Brain Transplant

[TomAtBeseck]

Done.

This is all very interesting. The real answer is: "We don't know!" And I suppose we won't be sure of these answers until someone truly identifies what physically constitutes conciousness and then physically reproduces it.

[Onar Åm]

This is a topic I am very interested in. I used to work at Webmind, an AI company, a few years ago, and back then I took it for granted that consciousness could be created in a computer by simply replicating the functional patterns of the brain. Now I am not so sure. I've come to look at consciousness as a kind of "ether" which can be shaped and resonated by matter. In this view our brain is actually literally an organ -- a kind of "musical" instrument -- which creates standing waves which we experience as consciousness. Now, just like the organ is not the same as the sound produced by the organ, I think it makes sense to view the brain as the thing that *produces* consciousness, but is not the same as it.

From this perspective it is not at all self-evident that consciousness can be created in a silicon chip simply by replicating the functional structures, just like you cannot create sound by creating a perfect 3D model of a church organ in a computer. It's not even self-evident to me that we would retain our consciousness if we simply replaced all the cells or atoms in our brain with new ones. In fact, there is some biological hints of evidence against this: neurons don't typically replicate. Unlike the rest of our body we have the same nerve cells our whole life. That may not be a coincidence. It could actually have been selected for as a precondition for retaining consciousness through time.

Now, why would I hold that consciousness is something different from matter? In short, free will. In order for consciousness to be an agent of causation it actually has to BE something, and something etherlike works for me. The advantage of this model is that consciousness and matter are then closely intertwined. Consciousness cannot exist without the brain, just like the harmonic sound cannot exist without the organ.

[VikingF]

I find this topic very interesting too. If my "self" is something natural that is produced by my brain, then I wonder about two questions, namely:

1. Could this brain have produced another self than me?

and

2. Could another brain have produced the same self that happens to be me?

If the answer to the first question is "yes", then to copy the brain pattern to another location may lead to a self that is just identical to me, but who is not me, and if the answer to the second question is "yes", then I could reappear in any brain regardless of whether it is completely different from the one that produced me 25 years ago or not.

Edited March 3, 2007 by VikingF

[DavidOdden]

No way you guys are a coincidence. You must have a club. BTW I'm so sorry for you that your weather sucks.

1. Could this brain have produced another self than me?

Snip the alternative restatement, since I think these are the same question, really. The central question here is what a "self" is -- it's not your feet, or liver, or blood, or snout. It's your consciousness. So then you have to inquire about the relationship between a consciousness and a brain. Is it the case that all aspects of a consciousness are contained in the brain, or are there other aspects of consciousness that are not in the brain? There are aspects of the body that are not in the brain which are relevant to consciousness (eyes, ears, toes, nose), but they don't house the consciousness.

The problem that I have with the BIV scenario (and variants, like brain transplants), is that they ignore the fact that consciousness is entirely dependent on non-brain stuff. So let me explain in a lightly-detailed, personal way why "identity" would be non-identical under brain transplant. My nature, from a cognitive perspective, is founded on what I perceive, since that's man's only basis of knowing anything. My particular eyes preclude me distinguishing certain color differences, and at this point in life, I'm also grappling with acoustic problems that especially affect speech perception. There are other facts that I can concretely relate to electrical conductivity of my skin, and my height. The brain-transplant identity scenario assumes that no fact of one's perceptual apparatus has relevance to your consciousness, but I dispute that. In fact, a horking large part of my nature and professional life is tied up in my perceptual abilities, especially my ears. It's conceivable that the essential difference is all in the cortex and not the basilar membranes, but that's an unanswered scientific question, and not a philosophical one.

Or, to put it another way, if you really think that it doesn't matter, and if there is some method of "brain transplanting", go ahead and step out in front of an on-rushing car, and see if there is a difference.

[Leonid]

The main queistion is :What this inorganic immortal brain needs consciousness for? The consciousness is not an end in itself, this is our only tool of survival. If one's existance is secured, one doesn't need consciousness. Ayn Rand tought about this problem already 46 years ago. That what she said" Try to imagine an immortal, indestructable robot, an entity which moves and acts, but which cannot be affected by anything, which cannot be changed in any respect, which cannot be damaged, injured or destroyed.Such an entity would not be able to have any values; it would have nothing to gain or to lose...it could have no interest and no goals" ( The objectivist ethics in The Virtue of selfishness pg 16 1961). Such artificial brain doesn't need and will not have any consciousness. The only thing it can do is to entertain itself with previous memories from the times when it was human.

Leonid

Edited March 3, 2007 by Leonid

[SteveCook]

Hello there. I have read the number of posts that have been placed on this topic and note that many of the posts refer to consciousness as if it is an actual "somthing". Indeed, in one post, I if I understand the meaning of it correctly, there was a suggestion that replacing aneuron with something else would rob thge brain of the consciousness that was presumably a fundamental property of that neuron. I should like to put forward ther following hypothesis.

Whatt if consciousness doesn't actually exist as a phenomena in and of itself. What if consciousness is merely an emergent property of the simutaneous action of all parts of the brain. I suppose an analogy might be one of flight. Imagine taking a plane apart and laying all of the individual parts out on a runway, right down to the last nut and bolt. Each one of these parts would be unlikely to exhibit the properties of flight. No, the only way you would be able to understand the emergent property of flight is to put all of the parts together and throw it off a very big hill.

In the same way, I think "consciousness" does not really exist as a physical property of any part of the brain. Rather it "emerges" as a phenomenon wwhen all of the brain is working as a coherent whole.

The part of you that thinks of themself as "You" is, I suspect, an expression of the emergent consciousness I have mentioned above. Thus, if we were to replace each of the parts of the brain in turn, I see no reason why that sense of "self" should be affected. All of the above would, of course, require a fantastic technology so as not to affect the proper whole-brain operation which would in turn impinge upon the emergent consciousness. But, for the purpose of this thought experiment, we can assume that the technology exists.

[SteveCook]

Regarding my last post on this topic...

I have just finished reading abook by JAmes Lovelock called "Revenge of Ghia". This particular book was concerned with climate change on Earth. However, it is based on a thoery of how the Earth self regulates its climate so as to render the climate ever more fit for life.

The general thrust of the Ghia Theory states that all of the organic processess on the earth, when operating simulataneously, behave as if they have a particular goal, that of climate stabalisation. The author goes to great lengths to make sure the reader understands that he doesn't actually believe that the Earth has any conscious intention. Merely that it acts as if it is conscious.

Something occurs to me.....

Lovelock appears to be suggesting that the apparent goal directed behavious of the earth's various biological systems ais merely an emergent property of all of those systems acting in concert. Surely this is no different to my previous post that suggested that human consciousness is the emergent property of a fully functioning brain. i guess what I am trying to say is that if, for arguments sake, we accept my hypothesis that human consciousness is both real and an emergent property of brain functioning, we mjust also, in principle accept that Ghia (the whole planetary biosphere) is also conscious by virtue of a structurally identical process. Alternatively, we should regard consciousness as being an illusion in both.

[DavidOdden]

Whatt if consciousness doesn't actually exist as a phenomena in and of itself.

What does that even mean? Consider the contrasting question "What if death doesn't actually exist as a phenomenon in and of itself?". Or, to shift attention from phenomena, "What if lions don't actually exist as existents in and of themselves?". I think it's easy to see that this is a facile question that a thinking man should never set forth. What, then, is your real question? You're invoking a spurious distinction between "existence" and "emergence". The latter is a vile intellectual scam, and I urge you to run, not walk, away from the crap-pile that is emergence-technology.

[Onar Åm]

You're invoking a spurious distinction between "existence" and "emergence". The latter is a vile intellectual scam, and I urge you to run, not walk, away from the crap-pile that is emergence-technology.

David, could you elaborate why emergence is "a crap-pile"?

[SteveCook]

What does that even mean? Consider the contrasting question "What if death doesn't actually exist as a phenomenon in and of itself?". Or, to shift attention from phenomena, "What if lions don't actually exist as existents in and of themselves?". I think it's easy to see that this is a facile question that a thinking man should never set forth. What, then, is your real question? You're invoking a spurious distinction between "existence" and "emergence". The latter is a vile intellectual scam, and I urge you to run, not walk, away from the crap-pile that is emergence-technology.

Ok. Fair enough. My initial thoughts on this subject have been vaugely set out and I must account for that. Let me try again and see if I can make a better job of it.....

Perhaps I should avoid the word "emergent" since it rouses such a vitriolic response in you. Let me phrase the meaning of my earlier post in another way. What I am trying to suggest is that consciousness is a "consequence" or "effect" arising from the distributed action of all parts of the brain operating at once and in concert. Consciousness, in this sense, has no meaning unless it occurs in the whole brain functioning context I have just mentioned. It is in this sense, that I call it "emergent" because its "existence" "emerges" out of that whole-brain functioning. Thus, ff we were to take any individual part of the brain and inspect it for evidence of consciousness, we would arguably find nothing there; because there is nothing there. At least at the level of the constituent part. to use the old psychologcal term "Geshtalt". The whole is greater than the sum of its parts.

[DavidOdden]

David, could you elaborate why emergence is "a crap-pile"?

Because it straddles the boundaries of the mystical and the self-evident. My main objection is that it's used as an answer when it isn't one. Let's take the properties of iron, which is made up of electrons, protons and neutrons. If you understand electrons, protons and neutrons individually, you still don't understand iron. So iron is an "emergent phenomenon". Now I don't think anybody has ever really claimed that all you need to know, to understand iron, is the properties of the component particles, so invoking emergence would be self-evident -- obviously, we have to know more about iron than what the parts are. We can add in electro-magnetism, the weak and strong nuclear forces, and I dunno maybe we really can at present explain everything about iron based on those 6 things.

Maybe the simplest explanation of what's wrong with emergence is that it may mislead people into thinking that a problem has been solved. Rather than trying to actually understand the nature of consciousness, saying that it is "emergent" obscures recognition of the fact that we don't understand it, and wrongly gives the illusion of having at some level resolved the matter. It is also gravely mistaken to think that the idea of parts interacting is a novel insight. Indeed, Neptune was discovered because of such part-interaction calculations.

[Onar Åm]

It is in this sense, that I call it "emergent" because its "existence" "emerges" out of that whole-brain functioning. Thus, ff we were to take any individual part of the brain and inspect it for evidence of consciousness, we would arguably find nothing there; because there is nothing there. At least at the level of the constituent part. to use the old psychologcal term "Geshtalt". The whole is greater than the sum of its parts.

I have to agree with David here that you are obscuring things. The question is not whether the brain acts in such a way as to "bring forth" consciousness -- this is obvious -- but rather whether consciousness is something *other* than the brain. I think there is solid arguments that indeed consciousness is not the same as the brain, just like the sound is not the same as the flute.

I like the old mythological image of a group of worshippers that "evoke" a spirit, which then takes control over its worshippers and command them what to do. Without the evokation of the worshippers the spirit could not exist as a unity, yet the spirit, once evoked, exerts a controlling influence on the worshippers. I think that the brain in a similar manner evokes consciousness which then becomes an agent of causation. Clearly consciousness is "emergent" in this view, but NOT the same as the brain.

[DavidOdden]

It is in this sense, that I call it "emergent" because its "existence" "emerges" out of that whole-brain functioning.

I think the problem comes from your understanding of "existence". Consciousness exists, but it's not a thing, as an electron or a cow is a thing (although a cow could be deemed an emergent phenomenon, but I'll refrain from doing so). And I should point out that the entity / existent distinction is often muddled, which can lead to the wrong-headed view that relations don't exist. A few quotes from ITOE may help (from ch. 1): "The building-block of man's knowledge is the concept of an 'existent'—of something that exists, be it a thing, an attribute or an action."; "The (implicit) concept 'existent' undergoes three stages of development in man's mind. The first stage is a child's awareness of objects, of things—which represents the (implicit) concept 'entity.' The second and closely allied stage is the awareness of specific, particular things which he can recognize and distinguish from the rest of his perceptual field—which represents the (implicit) concept 'identity'."

The fact that you can't put pure consciousness in your hand and hold it doesn't mean that it doesn't exist, that it isn't an existent. I think you could correctly conclude that consciousness isn't an entity. Similarly, "falling" isn't an entity, nor is "sorrow", but they both exist.

[SteveCook]

I have to agree with David here that you are obscuring things. The question is not whether the brain acts in such a way as to "bring forth" consciousness -- this is obvious -- but rather whether consciousness is something *other* than the brain. I think there is solid arguments that indeed consciousness is not the same as the brain, just like the sound is not the same as the flute.

I like the old mythological image of a group of worshippers that "evoke" a spirit, which then takes control over its worshippers and command them what to do. Without the evokation of the worshippers the spirit could not exist as a unity, yet the spirit, once evoked, exerts a controlling influence on the worshippers. I think that the brain in a similar manner evokes consciousness which then becomes an agent of causation. Clearly consciousness is "emergent" in this view, but NOT the same as the brain.

Ah...well...I must agree with you that I have provided an incoherent account of my argument. Because, in fact, I pretty much agree with the definition of conscious that you set out above. That is to say, it is an emergent property of distributed brain function. However, having "emerged" from this process, consciousness may well have a self-directing life of its own despite the fact thats it's very existence rest upon the brain functioning that is operating "below" it.

Which leads me back to my earlier post. Namely that of the Ghia Theory of a self regulating biosphere. If, for arguments sake, we accept the definition as outlined above of what consciousness is, then the various systems of the bioshpere of the earth, when acting at once and in concert, might be seen as evoking consciousness. Indeed, the biosphere does seem to behave in such a way as to imply conscious goal directedness. Now, the scientific proponents of this theory are always at great pains to qualify their theory with the statement that the biosphere merely acts as if it is consciously goal directed. It just seems to me that if we would baulk at the thought that consciousness could emerge from the distributed simultaneous action of various biological systems of the Earth's biosphere, then we should similarly baulk at the idea that consciousness emerges from the distributed action of all of the neuronal systems of our brain.

My own feelings on this are ambivalent. I just feel that it is inconsistent to baulk at the idea in one sphere whilst holding to be tenable in another. Though, I intuitively feel my own consciousness to be real as I experience it. So I guess I must consider the possibility that the whole earth biosphere is also conscious or "sentient" in some "emergent" sense.

Edited March 4, 2007 by SteveCook

[DavidOdden]

Though, I intuitively feel my own consciousness to be real as I experience it. So I guess I must consider the possibility that the whole earth biosphere is also conscious or "sentient" in some "emergent" sense.

No, you should not consider that possibility. If you had some actual evidence to support the idea that the so-called "biosphere" is conscious, then you could consider this idea. But there is no such evidence. If you are going to "have to" consider every random idea that comes down the pike, then you should give equal time to the idea that the sky is made of green cheese; is filled with invisible pigs; is a solid unless something tries to move through it, and so on. Common sense will tell you that the earth is not a living organism. If may contain living organisms, but it isn't one, itself.

[Onar Åm]

Which leads me back to my earlier post. Namely that of the Ghia Theory of a self regulating biosphere. If, for arguments sake, we accept the definition as outlined above of what consciousness is, then the various systems of the bioshpere of the earth, when acting at once and in concert, might be seen as evoking consciousness. Indeed, the biosphere does seem to behave in such a way as to imply conscious goal directedness. Now, the scientific proponents of this theory are always at great pains to qualify their theory with the statement that the biosphere merely acts as if it is consciously goal directed. It just seems to me that if we would baulk at the thought that consciousness could emerge from the distributed simultaneous action of various biological systems of the Earth's biosphere, then we should similarly baulk at the idea that consciousness emerges from the distributed action of all of the neuronal systems of our brain.

My own feelings on this are ambivalent. I just feel that it is inconsistent to baulk at the idea in one sphere whilst holding to be tenable in another. Though, I intuitively feel my own consciousness to be real as I experience it. So I guess I must consider the possibility that the whole earth biosphere is also conscious or "sentient" in some "emergent" sense.

I was fascinated by Gaia-theory in my younger years, but as I have studied climate change and evolution it no longer seems like a very convincing idea. The very idea of a stable/stabilizing environment is a myth. The apparent stabilizing properties of an ecology is due to the adaptiveness of its components, namely the organisms. Thus, it is not correct to say that fire is used as a way to control and stabilize a forest ecology, but rather that the ecology of organisms that has evolved has adapted to frequent fires. I am therefore thoroughly skeptical of any claim of the ecology as a homeostatic entity that tries to maintain its unity. The ecology is more like a fire than an organism: it feeds blindly off the material that happens to be available.

As to the biosphere being conscious: there is absolutely no evidence that it is behaving consciously or goal directed. A fire could also said to be behaving "goal directed" by consuming everything in its path, but closer inspection shows this to be false.

Notice that we aren't even conscious with our whole bodies. We do a lot of things that are unconscious to us. In fact, consciousness seems to be limited to a particular kind of cells: nerve cells. Is this a coincidence? Maybe, but it suggests to me that consciousness is not merely "fickle" relations, but something much more solid. Notice how telepathy never has evolved in any organisms. If Gaia could be conscious, wouldn't telepathy be rather common in the biological world? In fact, consciousness seems to emerge ONLY in well-connected nervous systems. I.e. if a nerve is severed from the central nervous systems, all sensation from this nerve vanishes immediately. This suggests to me that contiguity is an essential requirement of consciousness. Distributed systems cannot be conscious.

Notice one possible exception to this: if nerve cells also were electromagnetic transmitters and receivers then organismic consciousness carried by radio waves is conceivable. In that case a kind of "distributed" consciousness could be possible. HOWEVER, that's not the kind of distributivity we are talking about in a biosphere. There,allegedly organisms that are completely physically isolated from each other (i.e. no physical interaction of any kind takes place) form a Gaian consciousness, and I just don't see it. It appears like a mystical idea to me.

[Leonid]

Ah...well...I must agree with you that I have provided an incoherent account of my argument. Because, in fact, I pretty much agree with the definition of conscious that you set out above. That is to say, it is an emergent property of distributed brain function. However, having "emerged" from this process, consciousness may well have a self-directing life of its own despite the fact thats it's very existence rest upon the brain functioning that is operating "below" it.

Which leads me back to my earlier post. Namely that of the Ghia Theory of a self regulating biosphere. If, for arguments sake, we accept the definition as outlined above of what consciousness is, then the various systems of the bioshpere of the earth, when acting at once and in concert, might be seen as evoking consciousness. Indeed, the biosphere does seem to behave in such a way as to imply conscious goal directedness. Now, the scientific proponents of this theory are always at great pains to qualify their theory with the statement that the biosphere merely acts as if it is consciously goal directed. It just seems to me that if we would baulk at the thought that consciousness could emerge from the distributed simultaneous action of various biological systems of the Earth's biosphere, then we should similarly baulk at the idea that consciousness emerges from the distributed action of all of the neuronal systems of our brain.

My own feelings on this are ambivalent. I just feel that it is inconsistent to baulk at the idea in one sphere whilst holding to be tenable in another. Though, I intuitively feel my own consciousness to be real as I experience it. So I guess I must consider the possibility that the whole earth biosphere is also conscious or "sentient" in some "emergent" sense.

The crude analogy of relation between mind and brain would be the relation of software and computer. A computer has the ability to process information, and software “knows” how to do that. Software is based on some physical substance like a floppy disc or CD-ROM, but its essence is information on how to process data. The brain is a tool which processes sensory-perceptual data and the mind knows how to do that. The difference is that brain can generate its own software .

[Eduffy]

This is not a hypothetical.

Your cells are constantly being replaced. Most within just a few days, some last several years, but physically none of who you are today existed 10 years ago.

This leads me to believe that the self is not a physical entity, although memory is. If there is a self outside the physical and it existed before and/or will exist after this life, I don't know that you'd have any memory of any previous existance as you will have left the vehicle that contained the memory storage.

To make it a bit trippier, you could travel from one body to the next and have no memory of the previous body. You also would have no reason to believe that you haven't been in the current body for its whole life since the only memories you can now access are those within that body. For all you know you could have arrived in your current body five minutes ago.

[Onar Åm]

This is not a hypothetical.

Your cells are constantly being replaced. Most within just a few days, some last several years, but physically none of who you are today existed 10 years ago.

This leads me to believe that the self is not a physical entity, although memory is. If there is a self outside the physical and it existed before and/or will exist after this life, I don't know that you'd have any memory of any previous existance as you will have left the vehicle that contained the memory storage.

To make it a bit trippier, you could travel from one body to the next and have no memory of the previous body. You also would have no reason to believe that you haven't been in the current body for its whole life since the only memories you can now access are those within that body. For all you know you could have arrived in your current body five minutes ago.

I agree that this is a possibility. It could very well be that if you configure atoms in a particular way, they will generate YOU in a particular state. But not all cells are constantly being replaced. Nerve cells (with a few exceptions) are not replaced. You typically have the same nerve cells throughout your entire life. Whether you also have many of the same atoms in the brain would be interesting to know, but I suspect that at least some parts of nerve cells are replaced with new atoms. In any case, what is the biological reason for not regenerating nerve cells? One intriguing possibility is that we really can't replace our cells (or our atoms) without changing who we are.

[SteveCook]

This is not a hypothetical.

Your cells are constantly being replaced. Most within just a few days, some last several years, but physically none of who you are today existed 10 years ago.

This leads me to believe that the self is not a physical entity, although memory is. If there is a self outside the physical and it existed before and/or will exist after this life, I don't know that you'd have any memory of any previous existance as you will have left the vehicle that contained the memory storage.

To make it a bit trippier, you could travel from one body to the next and have no memory of the previous body. You also would have no reason to believe that you haven't been in the current body for its whole life since the only memories you can now access are those within that body. For all you know you could have arrived in your current body five minutes ago.

Actually, the brain and most (though not all) of the attendant central nervous system is the one part of us where cells are not replaced as a matter of course. There is some evidence that if a part of the brain is damaged, then some regeneration of cells takes place, but this is rather limited and happens more vigorously the younger the individual is. All of which makes obvious sense, given that the brain is where we store memories. It would not be very clever if all of the cells of the brain were fully replaced every few years.l It would effectively mean that any memories we possessed would only extend back as far as the oldest neuron. So, it is simply factually incorrec to say that all of a person is a person is literally no more than 10 years old at any point in their life.

Edited March 5, 2007 by SteveCook

[SteveCook]

As to the biosphere being conscious: there is absolutely no evidence that it is behaving consciously or goal directed.

As for the biosphere being "conscious". Yeah maybe I'm overcooking the egg there. Ok...I AM overcooking the egg....Alright....I'm probably talking bollocks.....Oh go on then...I'll admit it....I AM talking bollocks....

However, I would still tentatively suggest that the biosphere might still be considered as being seen as behaving as if it is a unitary organism that has (albeit unconscious) goal directed behaviour. Self awareness? No. But in much the same way as the human phenotype is actually an expression of the differing "goals" of individual genes that make up the human genotype (I have put quotation marks around the word "goals" because, of course, genes don't have goals. They merely act as if they do), if any of those genes act in such a way as to endanger the rest of the genotype, the rest of the genotype has whole-genotype defense mechanisms that act in concert with one another to inhibit such behaviour. It's not that all of the othere genes "know" that they are acting as in concert with their genotypic neighbours. It's just that any gene that randomly evolved the tendancy to do so would fare better that genes that did not. Eventually, given enough evolutionary time, we end up with genotypes that look and act as if they are a unitary goal-directed entity. In the same way, i guess I am trying to suggest that, at least at some structurally similar level the whole earth bioshphere is doing the same. Anyway, I am going to leave this giia thing alone now cos I know it has caused me to drift completely off track with regards to this topic's theme...apologies for the indiscretion

Edited March 5, 2007 by SteveCook

[-archimedes-]

Here's an interesting thought experiment that I've been contemplating. I read somewhere that researchers were able to, or soon would be able to, create an artificial hypothalamus of a human brain. Let's take this further, and suppose that one by one, a section of your brain was replaced with a artificial, yet fully functioning component complete with identical memories contained in the section of the brain being replaced.

Presumably after each operation where one section is replaced, you would still act, percieve, and think the same because the replacement parts exactly duplicated the function of the brain section being replaced.

Is there a point where you are no longer you?

First off, I'll submit that I am more so in favor of the concept of brain replacement (i.e., replacing one's own brain with that of a petri-dished/test-tubed brain cultured from healthy cells and what have you, and grown to an appreciable age/state of development and inter-lobal structural complexity capable of retaining the amount of information in the subject individual's mind [which wouldn't take all that long at all]) with that of a lab-cultured brain..., technology which we have readily at hand..., as opposed to that of the use of an "artificial" apparatus, given their apparently/proven inherent problems and difficulties with integration with the human physiology, e.g., the artificial heart.

With that said, I would have to say that the "point where you (were) no longer you..." would come into play at the point wherein it was time to replace the component of an individual's mind that consisted of their sense of self/the aspect of the human mind that was/were made up of what amounts to the pre-perceived, Freudian, three-part psyche, i.e., the id, ego, and superego.

In other words, you would stop being you the moment this aspect of your mind were removed and would remain as such up until the point of time that this aspect were re-synchronized with the other "artificial" components, likely through the process of neural imprinting.

[Gryfonwyng Neuroartisan]

Here's an interesting thought experiment that I've been contemplating. I read somewhere that researchers were able to, or soon would be able to, create an artificial hypothalamus of a human brain. Let's take this further, and suppose that one by one, a section of your brain was replaced with a artificial, yet fully functioning component complete with identical memories contained in the section of the brain being replaced.

Presumably after each operation where one section is replaced, you would still act, percieve, and think the same because the replacement parts exactly duplicated the function of the brain section being replaced.

Is there a point where you are no longer you?

Every atom in our central nervous system is changed out at least on a yearly basis. Why should what you suggest make the slightest bit of difference? It's the same thing, boss. If these implants are performing exactly or almost the same functions, then it would be no different for them to replace you than for you to continue to live for another year. In that timespan, you'll have ceased to exist. There will be another person in your place that is roughly based on the template of your present self, and here's the sick thing: it will sincerely think that it is you in every single way. It will know your darkest secrets and your most deeply hidden fears. There are parts of your personality that it will have as much contempt for as you have for who and what you were last year, and you won't even be there to defend yourself. Your shame will be there in plain sight of another individual, and he will judge you without pity. Be afraid, sir. Be very afraid.

[ilrein]

Theseus takes a ship loaded with lumber cargo to a destination. On the first day on route, he replaced a plank with some of the cargo. The next day he replaced another one. By the time he reached his destination, the original material of the ship had completely replaced.

The question is asked: "is the ship the same as when he left?"...

You see, this is only a paradox because of the way the question is asked, relying on context-dropping to purposefully confuse the student. It blurs the line between metaphysics and epistemology by assuming the concept of the ship is the same as the materials that compose it. The entire strength of the question is simply a question of context, what exactly does the asker of the question mean when he uses the word same? After that, the answer is self-evident.

http://forum.ObjectivismOnline.com/index.p...t=0&start=0

[ZSorenson]

Thanks Ifat, that was helpful. This issue has bothered me since High school. What innitiated it was 'star trek'. When they beam or teleport, as I understand it, they take a dna picture of them, and recreate them from that map on the other side. Seems to me, that the 'me' on the other side as well as everyone he was familiar with would be fine with it, but I doubted that the original me would still exist which makes me a little uncomfortable. That is where I ran into a similiar problem. What if you were to replace a single atom of your brain? Would you still be you? We gain and loose cells everyday so it would seem unlikely that to replace a carbon atom, or even molecule should cause any change. what about a billion, or 50 billion?

It seems to me that on this level, you would be fine so long as you didn't change locations and did it gradually so as to not upset the electrochemical balnce that we experience as conciousness. So Everything would need to be replaced piece by piece and allowed whatever time was necessary to be integrated within the confines of the system.

Though there's a book, the "physics of star trek", there is also the "metaphysics of star trek", which explains that teleporters are designed to leave a distinct minute lag time between the disintegration of your cells and their reintegration - at which point the metaphysical 'soul' automatically and instantaneously migrates. Without this lag time, the resultant reintegration is a vegetable mind. Again, there is a tremendous tendency of physicists in particular, but scientists in general, to accept absurd mystical beliefs despite being atheist. I almost wonder if there's a secret club....