When you arrive you're teleported to the surface of a planet. Unlike the transporter on Star Trek, however, in the process we're describing your body disintegrates on the Enterprise and is instantly reassembled out of completely different atoms on the surface of the planet.
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| Star Trek Teleporter |
Assume that the reassembled person has all the memories and knowledge that you did before being disintegrated. Is the reassembled person (RP) really you?
If materialism is true, it's hard to see how it could be since RP is made of completely different material stuff than you were.
If you say that the material stuff has the same form as it did before being disintegrated you're adopting a kind of Aristotelian/Thomist view of the soul, which materialists would find offensive.
If you say that you have a mind that survives the disintegration process then you're again renouncing materialism because you're positing the existence of an immaterial substance, i.e. a mind or soul, that's an essential part of your being.
So, what is it that makes RP the same person as you? Memories? If it's memories how many of your memories must you retain in order for RP to be you? Every day we lose many of our memories. Can you remember word-for-word a conversation you had yesterday or the day before? Probably not.
Nor can you remember much about yourself from ten years ago, so what percentage of your memories must you retain for RP to be you? If memories give us our personal identity then an amnesiac or an Alzheimer's sufferer would be a different person than before losing his or her memory.
Besides, it's not clear in any case that our memories are material or physical. Perhaps the brain stores electrons or chemicals on neurons which somehow get translated into a recollection, but those electrons aren't the memory itself any more than an inflamed nerve is identical to the sensation of pain.
When you remember your mother's face you have an image of her face, but the image is not electrons or chemicals in neurons. It's arguably something immaterial.
Perhaps you might say that you and RP are the same person because the genetic code inscribed on your DNA would be the same in both of you, but identical DNA would only mean that RP was a clone of you. It doesn't mean that RP would actually be you.
It seems that the materialist has to assume that you have ceased to exist and that RP is not you but a new person similar to you. Either that or they need to acknowledge that materialism needs to be rejiggered somehow.
Maybe, though, there's another option. Maybe materialism is just false and there's something immaterial about us that makes us who we are. Perhaps we have a soul that bestows upon us our identity and which is unaffected by the teleporter.
If so, you and RP might well be the same person.