The game told me I was a psychological reductionist, for whom only psychological continuity is important. Fair enough, but it then berated me for taking the spaceship rather than the teleporter. Um, what? Whatever appears at the other end of the teleporter is not me, I'm dead and my consciousness extinct, so why the tut-tuting?
I took Space Ship + silicon rather than virus. I thought the tut-tutting was pretty well explained:
> But there is a tension. In allowing your brain and body to be replaced by synthetic parts, you seemed to be accepting that psychological continuity is what matters, not bodily continuity. But if this is the case, why did you risk the spacecraft instead of taking the teletransporter? You ended up allowing your body to be replaced anyway, so why did you decide to risk everything on the spacecraft instead of just giving up your original body there and then?
The question being posed is "what is the difference between replacing all of your cells, vs all of your neurons over time?".
My logic was that my molecules are being replaced over time, so is that so different than my neurons being replaced over time, whereas a wholesale replacement of my body felt like a break in continuity. I'm no philosopher though :)
This is a thought experiment know as the Ship of Theseus[0]. I never thought of it in terms of replacing molecules in a human body, it certainly spices things up.
Yes it is like the difference between rolling a wheel from point a to b and picking it up and carrying it over. Life is the rolling. Once the rubber leaves the road it's rip.
Exactly the same for me, this is incorrect, though not for the reason you point out. The person at the other side of the teleporter is you. One copy of myself dies whereas another copy of myself lives. Both copies are identical, so both of them are me. So in my opinion this should count as a half death.
Otherwise, if the argument was that the destroyed copy doesn't count because I can "feel no continuity", then any quick and sudden death wouldn't count as a death. That would be absurd. If, on the other hand, you believe the teleporter makes a copy of yourself that isn't you, then you're simply not a genuine psychological reductionist.
In my opinion, it makes sense to avoid a 1/2 death by taking a 1/2 chance of staying 100% alive. If it doesn't bother you to die at the teleporter, then any sudden, quick death shouldn't bother you either, which goes against the explicit instruction to ensure survival. This is also true in general without the instruction. If a perfect copy was made of someone, it would be rational for both copies to desire to survive.
>Whatever appears at the other end of the teleporter is not me, I'm dead and my consciousness extinct, so why the tut-tuting?
If you think you died when you entered the teletransporter, then you either think bodily continuity or an immaterial soul is relevant. All that matters for psychological continuity is that the person has the same memories, personality, etc. as you.
This isn't my first rodeo down this particular philosophical culdesac, but what I've always wondered is - why do you have to destroy the source person in the teleporter? If you don't, then there's still an exact replica of you at the destination. What if the copy comes back to Earth via spaceship and shoots you? The end result is the same, but it sure looks like you're dead.
If you don't destroy the original body, then both copies have an equal claim to being "you" right after the teleportation, since both are psychologically continuous with the person who existed moments before. Over time, they will have different experiences and different memories and gradually become different people.
>What if the copy comes back to Earth via spaceship and shoots you? The end result is the same, but it sure looks like you're dead.
The end result is very different because the memories of the surviving copy will be very different. He will remember killing a copy of himself, which by that point is more like a close family member than an identical self.
Not sure what you mean. Do you mean would it be ethical to kill one of them? In my opinion, once two people exist, it would be unethical to kill either of them.
Then the transporter should never destroy the source person, right? That's my whole problem with the idea. Imagine that the technology to destroy the person at the source didn't exist (this is fantasy tech for the purposes of philosophical naval-gazing, afterall), and the machine simply shot you to death after completing the upload to the source.
According to the psychological continuity theory, it shouldn't matter what happens to the original body, as long as the experience is the same. Whether your original body is vaporized or shot, you experience entering the teleporter on Earth and emerging from the teleporter on Mars a moment later. You weren't killed, you were transferred to a different body.
Of course, you don't have to agree with the premise that personal identity is psychological continuity. But I think there are other thought experiments that make the bodily continuity theory counter-intuitive. What if my brain was transplanted in such a way that I experienced going to sleep in my body and waking up in someone else's body, with my memory and personality otherwise unchanged? The bodily continuity theory says I would be a different person, but my intuition is that I would still be the same person, just with a different outward appearance.
Speaking as a potential original body, screw that - I'm not setting foot in a teleporter. But if other people want to try it, that's interesting too. Of course, it's hardly a new problem/paradox; if you haven't seen Christopher Nolan's "The Prestige", it's worth a watch and this is a plot point. And obviously the thought experiment goes back much farther. I'd hardly be surprised if some Greek dudes were arguing about it before the birth of Christ.
Yeah, I'm generally not an early adopter of technology -- I would probably let a few million people try it out before I put my own body in it. The Prestige is excellent. Christopher Nolan has a talent for taking a philosophical concept and turning it into a great action/thriller movie.
Not a philosophical point, but potentially a physical one.
The quantum no-cloning theorem says that it's physically imposible to make any copy of a quantum state, for example all of the state which comprises your body. But it is possible to transfer quantum state from one form to another. This is of course only true of the physical world if the assumptions of the no-cloning theorem are true. Let's assume they are.
Teleportation of your body including whatever quantum state you might consider important therefore must involves a process that appears, to an observer outside, to dissolve the state at one end simultaneous with recreating it at the other end. For some fuzzy definition of simultaneous; this is quantum state after all, and time is subject to the uncertainty principle just like position and momentum famously are.
The information transfer is analogous to transferring a box which the teleporter cannot look inside. You know it can't look as looking destroys the delicate contents. The teleporter cannot use non-quantum information to encode the contents. But the no-cloning theorem doesn't rule out translating quantum states to different forms, such as complex molecular states to light pulses and back. This is difficult, after all modest size quantum computers are difficult to build, maybe even impossible in practice, and they are much simpler than quantum teleportation of interesting size objects.
Squint a bit, and from a certain point of view, this is not destroying your body while creating a copy. It is an exotic form of physical movement, a bit like traversing a wormhole with your body retaining its integrity during the movement, except the wormwhole geometry is not spatial as we normally think of wormholes, it is instead a kind of complex state transformation analogous to geometry. But to you, it might appear that the universe around you is dissolved by the teleporter, then a new location of the universe is reformed around you, then you step out. No loss of physical continuity.
If you do take the teleporter it mentions that as well:
> Your three choices show that this is what you see as central to your sense of self, not any attachment to a particular substance, be it your body, brain or soul. However, some would say that you have not survived at all, but fallen foul of a terrible error. In the teletransporter case, for example, was it really you that travelled to Mars or is it more correct to say that a clone or copy of you was made on Mars, while you were destroyed?
because you've suddenly switched to a sort of dualism. If you are a psychological reductionist (from some of your other choices, like say using the artificial brain parts), then you assume that minds are what brains do. There is no consciousness separate from your brain, your brain produces your consciousness. So all that matters for you to be alive is for some brain to be around that produces the same mental states you have. There could even be multiple of you!
But if you hop on the spaceship you threaten that continuity for the sake of your body. In that case you treat your consciousness as distinct from your body and are afraid of 'losing' it or not being able to transfer it should that particular body die. So you don't just care about your psychological state any more, you think your particular body 'carries' your mind around. That's a contradiction.
What is the difference between slowly replacing your cells a few at a time through biological processes, and instantly replacing all of your cells through the teleporter?
In both cases, an older version of you is "extinct", meanwhile, the latest version of you does not have any recollection of becoming extinct.
Imagine the "destroy the original" part of the teleportation fails. Is your consciousness still in your original body or on Mars? Certainly, still in your original body.
Now the doc is replacing parts of your brain with silicon. It's posited that it makes no difference to your mind. Because of that, is your consciousness still in your body? Very probably.
> Imagine the "destroy the original" part of the teleportation fails. Is your consciousness still in your original body or on Mars? Certainly, still in your original body.
How do you reach this conclusion? The only conclusion I can reach is that an identical consciousness is certainly in both bodies. (And as soon as both bodies are making new memories, you have a "fork", where the two persons stop being identical)
How would that work? Would you control both bodies, see through both set of eyes, think with both brains? How would the ineffable quality that makes you feel like you are you get transported to Mars? I don't think that's a tenable possibility.
There is no single "you" in this scenario, there are two distinct persons. One experiences being transported to Mars, the other experiences the transporter failing and them being stuck on Earth.
I think we're talking at cross purposes. Me, the body I inhabit, is still on Earth. The person on Mars, who likely also has a consciousness, and is for the whole world exactly the same as me, is still not me, but someone else, because I am on Earth, and I can't be in both bodies.
So I will not take the teleporter any more than I will shoot myself.
> and is for the whole world exactly the same as me, is still not me
If both are identical I don't see why both aren't equally me.
> because I am on Earth, and I can't be in both bodies.
Why must there be a single continuation of "me"? I wouldn't necessarily consider this true even under current medical technology - we can split the brain in two and have two parts that do not directly communicate.
What if the process is symmetrical (one body in, some kind of mitosis occurs, two bodies out at equal distance)? Does one get assigned "the real me" at random? If both have the same memories/personality/train-of-thought and experience the process as continuous, why not both?
I can't seem to be able to reply to your comment below, but thanks for the clear illustration. I don't disagree with PM PM; I don't believe in souls. What I do believe in is that there is a quality of consciousness that is linked to the PM - what makes you see through your own eyes and not others. That quality does not seem transferable, in that bodily possession is not a thing.
If you posit that teleportation is equivalent to spaceship, and that a single consciousness cannot inhabit two bodies, then what is your hypothesis about the more-or-less instant transfer of that quality to a remote planet's newly created clone?
Consider IM to be any immaterial "self" that you believe wouldn't be included in the clone - doesn't have to be a soul as various religions may conceptualize.
> and that a single consciousness cannot inhabit two bodies
I believe there could be two bodies with identical personalities/memories/train-of-thought/etc. (whatever we label as consciousness) at some instant, but they would diverge due to different environments and not have any kind of special link between them.
> what is your hypothesis about the more-or-less instant transfer of that quality to a remote planet's newly created clone?
In my view it's just included in the clone - there's nothing extra that hasn't been cloned that needs to be transferred afterwards. If you totally clone an ocean, it has the same waves.
But we are not talking about mitosis, so we don't need to go there. We are taking about a machine that assembles atoms on a remote planet. None of the atoms come from your current body. What magic would transfer your consciousness into this clone?
> But we are not talking about mitosis, so we don't need to go there
I'm probing to get a better understanding of your belief system. How does it hold up under symmetrical cloning?
> What magic would transfer your consciousness into this clone?
I'll label:
* PM: Physiological "me" - personality, memories, train of thought, currently instantiated as a brain
* IM: "Immaterial" "me" - a "soul", impacted by the PM. May impact the PM or just be an observer (depending on variant of dualism)
From what I understand, you believe there's an IM controlling a PM, and the IM is a different kind of stuff that would not be cloned. The IM generally follows the same PM, but could be "shaken off" from too-large changes. On cloning of PM you think this happens (at the instant of cloning):
IM New soul
| |
PM PM
You ask "Would you control both bodies, see through both set of eyes" because you thought sunaurus is proposing this happens:
IM
/ \
PM PM
Whereas I (and I think sunaurus) don't believe in an IM. We think two identical PMs really are identical persons, including whatever we'd call consciousness:
PM PM
Others may believe that IMs do exist but supervene on the PM (so identical PM has identical IM arising from it):
> What is the difference between slowly replacing your cells a few at a time through biological processes, and instantly replacing all of your cells through the teleporter?
If you believe that you die when your cells are replaced (because you are in the old cells and thus can't be in the replacement), then I understand your point of view. But if you're saying that slowly replacing you is different than quickly replacing you, then I would be super curious to hear the logic for this! (This is a sincere comment, I am not seeing the logic myself and would really like to understand it)
So, the slow replacement preserves consciousness. Why, who knows, but it happens to us already every day, so we can take it as granted. If it didn't, we'd be someone different every day, with false memories, and while it's not impossible there's not really many places reason can take us from there.
The problem with the teleportation is not even that it's a quick replacement... it's that it's not a replacement at all. You're building a clone somewhere else, and destroying the original. You could build 50 clones at the same time on 50 planets if you wanted - and of course none of them would be you, there's zero chance you're preserved. So, you're dead, even if to the rest of the world it makes no difference.
What you're saying seems like a clear contradiction to me.
In your first paragraph, you say that we can take for granted that when an original is destroyed, having a replacement will preserve consciousness. Then, in your second paragraph, you say the opposite - that destroying an original would NOT preserve consciousness, even if there exists a replacement.
There must be some key assumption which lets you not see this as a contradiction. Maybe you believe that there is something extra-cellular which wouldn't get replicated in a teleporter?
I'm saying replacing a neuron or cell at a time within a quadrillion of them empirically leads to continued consciousness, and that assembling a quadrillion cells on a remote planet with no material connection whatsoever with the original body is a very different thing. You want to hide both cases behind the same word. I don't see why you think that's valid.
I think it comes down to how that replacement happens. If you keep adding new chips or whatever it is as your old cells die or get altered by the virus, that's one thing. However, if you download your conscience to silicon and have that replace your brain, that's entirely different. I'm unsure which one it was in that question.
I viewed those questions as a play on the Ship of Theseus.
If the ship is completely destroyed and a perfect replica rebuilt elsewhere, is it the same ship? Almost certainly not.
If the ship is slowly replaced over time, is it the same ship? As a matter of form or psychological continuity as posited in the question, almost certainly.
Why do you think those two questions have different answers? For me, the only logical option is that both questions must have the same answer (regardless of what your answer is).
I don't follow your logic. How would constructing a new ship from new materials ever count as being the same as the original ship?
At least in the Ship of Theseus paradox, there is the case where you take the old replaced parts and construct a ship from those parts - which is an interesting question, is it the original ship? In this case, the only thing consistent about the ship is the design. Take mass manufactured goods then - are they the same article because the have the same materials?
> How would constructing a new ship from new materials ever count as being the same as the original ship?
If it's a perfect replica (as you said in your original comment) then by what parameters is it different from the original ship? Sure, cooordinates might be different, but cooridnates can change. If the exact replica switches places with the original, then even that difference would disappear.
By the way, I am strictly speaking about this topic in the context of the thread we are in. If a replica is built according to exact blueprints of a snapshot of the original (and assuming no mistakes are made), then why would the result be any different than just replacing one part on the original with an replica part made according to exact blueprints of a snapshot of the original part?
> What is the difference between slowly replacing [...] and instantly replacing [...]
Not to be obtuse, but... the speed.
Really this is a shortcoming of the thought experiment. Progressive replacement is subjectively more continuous than complete replacement. A better thought experiment would be to feed it out something like:
* What if we replaced every atom of you body progressively over 24 hours?
* What if we replaced every atom of your body suddenly all at once?
* What if we replaced every atom of your body, but delayed by 1s?
* What if we replaced every atom of your body, but delayed by 1 day?
* What if we replaced every atom of your body suddenly all at once, but moved about 1mm?
* *What if we replaced every atom of your body suddenly all at once, but a day later and moved by thousands of miles?"
What is the practical difference, though? From the point of view of the entity whose atoms have been replaced, I don't think that the speed of replacement has any noticeable effect. And the previous versions are all "extinct" regardless of the speed, so from the point of view of any previous versions, the situation doesn't change either.
We replace the cells in our body every few months, correct? The gradual replacement is key to the continuity. I'd be ok replacing every one of my neurons one at a time but not to upload my brain to a computer and then kill myself. To an outside observer the result may be the same, but not something I'd be comfortable with. I know my consciousness is an illusion and I probably "die" every time I go into deep sleep but the key is to uphold the illusion, otherwise why go on?
But why would the feeling of continuity be broken by an instant replacement?
In both cases (gradual and instant replacement), at any given moment, there exists only one entity with your consciousness and self of sense and continuous memories leading up to that moment.
I think my point is, maybe there's no such thing as continuity of experience (since we sleep every day) and consciousness itself may be an illusion. With an instant replacement, and also with a large distances, it makes it clear this is not me any longer, but if I replace my neurons gradually with digital components it's essentially equivalent to what is already happening with my brain cells, so it doesn't break the illusion. My identity and consciousness is an illusion and I just don't want to break it. I know that is contradictory and makes no sense, but that's the reason I would not use the transporter.
It's not a replacement, a collection of atoms is assembled on a remote planet. And it needs not be a single entity, as the thought experiment with the failure to destroy the original body shows.
I took the same path and got the same tut-tutting. The clear issue is being uncomfortable with immediate replacement vs incremental. I agree it’s illogical, but I’m okay with being illogical on this very hypothetical question.
For me, personally, it comes down to the risk of copies. While both scenarios make copies possible it seems less likely in the case where you’re simply replacing parts of my brain. I cannot imagine copies not being made in the teletransportation scenario.
It seems to me that it's only illogical in retrospect. I don't know that there's body and brain eating viruses ravaging Mars, or that souls have to be frozen to die, and I have to make a choice about this, or what any of that means. I make that decision with only the knowledge that I have to take a ticket to Mars and that my goal, throughout, is to "stay alive."
That’s because the author’s concept of “psychological continuity” is looser - “your mind’s rough configuration exists somewhere in the universe some time in the future“, which is different from how you and I define it.
Perhaps the ”strict psychological continuity” could be called “psychological+spatiotemporal continuity”, but apparently the author considers the spatiotemporal part to be a component of “strict bodily continuity” and nothing else. If you value temporal continuity independently of bodily continuity, the third question becomes a choice between “dead and soul-destroyed” or “dead but reincarnated”, which is clearly not the author’s intent.
If you were an AI on a computer, and you had a choice of either being copied to a fresh computer with 100% reliability, or having your computer packed up and shipped with a 50% chance of being destroying in transit, which would you pick?
