The Ship of Theseus and the Ephemerality of the Self

[Ancient Aliens]

Recently I have been applying the Ship of Theseus paradox to the human brain, and further, to the question of human immortality.

Theoretically, if we were to replace a persons (let's call this person Bob for the sake of simplicity) brain, neuron by neuron, with cloned tissue, at what point (if any) would he fail to be Bob and simply be Bob 2.0? Would it matter if Bob was conscious during this process or not? And ultimately, does this question even matter as we will never know the true answer (as the theoretical Bob 2.0 would have the same memories as Bob and would be indistiguishable)?

Going further, I wondered theoretically if the original neurons from the original Bob were used to reform the original Bobs brain, would Bob 2.0 or Bob 3.0 be the true Bob? Or would neither of them be Bob because Bob is simply the electrical current or the chemicals which originally resided in Bobs brain and anything other than these would fail to be him?

Thinking along these lines, if anything less than the cancellation of the aging process all together were to be applied to a human being in attempt to gain immortality, would immortality be impossible due to the possibility of the ending of the original consciousness? Also along these lines; if the brain was to shut down and the electric current in the brain were to cease, would the original consciousness die, even if the brain was restarted?

What are you answers, questions, thoughts, concerns, and/or disagreements?

[Armatus]

If you recreate Bob you recreate Bob, it's Bob, but not the same Bob because like a new hard drive he would steer through a separate life in a different direction. Yet we do this every waking second, we steer ourselves in new directions creating new thoughts and memories. Bob is essentially Bob, but if the original Bob exists Bob 2.0 can't really say he's "Bob".

Edit: can't really say he's Bob in the sense that he wasn't Born, and Bob still 1.0 is still around.

[Ancient Aliens]

If you recreate Bob you recreate Bob, it's Bob, but not the same Bob because like a new hard drive he would steer through a separate life in a different direction. Yet we do this every waking second, we steer ourselves in new directions creating new thoughts and memories. Bob is essentially Bob, but if the original Bob exists Bob 2.0 can't really say he's "Bob".

Edit: can't really say he's Bob in the sense that he wasn't Born, and Bob still 1.0 is still around.

But what if you were to replace every neuron in Bob's head with a cloned neuron while Bob maintained consciousness? I personally suppose it would come down to whether the identity is electrical, chemical, or cellular in nature.

[Armatus]

But what if you were to replace every neuron in Bob's head with a cloned neuron while Bob maintained consciousness? I personally suppose it would come down to whether the identity is electrical, chemical, or cellular in nature.

Without reading all the responses

The distinction comes when you have two separate individuals with their own minds and feelings unknown to the other, co-existing. If you are cloned you (yourself) cannot experience nor control the clone and so it is not you. So no mater how similar you make the clone as long as it acquires separate consciousnesses the question is clearly no. That is not to deny 'It' is You in all regards to superficial considerations.

I can only imagine what people will say about ESP once we start creating clones of humans (not that cloning is necessarily the natural step in moving forward either).

[Taiji]

Bob2 will never be in the same location as Bob1, so they'll not be the same person in at least one way. But also, we would not be able to be able to observe them as being the same without generalising. We would be restricted to maps of the sameness/difference and so not know that they are existing in the same way in the inferred territory. So they might be the same in every respect except location but we would never know it.

In fact it seems that 'sameness' is created by generalisation, or an active removal of information in other words. There is no reason to believe anything has ever actually been the same in every respect as anything else. Or in other words X =/= Y, and X = Y has to be shown as simply Y.

[Ancient Aliens]

Bob2 will never be in the same location as Bob1, so they'll not be the same person in at least one way. But also, we would not be able to be able to observe them as being the same without generalising. We would be restricted to maps of the sameness/difference and so not know that they are existing in the same way in the inferred territory. So they might be the same in every respect except location but we would never know it.

In fact it seems that 'sameness' is created by generalisation, or an active removal of information in other words. There is no reason to believe anything has ever actually been the same in every respect as anything else. Or in other words X =/= Y, and X = Y has to be shown as simply Y.

I'm sorry for being hard to understand What I meant to say is that Bob1's brain is being replaced neuron by neuron, we aren't putting cloned neurons into the brain of a clone, we are replacing Bob1's brain cells with cloned cells. I am wondering at what point (if any) does the identity of Bob1 die and become a clone of Bob1 (Bob2). It's a question of human identity rather than questioning if a cloned individual the same as the original.

I'm applying the human brain to the Ship of Theseus paradox. For those that don't know the specifics:

A ship runs from Theseus to Crete. Over time the paint fades, and it is repainted. The timbers and the sail wear out, and those too are replaced. The crew ages, and eventually, it too is replaced. After quite some time, every single part of the ship had been replaced entirely. At what point (if any) did the ship of Theseus fail to be the original?

Hobbes added to this question by asking, "If the parts of the original ship of Theseus were preserved in a warehouse and they were used to reconstruct the original ship of Theseus, and the original crew were to be assembled, which ship (if either) would be the original ship of Theseus?

When applied to the concept of human identity it means at what point (if any), after replacing a brain piece by piece, would the original identity cease to be and a new one is created?

And if the original pieces of said brain were reassembled, which brain (if any), would have the original identity?

[Taiji]

It will not be possible to show that the cloned cells are the same. If you change anything then at no point will Bob be Bob anymore unless you generalise. So the whole question revolves around the extent to which you want to generalise. Bob2 is Bob1 no matter what is different if you generalise to a sufficient extent.

Maybe it helps to understand what I am saying if I point out that Bob at 18:15pm is not Bob at 18:16pm. Time, as well as location and other characteristics, must be included if you're identifying without generalisation.

And if the original pieces of said brain were reassembled, which brain (if any), would have the original identity?

Neither, both, and one, and the other. Without stating the desired level of generalisation your question will produce all 4 answers at once. Perhaps a level of generalisation is implied in 'identity', but it cannot be inferred from it. So the question is effectively meaningless since it generates a meaningless answer.

It's a shame when philosophers can't work out what a stupid question looks like, no offence intended.

[Ancient Aliens]

It will not be possible to show that the cloned cells are the same. If you change anything then at no point will Bob be Bob anymore unless you generalise. So the whole question revolves around the extent to which you want to generalise. Bob2 is Bob1 no matter what is different if you generalise to a sufficient extent.

Maybe it helps to understand what I am saying if I point out that Bob at 18:15pm is not Bob at 18:16pm. Time, as well as location and other characteristics, must be included if you're identifying without generalisation.



Neither, both, and one, and the other. Without stating the desired level of generalisation your question will produce all 4 answers at once. Perhaps a level of generalisation is implied in 'identity', but it cannot be inferred from it. So the question is effectively meaningless since it generates a meaningless answer.

It's a shame when philosophers can't work out what a stupid question looks like, no offence intended.

Why the intentional obtusion? It's a simple hypothetical question; answer it or don't.

[Taiji]

You think I am intentionally obtuse about a question I think is based on misconception? ...

Good luck with the alternative.

Maybe some more explaining would help. I'll do it with the ship too:

At what point (if any) did the ship of Theseus fail to be the original?

A split second after it was named, assuming it was named after being constructed. The origin of the 'Theseus' was it's completion and naming. That's my most exact answer at the moment.

Looking for an everyday practical answer?: When it sunk.

It's entirely dependant on whatever rules you choose to apply. For example, if you decide that it's location is a part of it's identity then it ceases to be your 'Theseus' the moment it moves. Which can be instantly or never depending on where you choose to measure movement from. Or for another example, you can decide the age of the crew is a part of it's identity. So 'Theseus' appears to last for no time at all, or up to a year by normal standards, depending how specific you want 'age' to be.

Like I said; you have to define the 'identity' of 'original Theseus'. The question is meaningless without it.

And there probably isn't a 'correct' answer to the question of how to identify Theseus. We'd all just be applying our rules for defining it's identity in different ways that are all based on data with loads of lost chunks. Noone would be right, and everyone probably has something useful about their approach.

[Ancient Aliens]

You think I am intentionally obtuse about a question I think is based on misconception? ...

Good luck with the alternative.

Maybe some more explaining would help. I'll do it with the ship too:


A split second after it was named, assuming it was named after being constructed. The origin of the 'Theseus' was it's completion and naming. That's my most exact answer at the moment.

Looking for an everyday practical answer?: When it sunk.

It's entirely dependant on whatever rules you choose to apply. For example, if you decide that it's location is a part of it's identity then it ceases to be your 'Theseus' the moment it moves. Which can be instantly or never depending on where you choose to measure movement from. Or for another example, you can decide the age of the crew is a part of it's identity. So 'Theseus' appears to last for no time at all, or up to a year by normal standards, depending how specific you want 'age' to be.

Like I said; you have to define the 'identity' of 'original Theseus'. The question is meaningless without it.

And there probably isn't a 'correct' answer to the question of how to identify Theseus. We'd all just be applying our rules for defining it's identity in different ways that are all based on data with loads of lost chunks. Noone would be right, and everyone probably has something useful about their approach.

There is no misconception, as that is the point of the discussion. I am wanting to hear other peoples opinion (in your words, their rules and answers). I'm not trying to define the answer for them nor am I trying to lead them to one. This, coincidentally, is one of the points of philosophical discourse.

This question is theoretical and, by modern medical standards, impossible. It was an inherantly meaningless question; philosophical questions are generally meaningless and fruitless. For example:

-Is God real?
-Where did we come from?
-Why are we here?
-Will existence end?

None of these questions have any inherant meaning, their true answers are impossible at the present to determine, and any answers to them are subjective and serve no purpose. Which is why they are philosophical in nature. If there were answers to those questions, then they would be fact based and would be scientific in nature. Philosophy is simply the study of enigma. Which is why this thread is in the philosophy section.

Your answer (and attitude towards the original question), is reminiscent to me of the answer that Heraclitus of Ephesus is supposed to have given. He said that existence is like a river, in that you can step into the same river twice, yet it will be two different rivers. Meaning nothing in existence is ever the same twice as everything is ever changing; everything is, but isn't. I suppose when applied to the ship of Theseus, the ship never truly was the same the moment after it was built.

My question regarding the human mind and the piece by piece replacement of a persons brain cells, however, is if and when the identity of a person (the soul, mind, spirit, etc) ceases to be.

[Taiji]

OK great, thankyou for clearing up the misunderstanding, Ancient.

My question regarding the human mind and the piece by piece replacement of a persons brain cells, however, is if and when the identity of a person (the soul, mind, spirit, etc) ceases to be.

To me identity is a result of observation. The values used in the observing are probably most of what makes up an identity. Essentially a thing would lose it's identity when it ceases to behave in relation to our senses+values in a way that we recognise as being that thing. So with a loose enough definition we can say that they never lose their identity even when they are disintegrated. Or we might decide that, regardless of any change we notice, the thing lost it's identity the same moment we gave it one.

I think in practical terms we expect a person to continue changing and we're loose enough in defining their identity for them to still be themselves even when thoroughly brain damaged. So to remove the person's identity by replacing brain cells, I think you'd have to kill them.

After replacing a load of cells, and a change in his behaviour ensuing as a result, his wife may leave him saying 'he's not the man I married', that kind of stuff happens all the time. She's talking more about her values and expectations than about him. He no longer fits her identity for him in a way that is compatible with the marriage relationship she wants. She probably wants him to be predictable in certain ways, and when she finds that her old predictions don't work, and that new predictions do, she'll decide he isn't who she wants to be married to as soon as the new predictions don't suit her.

[Ancient Aliens]

OK great, thankyou for clearing up the misunderstanding, Ancient.

To me identity is a result of observation. The values used in the observing are probably most of what makes up an identity. Essentially a thing would lose it's identity when it ceases to behave in relation to our senses+values in a way that we recognise as being that thing. So with a loose enough definition we can say that they never lose their identity even when they are disintegrated. Or we might decide that, regardless of any change we notice, the thing lost it's identity the same moment we gave it one.

I think in practical terms we expect a person to continue changing and we're loose enough in defining their identity for them to still be themselves even when thoroughly brain damaged. So to remove the person's identity by replacing brain cells, I think you'd have to kill them.

After replacing a load of cells, and a change in his behaviour ensuing as a result, his wife may leave him saying 'he's not the man I married', that kind of stuff happens all the time. She's talking more about her values and expectations than about him. He no longer fits her identity for him in a way that is compatible with the marriage relationship she wants. She probably wants him to be predictable in certain ways, and when she finds that her old predictions don't work, and that new predictions do, she'll decide he isn't who she wants to be married to as soon as the new predictions don't suit her.

Looking at it externally (from a third point of view) is a very interesting way to approach the subject. Bob1 could have his entire brain replaced, would become Bob2, but Jane (his wife ) would never be able to tell the difference unless she was told of it, and he would still be Bob1 from her perspective.

But what if we look at it from the first person? If Bob1 goes through the procedure, what happens to that identity (soul, mind, spirit, etc)? Does it simply die off? Or is there no change at all from the perspective of Bob?

[Taiji]

Or is there no change at all from the perspective of Bob?

Bob's perspective is changing all the time. Whether he's aware of it or not probably depends first on what Bob pays attention to, and then what changes.

[Armatus]

You can see how those identities change as both Bob's begin to walk their separate ways, kind of like twins their experiences have been different since they were split.

[Col. Tartleton]

Recently I have been applying the Ship of Theseus paradox to the human brain, and further, to the question of human immortality.

Theoretically, if we were to replace a persons (let's call this person Bob for the sake of simplicity) brain, neuron by neuron, with cloned tissue, at what point (if any) would he fail to be Bob and simply be Bob 2.0? Would it matter if Bob was conscious during this process or not? And ultimately, does this question even matter as we will never know the true answer (as the theoretical Bob 2.0 would have the same memories as Bob and would be indistiguishable)?

Going further, I wondered theoretically if the original neurons from the original Bob were used to reform the original Bobs brain, would Bob 2.0 or Bob 3.0 be the true Bob? Or would neither of them be Bob because Bob is simply the electrical current or the chemicals which originally resided in Bobs brain and anything other than these would fail to be him?

Thinking along these lines, if anything less than the cancellation of the aging process all together were to be applied to a human being in attempt to gain immortality, would immortality be impossible due to the possibility of the ending of the original consciousness? Also along these lines; if the brain was to shut down and the electric current in the brain were to cease, would the original consciousness die, even if the brain was restarted?

What are you answers, questions, thoughts, concerns, and/or disagreements?

Im pretty sure every seven years we've replaced every cell in our bodies, so we aren't the same person ever. Every second cells are destroyed and made. We are a composite of many parts. We exist as a concept. I'm not quite sure what consciousness is, but we have it.

[Armatus]

good point, we can only know consciousness through our own process of understanding the and interrupting of the meaning of the shell we're born into.

[Himster]

Theseus' ship remains the same because the formal cause remains the same, it's use is identical (a ship that belongs to theseus). A similar ship could be considered qualitively identical, but that's not the same thing: it's not numerically identical.

[Amorphos]

To op

I think that not only could you replace bobs neurons and all cells with new cloned ones, you could replace them with different ones if you done it gradually enough. How about an artificial diamond neuron replication upgrade!

As long as bob doesn’t go through some duplicating machine, where the old bob is replaced with a new one [as that wouldn’t be bob], then I think you could make all sorts of augmentations and other changes. we could ask if the personality is always bob but does that really matter, the same consciousness would remain ~ its not much different to moving country, being drunk or taking LSD. Personalities are transient. …no doubt form will be so to at some point.

I would rather like wings for a while.

..reminds me of he-man.

[Ancient Aliens]

To op

I think that not only could you replace bobs neurons and all cells with new cloned ones, you could replace them with different ones if you done it gradually enough. How about an artificial diamond neuron replication upgrade!

As long as bob doesn’t go through some duplicating machine, where the old bob is replaced with a new one [as that wouldn’t be bob], then I think you could make all sorts of augmentations and other changes. we could ask if the personality is always bob but does that really matter, the same consciousness would remain ~ its not much different to moving country, being drunk or taking LSD. Personalities are transient. …no doubt form will be so to at some point.

I would rather like wings for a while.

..reminds me of he-man.

Interesting points. I wonder though if there is a grouping of cells in the brain that make us who we are, or if it is the electrical impulses or chemicals that determine what makes us us. I guess what I'm truly wondering is, what is the physical, electrical, or chemical part of the brain that enables us to come to the conclusion that "I am me" and if it were to be altered, would the identity itself be replaced with another one, from the perspective of the identity that is being altered?

Even if you had an exact copy of the chair, it would have a "life" of its own. If the chairs are paired with the same table and go to the same family are they not yet unique from one another? Must they be separated and found new homes? No...

Agreed. You can quantitatively differentiate two identical objects.

[Lupu]

Is a chair really a chair?