The question is: even though I'm separated from by an unimaginable distance, — Purple Pond

A different universe does not necessarily mean far from here. It might be occupying the same place.

and we belong to different universes, am I the same person? — Purple Pond

No. You are different people. Separate entities.

No. You are different people. Separate entities. — Sir2u

Why can't separate entities be the same?

Why can't separate entities be the same? — Purple Pond

Because then they could not be separate entities.

Didn't we beat this story to death in another recent thread?

In any event, you would be two different people. It's no different than running the Chrome browser on millions of different computers. There's only one Chrome browser, namely the program code. But there are millions of individual instances of the Chrome browser. In computer science it's the difference between program and process.

Just like the Star Trek transporter. Suppose Kirk beams down to the surface of a surprisingly earthlike planet (saves on production costs for all the alien planets to have breathable atmospheres) but the transporter malfunctions and Kirk also stays on the Enterprise. The cloned version is identical to Kirk at that instant. But going forward, they are two distinct people having distinct life experiences.

For a more prosaic and commonplace earthly example, consider identical twins. A fertilized zygote splits into two. You now have two individual human beings developing from the same program code as it were.

Didn't we beat this story to death in another recent thread? — fishfry

Do you think you can provide a link?

Because then they could not be separate entities. — Sir2u

Your going in a circle. But never mind, I agree, two separate entities are different things.

Do you think you can provide a link? — Purple Pond

You're right, it wasn't that recent. Time flies like an arrow. Fruit flies like a banana. Twelve pages worth starting here. Although to be fair, OP's question in this thread is different.

https://thephilosophyforum.com/discussion/2408/level-iii-multiverse-again-/p1

In any event, you would be two different people. It's no different than running the Chrome browser on millions of different computers. There's only one Chrome browser, namely the program code. But there are millions of individual instances of the Chrome browser. In computer science it's the difference between program and process. — fishfry

Are human beings like a process? If so, what would be analogous to the single "program code"?

Are human beings like a process? If so, what would be analogous to the single "program code"? — Purple Pond

DNA perhaps. Although you could say that DNA is more like a programming language so that's not a great example.

The analogy I'm trying to get at is that at the moment of cloning/replicating, you have two individual humans who have the same memories and experiences. Their experiences immediately start to diverge.

But whatever it is that makes us human, we all share that. We're all expressions of that. DNA isn't the best example.

The analogy I'm trying to get at is that at the moment of cloning/replicating, you have two individual humans who have the same memories and experiences. Their experiences immediately start to diverge. — fishfry

Two humans with different memories and experiences must be different people. Got it.

Suppose that there are an infinite amount of universes and that everything that can happen does happen in some universe. So there's a universe just like ours with a planet identical to earth (lets call it earth-2), and everything on earth-2 is identical to earth to the last atom. So there's a Purple Pond user just like me typing this thought experiment. I'm atom for atom identical to the Purple Pond on this different universe. The question is: even though I'm separated from by an unimaginable distance, and we belong to different universes, am I the same person? — Purple Pond

This question was solve by Leibniz in C17.

https://plato.stanford.edu/entries/identity-indiscernible/

Two humans with different memories and experiences must be different people. Got it. — Purple Pond

Well if they're two humans then they're not one human. So your statement's a bit unclear.

If a human is cloned, that results in two different people who shared all experiences, inner and outer, up to the moment of cloning.

If they live in different universes, they are different humans even though they always have the same experiences. After all they are made of different atoms that exist in different universes. That must be so, no?

So having different experiences is sufficient for there to be two distinct people; but not necessary.

But the idea that there are two universes that are identical seems a little different from the usual conception of the multiverse, in which each universe represents a different state of matter. Does multiverse theory allow for identical yet distinct universes?

Well if they're two humans then they're not one human. So your statement's a bit unclear. — fishfry

You can talk about two things that happen to be one, like Hesperus (the evening star) and Phosphors (the morning star). Both of which incidentally turns out to be Venus. https://en.wikipedia.org/wiki/Hesperus

If a human is cloned, that results in two different people who shared all experiences, inner and outer, up to the moment of cloning. — fishfry

When did the cloned person come into existence? If it's the moment of cloning then he couldn't have shared all the experiences up to the moment of cloning.

But the idea that there are two universes that are identical seems a little different from the usual conception of the multiverse, in which each universe represents a different state of matter. Does multiverse theory allow for identical yet distinct universes? — fishfry

I don't know. I guess it's logically possible.

I started reading it until they started talking about "intrinsic" and "extrinsic" properties. I couldn't read anymore. :s

You can talk about two things that happen to be one, like Hesperus (the evening star) and Phosphors (the morning star). Both of which incidentally turns out to be Venus. https://en.wikipedia.org/wiki/Hesperus — Purple Pond

That's an example of two different names for the same thing. But under the assumption of the multiverse, these are two distinct, separate universes containing separate piles of atoms. So any two creatures in the respective universes must be distinct creatures, even if they are atom-by-atom or even quark-by-quark copies of each other. Isn't that the basic assumption here? If the universes are disjoint, they can't have any objects in common.

I'll add that this common example of the morning star and the evening star is ironic, since Venus isn't a star.

When did the cloned person come into existence? If it's the moment of cloning then he couldn't have shared all the experiences up to the moment of cloning. — Purple Pond

I suppose if the cloning operation takes a small interval of time, we can talk of the experience of the cloned pair being identical before the cloning operation takes place and beginning to diverge after, with the during-cloning-operation state being indeterminate. Nobody knows what you experience when you're being cloned.

...am I the same person?

What do you mean by "person"? Are you asking if the two bodies are the same body, if they are in fact not distinct after all, being one body? A is A? Or are you asking something more along the lines of whether there are two different subjects, two different experiencers?

If you are talking about the bodies, if they are defined as distinct and if there is some way to finally distinguish them, some way to show the two universes to be distinct, then I guess they are distinct, in which case they can't be the same body. If A is not B, then A cannot be B. If A is A, A cannot be other than A.

But if they are truly indistinguishable, by the identity of indiscernibles, it would seem that it makes no sense to say that there are two separate things. If two universes are perfectly identical in every possible way and there is no way to tell the difference, how can they be said to be different? Are they separated somehow, say spatially? I'm not sure what a spatial separation between universes would mean, but in that case, they wouldn't be identical. There would be at least one difference, namely, that of location.

If you are getting more at the subjective experience and perspective, then I'd say definitely yes. That which fundamentally has the experiences finds itself being both people. You, the real you, inhabit both universes. But there is nothing particularly special here about the fact that the two bodies are identical and yet distinct. You, the real you, also find yourself being everyone and everything else. You are me as well. You find yourself occupying every perspective.

There is only one real self. There are no truly separate individuals. The illusion of separate selves is the result of incomplete information integration between different parts of the world.

we can talk of the experience of the cloned pair being identical before the cloning operation — fishfry

But there's is no cloned pair before the cloning process has begun. There's only one person yet to be cloned.

You are me as well. You find yourself occupying every perspective. — oysteroid

I find that hard to believe.

Suppose that there are an infinite amount of universes and that everything that can happen does happen in some universe. So there's a universe just like ours with a planet identical to earth (lets call it earth-2), and everything on earth-2 is identical to earth to the last atom. So there's a Purple Pond user just like me typing this thought experiment. I'm atom for atom identical to the Purple Pond on this different universe. The question is: even though I'm separated from by an unimaginable distance, and we belong to different universes, am I the same person? — Purple Pond

This is the kind of question that gives philosophy a bad name. Silly hypothetical situations that are probably not possible and very probably not knowable if they are possible. And in the end, it all comes down to word play and semantics.

Also, if there are an infinite number of universes, it is infinitely unlikely we are on Earth-1.

I'm sorry that you found my question silly. Maybe fishfry's example of a cloned human may seem less fantastical.

Also, if there are an infinite number of universes, it is infinitely unlikely we are on Earth-1. — T Clark

It would also be equally unlikely that we are on another planet. In an infinite multiverse everything that happens will be extremely unlikely. But just because something is unlikely doesn't give you justification for believing it's not true. Unlikely things happen all the time.

It would also be equally unlikely that we are on another planet. In an infinite multiverse everything that happens will be extremely unlikely. But just because something is unlikely doesn't give you justification for believing it's not true. Unlikely things happen all the time. — Purple Pond

It isn't unlikely, it's infinitely unlikely.

This is the kind of question that gives philosophy a bad name — T Clark

It gives physics a much worse name. There are people who take this idea seriously. https://en.wikipedia.org/wiki/Multiverse

But there's is no cloned pair before the cloning process has begun. There's only one person yet to be cloned. — Purple Pond

Right ... and the clone is a new person identical (for a brief period of time, before the clone's experience starts diverging) to the original, right? That's what I mean by the cloned pair. I'm confused as to why this conversation got so confusing.

It gives physics a much worse name. — fishfry

I don't know why you would say that, science has long known about Mister Mxyzptlk, the imp from the 5th dimension.

It isn't unlikely, it's infinitely unlikely — T Clark

We don't have to be on earth-1 we could be on any earth.

I'm confused as to why this conversation got so confusing. — fishfry

I don't know why either. Maybe end it here before it gets even more confusing? >:O

It would also be equally unlikely that we are on another planet. In an infinite multiverse everything that happens will be extremely unlikely. But just because something is unlikely doesn't give you justification for believing it's not true. Unlikely things happen all the time. — Purple Pond

As I mentioned in another thread, many of the most eminent cosmologists claim that something like this situation obtains: there is an infinite multiverse where all physical configurations consistent with the conservation laws exist. They do this because it is a deduction from the best candidate theory of the creation of the our universe.

You have got to be a bit careful when using probabilistic language to talk about the multiverse. While it is the only way to talk about and analyse the grand ensemble, nothing probabilistic physically occurs in the multiverse.

As I also mentioned in the other thread, there is no evidence for this cosmological multiverse, yet it is the one most people are quite willing to accept. On the other hand, there is overwhelming evidence for the quantum multiverse, yet this is supposed to be controversial. I find the psychology of this situation utterly bizarre. To add to the irony, if the cosmological multiverse exists, the quantum multiverse adds zero complexity to our view of reality. Very odd situation!

Interesting points.

Anyways, back to the OP. Everyone agrees that they are different people (including me). So there's no point of discussing it anymore, unless you want to talk about something else.

As I also mentioned in the other thread, there is no evidence for this cosmological multiverse, yet it is the one most people are quite willing to accept. — tom

I'm not willing to accept it unless there is ample evidence. I was just talking hypothetically in my OP. It's fun to talk about cosmilogical multiverses, even if there's no such thing.

On the other hand, there is overwhelming evidence for the quantum multiverse, yet this is supposed to be controversial. — tom

Really? I thought the MWI of quantum mechanics was just that - an interpretation.

Anyways, back to the OP. Everyone agrees that they are different people (including me). So there's no point of discussing it anymore, unless you want to talk about something else. — Purple Pond

Everyone apart from Leibniz and everyone who agrees with him, oh, and physicists who understand indistinguishability and its consequences.

Really? I thought the MWI of quantum mechanics was just that - an interpretation. — Purple Pond

Many Worlds is a physical theory. It is quantum mechanics with no collapse. We routinely interact with the other worlds - in quantum interference experiments, interaction free measurements, via quantum entanglement, superposition, and most remarkably when we perform quantum computations.

Here's an interesting video that's relevant.
This too.

I find that hard to believe.

I realize it is a strange idea that I am asking you to consider. Bear with me a bit and keep an open mind and consider the following. It is long, I know, but I don't know how else to get this across. If you get what I am trying to communicate, I think you'll see that it neatly solves all of the many puzzles of personal identity is a possible solution almost always left unconsidered.

Have you ever wondered why you find yourself being the particular person you happen to find yourself being? Don't look at it from an objective standpoint. Look at it from a subjective standpoint. Ask yourself, "Isn't it a little odd that I happen to find myself being Purple Pond and not someone or something else?"

First, consider that having a subjective perspective and being someone isn't an objective state of affairs. If you were to restrict yourself to third-person language and describe the world, there is one thing you couldn't declare: which of the entities in the world you are. You could say things like "Purple Pond is sitting in a chair looking at a screen" or "Oysteroid is wearing a white sweater" or "Purple pond says that he is Purple Pond". You couldn't say "I am Purple Pond." Finding yourself as a particular person, occupying a particular perspective, is something other than an objective fact, something that reveals itself to be more than a little mysterious if you think about it for a while.

What are the odds that out of all of the 3 pound hunks of matter out there in the vast universe or maybe even infinite multiverse, most of them lacking biology, you just happen to find yourself being a human in this special place and time? Did you win the cosmic lottery a hundred times over or something? Shouldn't you find it a bit surprising that you find yourself occupying such a privileged vantage point on the world? After all, it seems, you might have been a mouse instead, or a bacterium, or a cloud of dust or a rock in outer space.

Suppose we have a big bucket filled with a trillion marbles, one of which is gold, the rest of which are blue. We blindfold you and have you dig around and withdraw a marble. Then we ask you whether or not you should expect to take off the blindfold and find yourself holding a gold marble. Of course, the answer is no. With a random sample, you should expect to have a typical sample. If you do end up finding yourself with the one in a trillion golden marble, shouldn't you find this surprising?

Now consider how rare life is, how rare brains are, as far as hunks of matter go. Even as far as brains go, human brains are extremely rare. Even if the only thing it is possible for a self to find itself as is a human brain, isn't it weird that you are this particular one, and not another? What is it that determines which vantage point on the world you have?

From an objective perspective, of course Purple Pond is Purple Pond! How can it be otherwise! A is A! But that ignores the issue. The issue is your subjective perspective and your being someone.

People say, "I am my brain." What does that really mean? They are connecting something, their 'I', to something else, a particular brain, and saying that A is B. Isn't this a bit odd? What is this 'I'? To be a truly separate individual, it is as if you have your own 'I' and I have another one, as if each brain has a unique 'I' associated with it. But this idea, resembling the old individual soul idea, just adds mystery to mystery. Suppose you are a soul, even if you don't believe in such things. Why are you this soul and not a different one? Same problem. And on you would go with an infinite number of homunculi within homuncili.

Consider further what a strange idea it is that you can be something, some arbitrarily extended, but limited, collection of physical particles. People sometimes ask what it must be like, if it is like anything at all, to be a rock. Notice what they are doing! Is there some magical boundary around a rock other than the one we impose when we see a rock and identify it as such, mentally separating it from its surroundings? If a rock, which is a collection of many smaller things, why stop the collection at that point? Why not a pile of rocks? Why not the mountain? Why not the planet? Why not the whole universe?

But isn't it strange that you could be a collection of things in the first place? Let's simplify this so that the issue becomes more clear. Suppose you were to find yourself being a thing that is composed of exactly two things, perhaps two quarks. How can you be a pair of things? Isn't that a weird idea? How is it that you have this span, that what you are can extend beyond just one thing to include more?

Gilbert Ryle used to talk to his students about the question of whether there are three things in the field, two cows and a pair of cows. This makes me chuckle.

When people claim to be a brain or a whole body or whatever, they are saying that they are a huge collection of things, that their identity has this incredible span. Why not half the brain? Why not a single neuron? Why not two brains? Why not everything?

And then you get into all the usual problems of personal identity. Are you the same person over time? But the atoms in your body are changing. The form is changing. Whether you are the very atoms or the pattern in which they are arranged, this creates problems.

If what you actually are is this particular, arbitrary set of particles that currently composes your brain, then after a while, you become dispersed and might end up being split up over multiple bodies as other creatures eat the matter that once composed your body. And if you are these specific particles, realize that they were once separated and belonged to many different organisms. What are the odds that the collection that is you just happened to come together in one brain, all at the same time?

No, you couldn't simply be identical with this collection of atoms! What about the form, the pattern? If you are a particular pattern, consider that the form is constantly changing! You would only exist momentarily! There would be a succession of many, many separate selves, each living a moment in the course of a life.

That doesn't make sense either, does it? So what are you? Consider that you already accept, if you believe that you are a brain or a body, that what you are spans multiple things. It involves multiple particles, multiple cells, multiple organs, a span of time with many states, and so on. It is just that you think that what you are ends with your skull and your birth and death. But why would it end there? Is that some kind of magical boundary that encapsulates an ego? Does a skull boundary define an 'I'?

I think we tend to find it easy to accept that we are a brain, and to not notice that we are thinking that we are a multitude, because of the fact that, because of how our minds carve up the world into things, we think of the brain as one thing, like Ryle's pair of cows.

And then you can consider all the questions that arise with teleporters and the like. If we read all the information describing your body, destroying your body in the process, and then assemble a copy at a distant location, when the person steps out of the teleporter, is that person you? Do you, the same you that you are now, find yourself then on the other side? What if we make two copies? Which one will you be, if any? Or did you die?

How do you know that your form propagating from moment to moment isn't just like that teleporter? Is the experiencer of your perspective this moment the same one as an hour ago? I would say yes, obviously. Otherwise you couldn't experience the flow of time. Your identity must span time in order for you to experience change. And your identity must span some space and material in order for you to have a unified experience of all that your brain is doing, even to experience an apple as an apple, with its combination of color, shape, meaning, and so on, the processing of which involves many brain regions.

So you already have span, both temporal and spatial. You are already more than one thing and more than one state of those things. So why do you think that what you are is limited to this body and its lifespan?

Consider how the idea that you are simply that which is everything, that it is all one and you are it, would solve all of these problems in one fell swoop.

Why do you find yourself being Purple Pond? Well, being everyone and everything, you'd naturally expect to find yourself being Purple Pond. Consider the marble picking again. If you were allowed to hold all the marbles, should you be surprised to find yourself holding the golden one?

Think about it probabilistically. If you are in one of two scenarios, with you not knowing which, and you had to guess which one you are in, which should you bet on, the one in which your case is far from typical or the one in which your case is typical or even inevitable? For example, suppose we flip a coin and determine which of two prizes you get: A, all the marbles, including the golden one, or B, just one marble selected at random. Now suppose that before we tell you the result of the coin flip, we tell you that you definitely have the golden marble. Which should you expect to be true, that the coin chose A or B? You should guess A. In that case, having the golden marble is something you'd expect. In the other case, it would be a big surprise.

The fact that you find yourself being Purple Pond, being a brain at all, being alive at all, being in an inhabitable universe at all, and so on, is absolutely inevitable if you are everything, and astronomically unlikely if you are just one arbitrary three pound thing on a particular arbitrary planet, in a particular arbitrary galaxy, and so on.

Think about a lottery win. If you describe the situation objectively, it is not very surprising when someone wins. But if you find that you are the winner, that is a different thing, isn't it? That is surprising! But notice that it suddenly ceases to be surprising, even subjectively, if you happen to be everyone.

This idea even clears up all the confusion about the anthropic principle and the fine-tuning of the cosmos and whatnot. Why does the universe seem so fine-tuned? Suppose there is an infinite multiverse containing all possible universes. In one of them at least, these conditions will prevail. And if you are everywhere, naturally, you should expect to find yourself alive in a universe fine-tuned for life! But if you aren't everything, if you are just one arbitrary three pound hunk of matter, inexplicably having both span across a multiplicity of things and a limit to that span, then your situation is indeed unusual and suprising to find yourself in.

But there is a natural objection to all of this. Why don't you feel yourself being me and everyone else? Why don't you know that you are everyone? Why can't you access my memories?

There are some famous cases in which people with severe epilepsy have undergone a procedure in which the corpus callosum in their brain has been severed, effectively isolating the two hemispheres. If you aren't familiar with this, I'd suggest researching and reading about split-brain surgery. What results from this is a situation in which it seems that there are now two selves, one for each hemisphere. Using clever methods, you can ask one hemisphere a question and give it information while avoiding giving any information to the other. You quickly find that if you ask one hemisphere questions about what you have only shown the other hemisphere, the answers contain no information about it. You can show that there is no integration of information between the hemispheres. Further, the two hemispheres seem to have distinct desires, distinct plans for the future, and so on. And sometimes, one hand will try to button up a jacket while the other tries to keep it unbuttoned, and so on. Suddenly, it seems that there are two people in one skull, each controlling half the body.

What has happened here? Can your self, the very you that you are, be divided into two? If you undergo such a procedure, which of the hemispheres will you find yourself being afterwards?

Consider another hypothetical scenario. We take a guy named Bob, who is an amnesiac who cannot remember new information for longer than a few minutes, and we place him in a room with a chalkboard mounted on the wall. We show him things, give him experiences, and he records what he observes on the board. When we ask him what we have told him or what he has experienced, he consults the board. It basically serves as his memory. Now, suppose that we take him to a second room, room B, also with a board. But this board is blank. In this room, he does not have any access to what he wrote on the board in room A. We can replicate all the experiments from the split-brain studies using Bob in these two rooms, and we can show that there is no information integration between the rooms. In room B, Bob cannot give information about what he observed in room A, and vice versa. And he can't connect things observed in the two rooms.

Obviously, we can't conclude from this that there are two separate people here, one in room A and one in room B. Bob is one person regardless of the inability to integrate information between the rooms. The only issue here is that there is no way for information to pass from room A to room B and vice versa. While in room B, Bob knows nothing of his life in room A. He doesn't remember being in room A. He might have written a concerto in room A, but he would know nothing of it while in room B. If we give him a portable notebook, he might then integrate information between the two rooms, but without such a device, there is no reason to expect him to have access to information in the other room. The same goes for the two hemispheres in the split-brain. The corpus callosum is like a notebook allowing information to pass between hemispheres.

What's the point of this Bob business? I'd suggest that the very same situation holds for us as seemingly separate individuals. Our two brains are like the two rooms. There is one experiencer with both perspectives simultaneously, but over there, in your brain, there are obviously no memories from my brain. How would they get there? They'd have to get there by some local physical mechanism. In this brain over here, I lack access to what is stored in that brain over there. In the Oysteroid brain, I find no Purple Pond memories, naturally, and vice versa. And that's all there is to it. That's why we think we are distinct selves. In actuality, I believe, that which we are, that deepest inner witness that looks out from behind these eyes, is everywhere and is everything. And it isn't a separate self inhabiting the multiverse, as if there is one big soul assigned to one big multiverse. No! It is all just one whole. Your very self is the very substance of it all. The scenario with Bob isn't a perfect analogy here, as Bob is separate from the rooms.

There is one substance and it experiences all of its modifications and relations and is everywhere present to itself. And if you want to know what it is like to be it, just ask yourself. You're it. You're everything.

It isn't like reincarnation, where you can look forward to another life. No, you are living them all simultaneously and always. You are already over here, experiencing my life. You are already beyond the life of Purple Pond. You just can't access this information from there. While in that room, you don't know that you are also in this room and all the other rooms.

Take this seriously. Think about it. And realize that there is never again cause for envy. When you see someone else enjoying some life that you don't have, know that you have it, that you are that person. Also know that when you hurt another being, you are hurting yourself. It is none other than you that has the experience on the other side of whatever you do to another.

If you have made it to the end, thanks for giving all this your consideration!