced your brain with an exact replica. So it is not the temporal-spatial continuity of our bodies that ensure our psychological continuity, but rather, our memories (encoded in a physical form) together with the information-processing apparatus capable of using them.

    As for the dilemma about 'multiple selves', I don't think my response can satisfy everyone . . . but here it is: I think we should give up on the idea of the existence of an immutable, essential 'core' of ourselves. There are no real selves, only the semblance and perception of them - and it's a mistake to treat such impressions as a 'real' entity. So if I make five clones of you, then 'you' would survive as 6 individuals - even though there won't be a united 'you' who get the experience of all 6 persons at the same time. The question: 'who would YOU survive as?', tempting and obvious it may be to ask, makes no sense because there was never a real self to begin with.

    So what do you think?
  2. jcsd
  3. Mar 21, 2003 #2

    Tom Mattson

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    Perhaps I'm missing something, but this "paradox", if true, would seem (to me) to strengthen the materialist thesis. It says that identically prepared physical systems result in identical persons.
  4. Mar 21, 2003 #3
    That bit you mentioned is the materialist ASSUMPTION. If identical physical systems result in identical persons, then you are identical to your clones. Doesn't it seem weird to say that you are the same person as your clones - ie that you, an individual person, can exist in different places at the same time?

    So the anti-materialist argument goes: perhaps there's something wrong with the assumption? And I say: not necessarily. (see my original post above)

    And may I add - when I say you are identical to your clones, it doesn't mean necessarily that you are the 'same' person. You are just 'indistinguishable' from your clones. Perhaps it's a case of behaviourally identical clones having different 'essences'/'souls' (says the anti-materialist)?
    Last edited: Mar 21, 2003
  5. Mar 21, 2003 #4
    This scenario defies Quantum Mechanics. Sorry, but statistically you just cannot make an exact duplicate of yourself before the universe as we know it ceases to exist. If you could use Quantum teleportation to make a copy of yourself it would have statistically significant deviations upon arrival.

    In addition, Relativity implies that mass-energy and spacetime are intimately connected. Just as no two things are exactly alike, no two points in space are either. It is just impossible to have some place without also having some thing and vice versa.

    Assuming then that you do teleport a copy of yourself it would not be exactly the same at all. For the sake of argument, assuming it is superficially humanly impossible to tell any difference, it still doesn't seem weird to me. Every snow flake has at least one "identical" copy somewhere. Supposidly every person on the planet has someone else somewhere that looks strikingly like them.

    All this points out to me is that we are all similar and different at the same time. Perhaps that is the real paradox.
  6. Mar 21, 2003 #5
    I made a mention about the technical (or theoretical) difficulty of making an exact duplicate. Also, would those statistically significant deviations matter much? If each cell is in the right place, would the function of the person change much if the electrons aren't in exactly the same place? (differences on such a scale would quickly restore to physiological equilibrium anyway) If you consider yourself to be the same 'self' right now as the one an hour ago, you must consider your clone to be the same as you (the quantum differences are much smaller compared to the physiological differences)

    Perhaps I am missing your point, but of course no 2 things are EXACTLY alike for the very fact that they occupy different spaces!

    The weirdness is in the supposed 'splitting' of consciousness, not the behavioural identity. Before the procedure, there's only one person/consciousness. But the procedure seems to be making multiple copies of the same consciousness. Imagine going through the procedure where your original body will be destroyed and 2 new copies will be made. Will you survive? If so, do you survive as only one, or two persons? Won't it be a bit weird, intuitively speaking, to survive as two people when you think about the apparent continuity of conscious experience?
  7. Mar 21, 2003 #6
    I don't know about you, but my experience of consciousness is just as discontinuous as continuous. I'm a bear to wake up sometimes and I seldom remember my dreams. One minute I'm awake and the next its another day altogether.

    In addition, Quantum teleportation does not "split" your consciousness, at least, as far as anyone knows. It replicates it and exactly how good a copy it can make, if any, is still a matter of speculation.

    Consciousness is the only weirdness I see in this discussion. Because most people's definitions of the word are so vague, you could go in endless circles thinking about the subject. Much as little children when contemplating infinity. Careful, or you might make yourself so dizzy you'll throw up. :0)
    Last edited: Mar 21, 2003
  8. Mar 21, 2003 #7

    Tom Mattson

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    OK, I read too much into the story. I thought the copy would automatically result in an identical person.

    It doesn't seem any wierder to me than to say that two floppy disks with the same information coded on them are in two different places at the same time.

    I agree with your solution.
  9. Mar 21, 2003 #8


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    At first, I too was a little confused by the question. But I think I get it, now. Tom, the important point here is in your use of the phrase "two floppy disks".

    If I step into a Teleporter here, and all information regarding my physical existence is transmitted to a destination somewhere in the Andromeda galaxy and reassembled, it could be said that that which now occupies the destination point is "me". I think what makes this an argument for non-materialism is the concept of "identity", because if the material "me" that steps into the teleporter is not destroyed, then that which arrives in Andromeda cannot be "me", since "I" am still here on earth. What arrives in Andromeda is only a copy or duplicate of me.

    So, says the non materialist, what we now have is something that is identical in every measurable way (every way that is knowable my scientific means), yet undeniably not the original. So, although all the material information is identical, we will have separate identities. I will be "me", and he will be "he" (teehee, teehee!).
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