Hacker News Reader

Comment by sodiumphosphate | Hacker News Reader

While it does make for some entertaining fiction, and may provide some benefits to the living, I do not believe that 'uploading' is a desirable experience.

In fact, I don't believe that one can experience it at all. Imagine the procedure (for a conscious person): your brain is connected to a computer interface and a copy of your mind is taken. Great. Now there is a digital copy of your mind. So what? You still get to die.

Consciousness is mortally bound to the physical body, and will die along with it regardless of how many mental copies are made.

I much prefer the idea of human metamorphosis. I want to inject nanorobots into my body which will transform it gradually, cell by cell into an improved synthetic one. In this way, immortality and superhumanity can be achieved without loss of continuity. I imagine the experience would be one of waking up a little better (stronger, smarter, etc.) every morning until the cells are all upgraded.

I don't read enough these days because of chronic eyestrain, but if you are aware of anything dealing with this concept of human metamorphosis, fiction or otherwise, I would appreciate a link. It's something I would like to read about (if it's even been dealt with), someday when I have time (and don't have a headache).

View on HN

I agree that human metamorphosis is extremely interesting, but this line I really don't get:

> Consciousness is mortally bound to the physical body, and will die along with it regardless of how many mental copies are made.

I don't understand how you can put out a statement like that, like it's taken for granted or something. It's far from granted, and I've never heard of something remotely approaching a proof for this type of assertion. To my mind it's the same kind of reasoning which proved we would never fly, nor go to space.

It's an open problem. Please keep it that way until we know more.

We don't have the proper tools to understand consciousness in a scientific way yet (consider the extremely limitations of EEG and MRI) For those interested in this philosophical question, there's an area called Philosophy of Mind [0] which deals with this and related questions.

0: http://en.wikipedia.org/wiki/Philosophy_of_mind

Granted that consciousness is not fully understood, can we not agree that it is entirely manifest in the brain? I mean, you don't believe that human consciousness somehow survives the body after brain death, do you?

Even if the cloned memories could be streamed from your brain into a running simulation, allowing a memory of crossing the threshold from the physical world to the digital one to be created in the simulation, the 'patient' will not have this experience. The patient will still have to experience death.

Going further, let's imagine that we want it really, really badly. Let's destroy each neuron immediately after taking it's state and pushing it into the stream, so that the whole process of uploading and death are completely synchronized and nothing of the patient's consciousness remains afterward.

I'm sorry, but I still do not think that the patient will experience being uploaded into a computer. It will only experience having it's brain fried until death. For the clone, the memory might just be glorious, like some Hollywood special effect sequence, but personally I find this wholly unsatisfying.

I'm not saying it shouldn't be done, either. I'm only saying that I suspect some people may have the wrong perspective about it. If you sign up for this procedure, you are not signing up for immortality, but merely to donate a copy of your memories to whomever is running the simulation.

You would be like an organ donor, but instead of saving a life, you'd be feeding your mind to the new Zombie Second Life.

It would not benefit you, but it might benefit someone else.

As for me, I'm a selfish, arrogant bastard with a desire for physical immortality and superhuman capabilities.

Lets go over this carefully as the concepts are slippery.

Lack of continuous experience of an event does not mean you died, it is merely memory loss.

Assuming the very reasonable theory that consciousness is classical and emergent from the network structure and interactions of neurons and glia then it should be possible to encode this consciousness on a turing machine. If we go a step further and replace certain collections of simulated cells with black boxes that behave the same way given an isomorphic set of inputs then we can have consciousness even more cheaply.

Your idea is not necessarily more grounded. Assumptions you make are: the substrate does not matter as long as it is not digital, you assume the replacement material will not itself have effects that result in vastly divergent actions in the long run. Yet the perturbations a neuron suffers will differ from those of nanodiamodons, will this be significant? You also take for granted the new replacement brain will not allow a very large viewpoint shift due to the new complexities and speeds of thought possible. That some invariance of self remains from morphism to morphism. That there is more resemblance between you and the the final being than you and a lemur like ancestor.

It is likely that the beings of the future will have far more sophisticated definitions of self and identity.

I personally think that physical bodies will give way to digital minds and its only a matter of time. Whether linear time or log time I can't say. But physical bodies are resource hogs. Progress is energy intensive and so is ever more complex thinking. Imagine a being whose memory is so dense that its thoughts have a gravitational pull of their own and its mind risks collapsing into a blackhole... Eventually theres going to be a lot of pressure to compress thinking beings and squeeze as much thinking capacity from matter as efficiently as possible.

You not only misstate my assumptions, but seem to miss my point entirely.

Here is my point: the original human will not experience continuity, therefore it's instinct for self-preservation will not be satisfied. The best it can hope for is to take comfort in knowing that a copy will survive. Personally, this does not comfort me.

I don't doubt the possibility of a very high fidelity copy and supporting simulation, for all intents and purposes. I also think there may be sound reasons to pursue it. But I don't think it will benefit those who are copied, beyond any positive thoughts and feelings it may give them before they die.

Being selfish and programmed for self-preservation, I desire physical immortality instead. I have no interest in donating a copy of my memories to a simulation project.

I hope this clears it up; my interest is quickly waning, and I have work to do.

Which one is the original? Both have the same memories; I think they both have a good claim to that identity.

The claim to the identity is not the issue, the issue is that the person who got copied will die and experience that death.

The existence of a copy does not make the original person to resucitate or otherwise keep perceiving and thinking.

To express it in a bad analogy: you can have a bit by bit backup copy of a harddrive, but when a power surge burns the CPU and the disk, you have to throw both away. You can buy a new CPU and place the backup, but the hardware is different, there is a shutdown moment, and when you power back, the continuity is lost, it's a different entity what gets booted up.

To preserve the consciousness of a person, between the "hardware change" I see no other option to the existence of something like a central repository of consciousness outside both the body and the computer hosting the simulation that gets automatically attached to a particular set of memories/perceptions/experiences (and whatever else defines a consciousness), so when you die, it stores your consciousness and when the simulation is booted up, the continuity is triggered. I find that far fetched.

If consciousness is a very simple emergent phenomenon, is the distinction between one instance and the other still interesting?

In abstract, philosophical terms, it might not be. Even in policy terms it's probably not (other than it might be cheaper to store people in SANs.) In practical, day to day terms, of course it is! My own instance of self doesn't want to cease to exist.

I'm not sure. Your body changes all the time. Your mind is always running on different hardware than it was just a few moments before. The changes are just small at each step.

>I'm sorry, but I still do not think that the patient will experience being uploaded into a computer.

If the copy/delete process was (perceptually, hence effectively) instantaneous, what is the difference?

Lets say your biological body was going to die, in a day. But you have the option of being perfectly copied into a new biological body now, with the current body being instantly destroyed. Would you take the option? I think I would.

Whats the problem with that? How is it any different than what happens to your body on a day-to-day basis, now, anyway?

I don't see the problem, when we put it in these terms.

The question goes to consciousness, and our special identification with our own perspective.

We can posit that our "consciousness", as we experience it, resides entirely in our physical bodies, and that exact duplication of some subset of those bodies can create a consciousness exactly the same as ours. So any observer outside our body will be indifferent to whether they deal with the original or the copy.

But unless there is some communication between the two consciousnesses, you will experience the copy as something outside yourself. You won't have its memories after the moment of duplication, and you won't experience continuation. If your body dies, your consciousness dies. So while the world can have endless copies of you, and perhaps each copy feels like you, you still experience mortality. Your consciousness ends with the particular physical construct sustaining it.

At least, in the posited model.

The gholas of Dune are aware of this, and don't imagine themselves immortal though they know copies of themselves will be made after their departure.

>Whats the problem with that? How is it any different than what happens to your body on a day-to-day basis, now, anyway?

Or how is it different that going into sleep and waking up?

Going to sleep does not cause the brain to actually power off. It's still running, your consciousness is just different. You still wake up from loud noises and light, and external stimuli can still influence your dreams.

>Going to sleep does not cause the brain to actually power off. It's still running, your consciousness is just different. You still wake up from loud noises and light, and external stimuli can still influence your dreams.

Anesthesia, then, or fainting. You cannot wake up from loud noises, and you have no consciousness.

One can also image a transfer process that is just like what naturally happens with regular body cells changing every 7 years or so.

E.g your brain is slowly, over a period of years, replaced cell by cell with new compatible neurons. One by one, your old neurons are replaced with the new, designed ones.

Those can read the state of the neuron they exchange AND exchange signals with your regular neurons, so before and after one is replaced, your brain is still functioning normally. No "power off" phase.

How about that?

That is what the person above describes when they say they want to be injected with nano-bots to be converted. And that would, I believe, give a seamless transition with no break in the stream of consciousness.

However this is completely different from the concept of mind uploading where your brain is scanned and simulated separately.

It's he same problem as teleportation (star trek teleportation specifically)

They scan you, break you down, then transmit and create a new you. Now if you re-order this a little. Scan, transmit, create and then break down the original. There are two of you, then the original is killed. This shows that during the original process the first is scanned and killed, then a new person created. This is exactly how mind uploading would work in terms of continuity for the person being uploaded. (It's also why I would never ever use a teleporter.)

This is exactly what mind uploading is, they scan you and upload you. Creating a new you. Then you die and the other you lives on. This is very clearly shown if you scanned and activated the copy before the first person died. Are you trying to imply that you would suddenly, as a single entity, be experiencing two perspectives at once? Because that just wouldn't be possible.

It is technically immortality for your memories, but not the specific physical instance of you.

> I still do not think that the patient will experience being uploaded into a computer

Creating a copy is like having a Siamese twin you didn't know about, because it was sharing 100% of your body and mind. But with the copy you are split apart for the first time.

If you are being uploaded at the time of the split, then one of you experiences the seamless first-person transformation into digital form. The other you stays biologic and dies, immediately or eventually depending on the procedure.

The irresistible urge is to mope that "you" are the biologic one, the one that dies. But this isn't true, you really are both. The one that became digital is you in every sense, it woke up in your shoes, it took your date to the prom, it has your personality, it will make the decision you would make going forward.

If you think the copy is inferior or inconsequential by virtue of not being the original, then consider what if we right now are all copies? Would our lives and first-person experiences be less genuine and less valuable if it was revealed there the true original versions of us existed elsewhere? In an upload scenario the copy is you.

But why bother? Unless you really think the world is worse off without you and your contributions, why would you participate in a service like this? It's not going to do you any good or let you live a day longer. Your copy will go on having a perfectly happy life being the new you, but why should any of us be excited about that?

You're discounting the experience of the copy and identifying solely with the original biological human. Instead you have to really internalize that both experiences are equally yours.

That said, I wouldn't get excited about it. Uploading is a bald afterlife myth with the same capacity to beguile as the religious versions. Better to focus on the here and now.

I may as well internalize that Warren Buffett's experiences are equally mine, or a strain of bacteria. If we're not defining "self" through any real continuity and instead just making it an arbitrary label, there's no reason everybody can't be me. It becomes a bit meaningless.

Sleep and anesthesia break continuity, as has be reported elsewhere in this thread, so self is not about moment to moment continuity.

The reason your copy is equally you vs. Warren Buffet is that your copy shared every molecule in your body and every thought in your head for your entire life up until the moment of splitting off.

Let's imagine you run the simulation when you are still alive. Are both copies you? Wouldn't each copy believe it's a full consciousness and not half a consciousness?

Assume you do a regular (or even automatic and continuous) sync between the copies. Which copy would you prefer survived, if one of them were to die?

Both copies would claim to be you, and would have equal right to that claim. Yet each copy would be a fully conscious person and would immediately diverge into its own individual from the shared point on.

This of course sounds like a contradiction, both are you and both are individuals? That's because our language and concepts just don't have the muscle for this situation. "Both are you" is short-hand since the wold "you" becomes ill-defined or at least radically transformed. Consider Hofstadter's "twin world" concept from his "I am a Strange Loop" for how a single "individual" could really be made up of multiple individuals.

From an objective point of a view it's much better if the digital version survives, because we're assuming the biological original has a shorter life span.

You avoided the question, what would you prefer? There would exist two (or n) instances of you, with a shared history, but no shared present. Maybe you posit the question is moot because the concept of you dilutes at the point where a copy is made? I can't imagine how it would dilute enough for the physical you change its self-preservation instinct, though.

On the other hand, I'm not so sure that the digital version is preferrable, there are lots of maladies that would be trivial on digital versions, for example destroying the being, controlling it and altering in any way. All that stuff is (so far) harder on the biological world.

(PS: Thanks for the Hofstadter pointer, I stopped following him at The Mind's I)

I don't like "would you kill X or Y" questions. For one details matter, and we have no details. For two it's just impossible to say sitting here in my comfy chair how I would react in some dire life-or-death situation.

I think its possible to contend that our physical body is sufficient in providing a framework for our human consciousness to emerge, but it may not be necessary in maintaining it.

Think of a stroke patient. Often stroke patients lose their memories / personality temporarily, but then regain it some time later. The injured portion of the brain heals in some respect, but the memories/neural functions of the injured area often move / reorganize to a different location in the brain (which is why sometimes a stroke patient can feel sensation in say their hand when someone touches their face).

I think this comes to show that our consciousness/memories/etc are not necessarily tied to a specific source of physical matter, as even the brain can reorganize the "coded" functions to different areas inside it.

> Granted that consciousness is not fully understood, can we not agree that it is entirely manifest in the brain?

I don't think we can agree on that. There certainly are many claims of consciousness existing beyond the human body. For example, see a "Unified Field" of consciousness.

> I mean, you don't believe that human consciousness somehow survives the body after brain death, do you?

Literally billions of people believe it does (see: pretty much all major religions). Maybe human consciousness doesn't survive brain death, but some other form of consciousness does?

> can we not agree that it is entirely manifest in the brain?

This is the old materialist vs idealist, monoist, dualist etc. debate in the philosophy of mind. It isn't as much of a slam dunk as you think it may be, and the gulf in opinion is broad and branches out into many tributaries.

Materialism is the belief that everything in the world, including mind, was material, but that has progressed into physicalism since late nineteenth century physics showed that not every force is made up of matter.

I used to be very interested in this topic and leaned towards the idealist argument of mind being made up of more than material, but I lost interest as the debate on both sides tends to spiral and involve religion and spirituality. But I still tend to believe that if we completely cloned a brain materially, we would still not have a mind, that it would be missing something.

My own conclusion is that we simply do not know, and that to me is more interesting than knowing as the pursuit is more rewarding than the end goal. There will always be open and unresolved questions in science and philosophy. We have yet to explain seemingly more simple phenomena such as gravity, so explaining the mind (or indeed altering it or cloning it) seems so far out of reach.

You express views and attitudes very similar to mine.

For people who find these things interesting, I recommend checking out the so called hard problem of consciousness

James Trefil, physicist - so they aren't all dopey philosophers ;) - notes that "it is the only major question in the sciences that we don't even know how to ask."

http://en.wikipedia.org/wiki/Hard_problem_of_consciousness

I believe that human consciousness is entirely manifest in the brain (and, of course, it's effected by other nerves elsewhere in the body). But moreover, I believe that brain is performing "normal computation," by which I mean Turing complete computation. Because of that, there is no real reason why the same computation responsible for human consciousness couldn't run equivalently on other Turing complete hardware.

I could imagine how a suficiently advanced machine could simulate one or more consciousnesses.

What I can't imagine is how you, the person sitting in front of the computer will somehow wake up in the computer. I can only see copies waking up. Even if you are dead. For the people who love you, having a copy would be great, but you will still be dead.

I can't believe I'm bringing this up, but the Arnold Schwarzenegger movie "The 6th Day" really matches my views on the subject, and also matches your views.

(Obvious spoilers for the movie)

In the movie Arnold is cloned, wakes up later, and goes about to find out what's going on. At one point he finds out HE is the clone! Back to our discussion. From the point of view of the Copy, the procedure was successful - the consciousnesses was transferred to the machine and the copy continues existence. From his POV he does wake up in the computer after the procedur. For you, though, it's a copy that wakes up. Perhaps your brain is destroyed during the upload process and you stop to exist. For the copy you (that is, him) continue to exist and avoid brain death. If a scientist asks you, "Was the upload successful?", you (the original) will answer "No". The copy you will answer "Yes".

For the digital copy to not notice the transition, there would probably have to be more going on—like a Matrix-esque simulation of the physical world or a realistic android to house the copy.

I do know that if you made a bunch of copies of me right now, I wouldn't expect to walk around seeing a superimposed image of my original self in Chicago, a copy walking around in New York, etc. I'd be totally disconnected from my copies, and that is reasonable proof to me that I should not expect to ever have a continuity of experience through a backup copy after my own death.

Are you making the unlikely assumption that you would actually be the original? More likely you'd black out during the brain scan and wake up as one of the copies. You have no good reason to simply assume that you are going to be the original process right after making that fork() call. How might your thoughts about this process change if you woke up as a copy?

If a scientist asks you, "Was the upload successful?", you (the original) will answer "No". The copy you will answer "Yes". That's my view, at least. Same answers for teleportation Star Trek style.

What is fascinating is how strongly and without proof many people believe the argument that "Consciousness is mortally bound to the physical body". If anything, this fixation seems like both an interesting study of the blind-spots of human mental process and as evidence that the situation is, in fact, rather unlikely.

This particular, uh, delusion, seems similar to the recurrent theme that an "intelligent" enough computer would/could "develop self-conscious" (whatever that is) and start "thinking for itself". Here, we have strong ideas about the properties of "self-consciousness", without, as you say, having a ghost of an idea of what it is.

this goes back to the ages old problem of, "In Star Trek, the transporter killed you every time" We have this almost social idea of Body Continuity. As long as there is the same body the entire time you are still you and still "alive". A scarier truth is that all it takes is a decent change to how you brain is structured (bullet, railroad spike, fork through the skull) and you can very suddenly for all intents and purposes be a different person, with the same or similar memories but essentially different patterns of behavior. Metamorphosis may not save you, it might kill the person you were just as if you made a copy and burned the original. Further down the rabbit hole, just how different is your brain now from and instant ago, and your brain versus your brain with the addition of a few ball bearings or other random matter. The person you were an instant ago is just as dead as the original who gets destroyed and you are the copy.

One example from history (railroad spike through the head in 1848); https://secure.wikimedia.org/wikipedia/en/wiki/Phineas_Gage

More recent example: http://www.bbc.co.uk/news/magazine-17703018

Ray Kurzweil has a nice point on this, calling human consciousness an "evolving pattern of information that persists through time."

> I want to inject nanorobots into my body which will transform it gradually, cell by cell into an improved synthetic one. In this way, immortality and superhumanity can be achieved without loss of continuity.

Just last night I thought about this and went to sleep in despair :>

If someone scans my brain, builds an artificial copy, instantly cuts out my brain and inserts the new one, I clearly die (because I got my brain/me cut out) and my copy lives on. From the outside, I'm the same, but the first me died.

So instead, I get my neurons replaced with artificial ones, one at a time. If I drink a few beers, brain cells die but I'm still conscious. So gradually replacing my neurons one by one should be no problem; there clearly is no loss of continuity, I'm still me.

But what's the difference? Let's assume one neuron is replaced every second. No problem, nice and gradual. What if it's one every millisecond, every picosecond? Should make no difference, because it's still one by one. But, the faster you do it, the more it approaches "instant". And instantly replacing all my brain cells is the same as replacing my whole brain. Thus, I'm dead and my copy lives on...

>If someone scans my brain, builds an artificial copy, instantly cuts out my brain and inserts the new one, I clearly die (because I got my brain/me cut out) and my copy lives on. From the outside, I'm the same, but the first me died.

If you look at the physics the right way, your brain is cut out and a copy inserted billions of times a second already.

Let's assume one neuron is replaced every second. No problem, nice and gradual. What if it's one every millisecond, every picosecond? Should make no difference, because it's still one by one.

It should make a difference how long it takes, though.

Assume that consciousness is a physical process. If new neurons take part in this process after the old ones die (so that we have continuity as part of normal "healing"), there must be some time scale over which those neurons become an effective part of the consciousness process.

At minimum, if consciousness is a "network effect", this would be on the order of the latency of inter-neuronal communications. If the cells are doing some processing which forms part of consciousness, the time scale would increase.

To throw out some wild numbers: neuronal latency seems to vary, but I found a number for visual-cortical neurons of about 80 ms. (http://redwood.berkeley.edu/bruno/npb261b/whitney-reading/kr...) And you can't replace more than a few cells at a time (I wonder what fraction?) if you want to avoid impairing consciousness during the process.

(This also doesn't include whatever the time is to make an effective copy of a given neuron and it's state; we're assuming instant perfect copying.)

You have an old car, and you want to renew it. If you buy it brand new and toss the old one, you are destroying the old one. If you keep changing pieces of it, testing them to see they work, and keep going until you have replaced the whole car, it's still the old car, just brand new.

There's not much difference at the end, except that you can consider that the second way of doing things will let you still use the old car, only it'll be new.

I largely agree that gradual replacement has the far better claim to preservation of identity. I would have hardly any desire to be uploaded any other way.

However, the car of Theseus example allows for a worrisome wrinkle. What if you kept all the old parts during the process you describe, and then after, you re-assembled them? Which car has the superior claim to being identical with the old car? I think it obvious that the reassembled old parts have the superior claim over the car produced by part-by-part substitution of new parts.

Not for me. For me that's a brand new old car.

Yes, it has all the parts of the old car, and only those pieces, but it was assembled anew from zero.

A more difficult dichotomy would be: what if we exchange parts between two cars until each one is the other one. That's hard to decide.

I find that first intuition odd. What if we alter to situation to not involve the new parts? Simply disassemble the old car parts and reassemble them, is that a brand new old-car?

Or how about we make all the new parts plastic so that no functioning "car" is produced by the gradual part-for-part substitution. We end up with two cars, one an all-plastic car model, and one consisting of all the old parts assembled and functioning. Which has the better claim to being the old car?

Yeah, part exchanges quickly leave me with even less salient intuitions about the proper use of old identity terms than these more "splitting" oriented cases. What should we say if a lion talked and all that.

> Great. Now there is a digital copy of your mind. So what? You still get to die.

You get to do both. The concept of "you" changes once there is a copy, see the Ship of Theseus [1]. Each post-you entity has a legitimate claim to being pre-you. The copy woke up that morning, ate your breakfeast, went to the uploading clinic, and went to sleep as a digital being. The copy has perfect continuity. The biological you on the other hand stayed biological and will die.

A gradual replacement doesn't change the fundamentals, the biological you has to die. The gradual replacement just makes for an unusual twilight, its mind commingled with an arising digital being.

[1] http://en.wikipedia.org/wiki/Ship_of_Theseus

I think that the experience of continuity is what makes these things entirely different.

It is the experience of continuity that satisfies my hard-wired desire for self-preservation.

You experience discontinuities in consciousness every day: when you sleep.

Why is it that we feel like the same person after we wake up from sleep, from anesthesia, or even a prolonged coma? You could go to sleep, have arbitrary operations done to the neurons in your brain while asleep, and presumably will awake into the "same body".

This thought experiment leads me to believe that the most important consideration for mind-uploading is to ensure that the original body dies/is killed before bringing the copy online.

Considering the metamorphosis idea, by the time your whole brain was replaced, piece by piece, by devices simulating its behavior, you became an upload - it's just that all of your data is running inside your head (or that this illusion is maintained by very low-latency links to your root-self running elsewhere).

Still, the moment you move its dataset to a new device and deactivate the original, aren't you killing the original?

From a body-centric point of view the original dies either way, whether neuron-by-neuron or all at once. From a consciousness point of view it's less clear. Firstly because we don't understand consciousness.

But if we believe consciousness is some subjective experience that results from the functioning brain or similar physical device, what can we say?

Think of a vinyl record and a digital music player. The vinyl record is playing along when it is stopped suddenly, the digital player is started at exactly the right time to produce no break in the song.

If you insist that you are the record player, then you die, you stopped. If you think that you are the song, it continued without missing a beat. Instead of an abrupt stop you can cross fade the record out and the digital one in over a few minutes. Does this make a difference?

That's one wonderful analogy! Thank you!

Greg Egan's short story Closer has people implanted with a device, a "jewel", that learns to mimic the behaviour of their brain - to the point where people actually choose to switch from their biological brain controlling their body to their jewel....

http://eidolon.net/?story=Closer&pagetitle=Closer&se...

Egan's story 'Learning to Be Me', available in the same collection as 'Closer' (Axiomatic), is also an exploration of this idea with relevance to sodiumphosphate's fear.

> Consciousness is mortally bound to the physical body, and will die along with it regardless of how many mental copies are made.

Why? Can you explain more? I would believe that you can be a fully functioning human living in a simulated reality if we ever managed to fully simulate the human brain..

However, since our brain modules are so messily coupled I don't know if we can easily "delete" memories and not impact anything else.

Unless you accept dualism (that there is some 'you' separate from the wetware in your head) you are always going to have this problem. A copy of 'you' would only sync with 'you' for an infinitesimal amount of time before you both diverged. The two 'yous' both have valid claim to everything before the Split but afterwards you are effectively two different people.

This is where the following thought experiment comes in:

Imagine science advances to the point where medical science can replace individual brain cells with perfect robot replicas. These robot cells interact with surrounding cells in exactly the same way as the real ones and can be initialized with the state of the real cell they are replacing. They're small though, so all the real computation work they may need to do is offloaded to a computer (over radio signals perhaps, or whatever.) Perhaps we can even optimize their operation such that communication with other robot cells that may happen to be next to it takes place inside the computers modelling both cells, instead of actually firing off the connection "for real".

Preform this operation once, and few would argue that the mind in question has died, been replicated, ceased to operate and been replaced with another... anything. It's just the same mind.

If you are willing to accept that (and if you're not, we'll just have to disagree), then preform the operation again. And again. And again.

This is what sodiumphosphate was referring to by "metamorphosis", and it does not require dualism.

http://en.wikipedia.org/wiki/China_brain

http://en.wikipedia.org/wiki/Ship_of_Theseus#Human_body

We all really want to accept this idea. It is inviting. Not accepting it has a lot of scary implications. If small changes in the matter that makes up my mind "kills" me, then what happens when my body naturally replaces parts. In neurons, the whole cell is rarely replaced, but all components of it all, none of the atoms are there forever, it is only a matter of scale to replace neurons with "working replicas". So, accept that somewhere along the way of "perfect replicas" I think you stop being the same person for any rational reason, then by scaling that reason down simply changing out atoms in the natural process of life kills "me" just as surely.

"No man ever steps in the same river twice"

Replacement with the subtly different is interpreted by our minds as "change". You no more "die" when the cells or atoms in your brain are replaced than a river dries up when all the water molecules you could see at one point in time flow away.

Exactly. "You no more "die" when the cells or atoms in your brain are replaced than a river dries up when all the water molecules you could see at one point in time flow away." when we find a way to measure this little death relative to the bigger more permanent one we can make interesting arguments. My advice, assume the transporter/uploading-machine will kill you. You will use it anyway for the same reason you use a credit card at the grocery store or corner market, you will be worried that the people behind you will be annoyed by the delay caused from your hesitation and the person who comes out the other side will not begrudge you for creating them.

If you want to define change to be a type of death, go ahead. As far as I can tell your position is philosophically sound though I disagree that it is makes for interesting discussion.

The difference is that the original you exists on a consistent space-time arc. Copy of you diverges from that, and becomes not you. To external observers, not you appears to be exactly like you but it isn't you because your mind is a process that is tied to that arc. Not you starts as you but then operates within alternate time-space arc.

In the case of metamorphosis there is only one "you" at any point in time. The concept of divergence doesn't make any sense if there is only one you. Diverge from what?

It would need to be really exactly the same, otherwise it is actually just a damaged neuron and the rest of the brain will continue normally, working around it just as it would a normally dying cell. Until some tipping point was reached, and what would you be - perhaps a read-only version of yourself?

Eh, I think of it more as a thought experiment than an engineering proposal.

It hinges not on engineering (the mechanism for inserting an artificial cell and it communicating with an external computer) but whether consciousness is computable in a Turing machine. The new "you" might be deterministic.

I am very confident that humans do not represent nor contain a model of computation greater than Turing Machines.

Can a human solve the Halting Problem (without necessarily being able to express that solution as a program)? Does even recognizing the Halting Problem take us out of what is computable?

No, I see no evidence whatsoever for a human being able to solve the halting problem.

"recognizing" it is irrelevant and poorly defined.

Could you describe an algorithm that a human would fail to decide wether it will halt or not?

Show that a human can decide if an arbitrary program terminates. You are the one making an extraordinary claim (and make no mistake about it, the suggestion that humans can be used as oracle machines is an extraordinary claim.)

Simply assuming it is the case because you want it to be the case is not science, it is religion.

I'm just a bit skeptical since I have never encountered a program so far which I couldn't decide whether it would halt or not. You would completely convince me if you could describe such a program. Also, this is not an extraordinary claim. According to Wikipedia, it is an open question:

> It is an open question whether there can be actual deterministic physical processes that, in the long run, elude simulation by a Turing machine, and in particular whether any such hypothetical process could usefully be harnessed in the form of a calculating machine (a hypercomputer) that could solve the halting problem for a Turing machine amongst other things. It is also an open question whether any such unknown physical processes are involved in the working of the human brain, and whether humans can solve the halting problem.

http://en.wikipedia.org/wiki/Halting_problem

When you do that you are doing nothing more than applying heuristics, preforming limited simulation, looking for repeated states. All of these things are things that may be preformed by algorithmic computation. That we don't have IDEs already doing all of this for us is a reflection of nothing more than the current state of machine learning and the relative computational densities of today's electronic computers and the human brain.

Being able to solve the halting problem for programs generally seen in real life programming does not imply in the slightest that you can solve the halting problem for arbitrary programs. Can you look at arbitrary Turing machine tapes (large enough to eliminate the possibility that you are simulating it without realizing it of course) and non-algorithmically decide if they will terminate? Can you in fact do anything non-algorithmically? That is in essence what you are suggesting, the non-algorithmic nature of the human mind.

You are of course not the first to suggest a non-algorithmic mind. The likes of Roger Penrose have also suggested similar things (see his The Emperor's New Mind and later Shadows of the Mind). His reputation is enough to give me serious pause, and the fact that he does not seem to be a dualist further inclines me to listen to what he has to say.

If you want to delve further into this subject I suggest you check out Penrose's work, then read the criticism of it from his peers. Penrose has mounted the most qualified defence of the non-algorithmic mind of which I am aware, but even so acceptance of his thesis is rather rare in academia. It is not light subject matter but the general consensus among experts in the fields which he touches is that in order to support his thesis he made numerous errors. In absence of their expertise, I must defer to their assessment of Penrose's work.

I have never encountered a program so far which I couldn't decide whether it would halt or not. You would completely convince me if you could describe such a program

Does this halt? Assume all variables are arbitrary precision integers.

/* http://en.wikipedia.org/wiki/Perfect_number#Odd_perfect_numb... */

  void searchForOddPerfectNumber() {
    int n = 1, sumOfFactors, factor;

    while (1) {
      sumOfFactors = 0;
      for (factor = 1; factor < n; factor++)
        if (n % factor == 0)
          sumOfFactors += factor;
      if (sumOfFactors == n) break;
      n += 2;
      sumOfFactors = 0;
    }
  }

uh. I wasn't disagreeing with you...?

"Consciousness is mortally bound to the physical body, and will die along with it"

I take it you would find it very hard to meet your copy, then? If for some reason your copy goes live and you don't die, I bet you two would get into a fight :-).

As it is now, if I'm alive and I meet my exact copy, he'd agree to die ("just do it quickly") until I really die.

And then the copy would become me - it's that simple. Maybe later it'd be possible to download myself into a body again, in which case I would retain all the knowledge that I acquired inside the virtual world.

Um, that would be murder. Furthermore, it wouldn't even be necessary: just go your separate ways, and when you die and "become" your (second) copy--this time, you time it correctly--you will still live on, even though you have a clone out there.

This was my favorite subject for a while and I arrived to a similar idea of transformation, except without nanobots: the computer becomes a continuation of your brain and then your biological brain is gradually killed cell-by-cell.

However, the idea that you still get to die after backup is based on an assumptions that I don't find neither obvious nor true: that the stream of consciousness is fully continuous and never stops. I've recently seen a documentary about a guy who was declared brain dead and yet recovered into being himself again. So it might still be possible to "upload" a dead brain in which case your experience is that of a resurrection which doesn't sound so bad.

I'm wholly relieved that someone else thinks this way too ( still aware of the fact that most thoughts aren't unique). I never came to the conclusion of metamorphosis, however.

Just felt a need to express my experience of camaraderie on the subject.

Your body is transforming at this very moment through mitosis. Gradually, cell by cell and depending on what kind of activity you are performing you are becoming stronger, smarter, weaker or dumber. Regarding consciousness, my personal belief is that there is no continuity and it's more like the frame rate of a video or sample rate of a song.

You could read about the Buddhist concept of impermanence and the five aggregates of being which sounds similar to the idea of a metamorphosis, only not just human but everything changing all the time.

In your metamorphosis example, is the finished project essentially be a robot? Would you have the same problem when a software agent is transferred from one computer to another?

Assume a negative answer. Then, the interesting implicit belief, is that there is something special about body composition. Whereas in physical law, there is nothing unique in principle about the body. So, the laws would have to be wrong or incomplete(fail to include consciousness) in an important way.

An interesting thought, there is a difference between gradually replacing your cells with mechanical/electrical equivalents, and copying your consciousness to a machine.

How? Well, think of replacing a hard drive under a running process. Compare that to migrating a VM to another machine. In one, the process is truly continuous, it just begins using new hardware; in the other, the process is cloned and the original process killed.

if you are aware of anything dealing with this concept of human metamorphosis, fiction or otherwise, I would appreciate a link.

This free Cory Doctorow piece could float your boat: "0wnz0red - Programmers who hack their own bodies don't need exercise and never get sick" http://www.salon.com/2002/08/28/0wnz0red/singleton/

Greg Egan has quite a few amazing stories dealing with the transition process. "Transition Dreams" is the one I remember, it is a bit dark.

I cant find a free link, but here is a paid e-book, $0.59: http://www.fictionwise.com/ebooks/b876/Transition-Dreams/Gre...

Probably a dumb question; have you tried reading glasses?

It's hard to die but it must be easier when you know that you are not gone.

Watch "The Prestige".

I disagree. Your individual consciousness will diverge of course (you are just a meat machine) but your computer copy will continue on and your ideas, ideals, and personality would continue.

Writing this I just had a major existential crisis because I realized that at the exact point of divergence there is a point where 'you' are both alive and dead at the same time, Schrodinger's Tomb.

I agree with you in that I think a gradual change is less crisis inducing even though it equals out to the same thing. I think that I'd get a brain backup anyway, just in case.

Reply on news.ycombinator.com