What I'm asking is basically how is the "self-awareness allocation problem" solved. I know this problem can be confusing, so let me try to explain it by means of examples:

  • Example 1: Let’s imagine there are hundreds of identical brains spread around the world, and let’s focus on brain A which is located in Mexico and brain B which is located in China. Now, the self-awereness (henceforth, SA) that emerged in brain A is bound to experience life in Mexico, it will never know what it is like to live in China (assuming they can’t travel, for the sake of the example). The reversed can also be said of the SA manifesting in B. But, what prevented the SA that emerged in brain A from emerging in brain B, or from emerging in any other brain for that matter? How is this "SA allocation problem" solved? For example, if you claim that the particular brain where a particular SA emerged is determined by the physical structure of that brain, then how do you solve the case in which all brains are identical?
  • Example 2: Right now you are aware of what’s happening to your brain (leaving the sub/unconscious aside), right? You are watching your laptop’s screen, you are feeling your clothes touching your skin, you are aware of your thoughts popping up in your mind, etc. That’s your current POV (point of view). Right? At the same time, I’m aware of what’s happening to my brain, i.e., I’m watching my laptop’s screen, I’m feeling my fingers touching the keyboard as I type this, I’m aware of my self-dialogue and my thoughts in my mind, my emotions, etc. This is my POV (point of view). Ok? Good …

    Now, image that suddenly our POV’s are SWAPPED. So, I suddenly start to become aware of the sounds around you, your laptop’s screen, your thoughts, your inner dialogue, etc. Likewise, your POV suddenly appears in my brain/body, and you start to become aware of my thoughts, emotions, sounds, touch, etc. In other words, each POV supplants each other’s POV. But everything would still be the same. Instead of your POV being aware of your brain/body actions, now it is my POV that is aware of them. So the next morning when your brain/body kisses your girlfriend, it would my POV being aware of it instead of yours. And when my brain/body decides to feed my cat next morning, your POV would be aware of it instead of mine. In other words, everything would be exactly the same, with the only difference that instead of my POV being aware of what used to be “my” body and your POV being aware of what used to be “your” body, it would be the other way around. One could loosely say that after the swap each POV “believes” to be the other person, although that would not be technically correct as the POV is just awareness, and “believing in something” requires some cognitive processing. In other words, each brain has its own beliefs, personality, etc., which have not changed. The only thing that we are changing in this mental exercise is the location of the POVs. My brain/body would continue living its life and your brain/body would continue living its life, our personalities would still be the same, people who know "you" would still believe that "you" are "you" and people who know "me" would still believe that "I" am "me". Our lives would continue being as they used to be, with the only difference that the POVs which are aware of those lives are now swapped.

Hopefully this made the concept clearer. Now, assuming there are hundreds of identical brains and bodies (in fact, the requirement of identicality is not even necessary), how do you solve this “POV allocation problem”, so to speak?

Notice that I'm NOT saying that one brain can be aware of another brain. That's not what I'm saying. What I'm saying, specially with example 2, is that there is no apparent reason for your self-awareness to be necessarily "attached" to your current brain/body, as we can perfectly imagine a situation in which our awarenesses/POVs are swapped and everything would still be the same (please read example 2 again). However, it turns out that our awarenesses/POVs are in fact allocated in a specific way and not in another. Why is it so? That's the question.

  • Are you asking for an account from a materialistic view?
    – H Walters
    Apr 11, 2018 at 4:26
  • 2
    You are treating "self-awareness" like a substance, if it is simply an attribute, like shape or structure, the problem does not exist. So the problem only arises for Cartesian dualists (a very small group), and is known as the causal pairing problem.
    – Conifold
    Apr 11, 2018 at 4:31
  • 1
    Think of "self-awareness" by analogy to "redness". If they are analogous then your "puzzles" are purely verbal, it is no more meaningful than asking what connects redness of an apple to its apple out of many apples to choose from. If "self-awareness" is not a substance then we are not corresponding two things, we only have one whose properties (adjectives like "red" or "self-aware") are verbally expressed by using fake nouns.
    – Conifold
    Apr 11, 2018 at 5:21
  • 1
    He means simply what you're presuming; that there's a "thing" you can swap between China brain and Mexican brain that has nothing to do with China brain's brain state and Mexican brain's brain state. That "thing", if swappable, must be a "thing in itself" that can have a location (Mexico or China); otherwise you can't say you put the China one in the Mexican brain and vice versa. You're calling that thing here a POV.
    – H Walters
    Apr 11, 2018 at 5:29
  • 1
    This is why Buddhists compare human "soul" to necklace without a thread, see anatman. The problem with both your questions is that you have a wrong idea of what identity through time amounts to, see also the Ship of Theseus.
    – Conifold
    Apr 11, 2018 at 22:33

4 Answers 4


"If two brains A and B were 100% identical, why would A's self-awareness emerge in A instead of emerging in B and vice versa?" Am I missing something? The answer seems trivial. Presumably the question is talking about A and B being qualitatively identical but quantitatively distinct (Philosophy 101). The reason why A's self awareness emerges in A and not B is because brain A is brain A and brain B is brain B and they are two physically separate and distinct biological organs. Why are the processes in my liver going on in my liver and not someone else's? Well, because it's my liver. Have I missed some point?

  • Exactly. Just like you can measure temperature with 2 different thermometers.
    – Probably
    Jul 13, 2018 at 17:25

The reason that you seem to be stuck in a body (which we might call the "subjective justification" for this conclusion) is worth pointing out to help ground the issue.


Since we're adult humans, and especially since it underlies our ability to discuss things in the first place, I'm going to presume we share Theory of Mind (ToM). Breaking this down, subjectively speaking, we appear to have a particular first person view (FPV); I see what I see and you see what I see, but per ToM I don't see what you see and you don't see what I see. From a broader perspective this FPV covers not only sensation but thoughts and planned actions. The fact that I have my subjective FPV, and through ToM project that you have a unique FPV and another individual (say "Joe") has yet another FPV, suggests that there's a separation between my mind, your mind, and Joe's mind; that is, if we get all three "social persons" (living bodies) in a room, then we have as many minds as there are bodies. Let's call this principle "mind separability" (MS).

Now, sensations, thoughts, and actions only cover the "reasonable present". I see my monitor; I am in the process of thinking and typing this sentence, but after about a day I will no longer see this monitor in its current state (that is, tomorrow I won't see what I see today), and I won't experience typing this sentence. But there is another analogous experience that extends into the past... the experience of memory. In particular, the memories I have seem to be about having had a particular FPV perspective. And just as you, myself, and Joe seem to have three different distinct minds, we also not only have memories, but have memories of having distinct minds, and furthermore of having particularly distinct minds associated with those three social persons (living bodies). Let's call this principle "recalled mind separability" (RMS).

Finally, for completion, it's worth pointing out that however far back those memories go, they still seem to share the property that the object of their memories is about having the particular distinct minds associated with our social persons. That is, there's nothing qualitatively different between remembering what I did yesterday and remembering what I did two days ago, in contrast with the qualitative difference between experiencing something right now and remembering something I did yesterday. So let's call this principle "memory permanence" (MP).

Getting back to the subject at hand, MS is what gives us the impression that we're different minds in the first place. RMS and MP give us the impression that we have what I'll term precisely as identities; that we as social persons are individual entities that remain across time. MS, RMS, and MP together also give us the impression that we tend to "aggregate" our experiences across time... that is, there's a "present" where we as individuals have experiences, those experiences seem to be stored in memories, and those memories seem to be "held".

(For the record, MS, RMS, and MP are terms I'm inventing for this particular discussion; ToM of course is a standard term).


Viewed from this perspective, our subjective experience of being a separate identity flowing through time (which is presumed by your questions) can be said to be derived subjective theories based mainly from RMS and MP. RMS and MP are properties of our memories. If we hold a particular modern viewpoint that our memories are a result of brain states, and we also hold the view that our senses are a result of brain states, then essentially it's the state of a particular brain that suggests that we have a POV in the first place, and it's the aggregation of experiences/memories by that brain that's responsible for the RMS and MP that suggests that we're stuck in particular bodies.

From a materialist perspective, our brains are the POV; so scenarios suggesting that our POV's swap are impossible unless you either: (a) physically swap the brains, or (b) put the brains into a blender and carefully reconstruct them into complementary states. Other monisms could similarly relate bodies or body equivalents to minds.

A dualist perspective, OTOH, can be seen (most generally) as positing that there is "something else" that is responsible for a POV. I don't think in discussing dualism most generally, we can describe it any further; you can literally hold anything from the notion that every POV is constantly destroyed and recreated between experiences and that identity is an illusion to the notion that there's only one universal POV and that MS is an illusion.

For this reason I'm going to continue discussing things from a materialist perspective, so you can see what it's like.

Subtleties: A materialist view of identity

At the beginning of example 1, you posit that we start with identical brain states, but you don't describe how those brain states come to be identical. I'll discuss two scenarios in an attempt to give a better idea of identity.

In the first setup, we're going to clone you to make the 100 brains. Let's pick a particular pre-clone time t1 and call you at this time xwd-t1. After the cloning, let's say that xwd-m is in Mexico and xwd-c is in China. Per your own example, xwd-m and xwd-c's experiences will immediately be different; xwd-m only experiences Mexico, xwd-c China. So xwd-m and xwd-c have distinct FPV's; ToM suggests they have distinct minds. (Modern) materialism would suggest their distinct minds is a result of the fact that their minds are a result of their brain state. But both xwd-m and xwd-c share brain states corresponding to "recalled memories" of being xwd-t1; MP suggests they will continue to share these, so they do not feel like they were separate individuals before the cloning. After the cloning, they do. If we take identity itself as emergent, then we would say that xwd-m and xwd-c are different persons, but they were the same person, and this suggests that identity itself doesn't necessarily preserve number (a single past identity xwd-t1 can "become" two identities).

But if you can shove a brain in a blender and recreate it in a different configuration, perhaps you can take some blended brain mass and make your own configuration whole cloth. Suppose you do this and make an entirely new individual... Adam, who you happened to make last Thursday. But you build Adam in such a way that he has memories of being Adam last Wednesday (you need not be "deceptive" about it; you can freely admit to Adam that he has false memories if you wish). Now just as xwd-m and xwd-c each have memories of being xwd-t1 at time t1, Adam has memories of being Adam last Wednesday. The difference here is that there actually was an xwd-t1 for xwd-m to claim he was at time t1, but there was no such Adam. By a similar argument you can say that even if xwd-m and xwd-c happened to share the same experience at some time t2 post cloning, they can only really claim to be the particular referent having that experience (that is, you need a causal connection)... for this reason we would say that each brain has its own mind, and that identity is established through memory, and it can be fake or real under ordinary epistemic criteria (the memories must refer to a real entity and be causally related to it for them to be said to be "genuine").


I can't comment because I don't have any rep, but this question is fascinating to me, and I'm glad someone else is freaking out about it.

One fringe solution might be accepting that moving across brains is ok as long as it doesn't violate certain continuity constraints. This would unfortunately mean that the world has to make an arbitrary choice if this ever happens.

I personally don't buy the argument that spatial position distinguishes the brain states. What happens if we "pause" A and B, then switch their positions and "restart"?

Honestly, I have no idea. But this is a completely valid question.


Emergence is nothing else than a different description of a state that could also be described as other states. Such as describing a glass with a fluid as:

  • It has 50% blue molecules
  • It has 50% yellow molecules
  • All molecules are distributes equally in the glass


  • It's a glass with a green liquid

The question

If two brains A and B were 100% identical, why would A's self-awareness emerge in A instead of emerging in B and viceversa?

thus is the same as qustion:

If two glasses A and B were 100% identically filled with blue and yellow molecules, why would A's green shade emerge in A instead of emerging in B and viceversa?

It does not make any sense to ask that, same as for your brain and Self-awareness question. Emergence is not magic, it is not a creation process, emergence merely means that a state can be described in other words.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .