Who’s who after a brain transplant? Where does identity reside?
Let’s imagine two women: Millie and Bonnie.
Millie has a body-wasting disease. Her body is slowly breaking down, organ by organ. The only organ which is untouched is her brain. However, the body that supports that brain is deteriorating, and she is near to dying.
Bonnie is a healthy person who suffers an unfortunate accident. She takes a sharp blow to her head which damages her brain, killing her instantly, but leaving her body intact and healthy.
Due to the magic of non-existent futuristic medical technologies, doctors transplant Millie’s brain into Bonnie’s body.
Who is the resulting person? Who is walking around? Is it Millie because it’s her mind, or is it Bonnie because it’s her body? Or is it someone else?
For legal purposes, we identify a person by their physical attributes: fingerprints, retinal patterns, dental history, face. According to that methodology, this person is Bonnie, because she has Bonnie’s physical attributes. If she used Bonnie’s passport, she would be able to travel because her face and fingerprints match the photo and fingerprints in the passport. She would be accepted as Bonnie.
However, this person does not have any of Bonnie’s knowledge or memories. She remembers Millie’s life and friends and education. If we asked her to sit an academic exam about a topic that Bonnie learned, she would fail, but she would pass an exam about a topic that Millie learned; she is therefore entitled to use Millie’s academic qualifications as her own. Her encephalograph would show Millie’s brain patterns. She would recognise Millie’s family and friends.
If Millie and Bonnie each committed a crime before the transplant, should the post-transplant person be held responsible for either crime, or both, or neither? If she was in court, a witness would identify her as Bonnie, who was at the scene of one of the crimes. However, she would not remember committing Bonnie’s crime, but would remember Millie’s crime. Can she be held responsible for a crime she doesn’t remember committing (that brain is now dead)? Can she be held responsible for a crime noone saw her commit (that body is now dead)?
So… who is she? Is she Millie or Bonnie, or is is she some new composite person: Minnie?
Partly inspired by a couple of science fiction works:
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'I Will Fear No Evil', by Robert A Heinlein
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The Star Trek DS9 episode 'Dax', by Peter Allan Fields and D.C. Fontana
Millie - but in an emotional, viscerally confusing way for Bonnie and her loved ones.
Culpability goes with the brain.
I think the law would struggle with catching up to this premise, but it would have to.
That said... it opens new legal issues. What if I have a medical record showing my brain is not my own (but I just paid really well and even underwent the process - without a swap). This would be a way to dodge culpability and EEGs would have to start getting involved - or similar.
I'm not a lawyer, but that's the way I'd expect it to play out.
If culpability goes along with the brain, and we assume that a brain is a result of it's prior experience (perhaps some would disagree) could a technique for erasing memories be a reasonable method for extreme criminal rehabilitation, say, in lieu of the death penalty?
I think this would be technically VERY difficult. But since we're suspending a lot of that here... let's see where my thoughts go.
I think prior traumas can shape people. Some bounce back, some aren't as fortunate (and I don't put that all o them). As a practical matter, if I were a judge, my job is do protect society - now and in the future. Extreme sentences aren't a protection - they are a violence on the family. Light ones, may expose society to unnecessary harm.
I'm not sure, short of significant study, how removal of trauma memories could impact that. At some point, I'd expect memories (good or bad, spoiling or overly hostile) to be encoded in the personality. In how a person copes, in how they respond to threats.
I suppose this, coupled with behavioral therapy, could be a huge win.
IF, and I mean a very thoroughly researched IF, they consent and it's not coerced. They'd have to have sufficient faculties and go in clear eyed about what they're getting into. Ethically, this is a huge minefield.
Edit: I, almost always, oppose the death penalty. It needs to be particularly violent and with complete certainty. And even then I waver.
But... I can see it even for non-violent crime - such as treason.
It's just a hypothetical, for sure, but it sounds like a good premise for a Black mirror episode. The ethics of such a technique are very interesting to consider, how about airborne nano-machines designed to reprogram dissonant memories to keep everyone happy all the time no matter the circumstances.
There was a Black Mirror episode where a murderer's punishment was to have her memory wiped every day and relive the same day over and over while being observed by members of the public treating her like a museum exhibit.
A Clockwork Orange is similar in that it deals with morality and how human are we if our actions are dictated by others, but the book 1984 is a bit closer in how the brainwashing is done until you truly believe in the Party. Still not the exact same premise, though.
There's actually quite a lot of debate in the scientific community about what constitutes cognition. A recent interesting idea, if somewhat vague is "embodied condition". They claim that the brain, while important, is not the only resource we have available to us to generate behaviour. Instead, the form of our behaviour emerges from the real-time interaction between a nervous system in a body with particular capabilities and an environment that offers opportunities for behaviour and information about those opportunities. The reason this is quite a radical claim is that it changes the job description for the brain; instead of having to represent knowledge about the world and using that knowledge to simply output commands, the brain is now a part of a broader system that critically involves perception and action as well. The favorite example given to demonstrate this duality is "the outfielder problem", which dissects the way a baseball outfielder catches a ball - a magnificently complex computational problem. They claim that part of the computation down to catch the ball is done in the muscles (a sort of muscle memory).
By this reasoning (and I myself am not sure I'm sold on it yet) a brain switching bodies will affect the brain just as much as it affects the body, resulting in a third person altogether. They are currently conducting experiments of such hypothesis using virtual reality in which they place a person in different bodies (including, amusingly enough, that of Kafka's cockroach)
I read that as well and can only agree.
On a chemical level, our "self" is not just the brain but the combination of all biochemical reactions that happen in the balance of our whole body (some parts more relevant than others). Definitely the whole nervous system play a big role. You don't just switch brain and get a new glove for it.
The resulting person would be a new one.
This makes a lot of sense to me. A large part of your driving ability is determined by the vehicle. It stands to reason that switching to a new body will result in different responses - for a start, your eyes will see differently, your nose will smell differently and your muscles will respond differently. This won't be an instant transition - quite a lot of physiotherapy would probably be needed, for a start.
A third person, though? Perhaps, eventually. More like changed, not totally different. My morals and tastes aren't going to be affected.
You use the example of a baseball player. If Bonnie was a baseball player (and Millie was not), are you implying that the post-transplant woman formed from combining Millie's brain and Bonnie's body would know how to play baseball?
Does the fact that the post-transplant woman know how to play baseball mean she is neither Millie nor Bonnie, but Minnie? Does identity reside in someone's arm? What if it's only Bonnie's arm that's transplanted on Millie's body? Does the arm know how to catch a ball? Does that change Millie's identity?
I don't think @moriarty is saying that identity is encoded in the body, but that identity is affected by the body that it's in. Like @Stone-D said, if I drive someone else's car, I will drive differently. If I get in a racecar, I will drive poorly since it's not at all what I'm used to, and while it is able to perform races, I am not, and together I'll have to practice in order to know how to race. But it will be easier to learn how to race in a racecar than in my streetcar.
But your identity is affected by everything you do, day to day, year to year. You've had experiences in the past 10 years that have affected you. You've been in various situations, you've learned new knowledge.
If we take a woman's brain and put it in another woman's body, that will certainly affect her identity in the same way as any other new experience. However, we don't cease identifying you as you just because you have a new experience.
Exactly!
Somehow we've come around to the same understanding through some miscommunication or something, it would appear. :)
You & I might agree that someone's personality might be affected by their experiences, but I still don't agree with @moriarty's statement that a hypothetical brain transplant would "result in a third person altogether". There's a difference between the colloquial statement that "I feel like a different person than I was 20 years ago" and "I have a different identity than the one I had 20 years ago". Even though my personality has been shaped by 20 years of experiences, I'm still me (and you are still you).
Maybe I shouldn't have copied your usage of the word "identity" to mean "personality". That seems to have confused matters.
we dont people treat with massive body changes as a different person. why suddenly start doing that?
I think I'm being misunderstood here. That's on me for poor explanation. I agree with you; someone with a new body or a massive change to their body is the same person, it's just that their identity will be affected by the change, not that their identity will change into a different, new identity.
I think what embodied cognition claims is that yes, part of your identity does reside in your arm, in the reflexive way it knows to catch a ball. And while the new Millie might not be a baseball player, hey body would be more familiar with it. The baseball example boils down to print yourself in a position to minimize computational complications when performing a task (like catching a ball). As I said, I'm not entirely sold on the idea, but it's one worth exploring
I think articles like these citing opinions of psychologists and philosophers would be great content for a philosophy posting.
I think legalities are completely separate from the practical reality of the situation. I don't think there's any doubt that the Bonnie is dead and Millie is still Millie in a practical sense. All the legalities hinge on the law being aware of the swap. Legal records get the name attached to them changed all the time, so that's not really an issue unless the swap is done without informing the authorities. As APassenger says, the law would have to catch up.
An idle curiosity that would get a more complete response... if we could do as OP proposes, I think the whole qualia discussion would be given a more complete data set.
Even so, I don't expect that my red is so different from another person's red, assuming approximate match of rods/cones and quality.
Nonetheless, I expect differences. Whether because of differing microbiomes, body needs, somatosensory experiences... this wouldn't be invisible and the brain would have to adapt to more than just new neurons.
What if the post-transplant woman you're calling Millie uses Bonnie's ID to withdraw money from Bonnie's bank account? Is that a crime?
Is she knowingly misrepresenting herself? I would say yes, and it is a crime. It's no different from using your twin's ID to steal their money. Again, this situation is only possible if the transplant is hidden from the authorities. Bonnie should have been declared dead.
What if she doesn't believe she's misrepresenting herself? "This is my body now. It's part of me and I'm part of it. I am this woman in this passport."
Why is Bonnie dead, though? She's up & about, walking around like a living person!
If your brain was scooped out of your body and discarded, you are not alive. If the authorities are aware of what happened, you are not going to be legally alive either.
People who get organ or face transplants aren't entitled to any fraction of the donor's estate. Getting 100% of their body sans brain still doesn't entitle you to their estate.
Millie knows her name isn't Bonnie. She knows she didn't deposit money in the account with that number. If she really thinks of herself as Bonnie, then she's delusional, which may be an expected side effect of such a drastic procedure, but that in no way affects the legality of her actions, except to possibly claim insanity as a defense.
You might be interested in watching Altered Carbon on Netflix. Pretty much the entire show deals with this kind of conflict.
It's on my ever-increasing "one day I'll get around to it" viewing list.
Altered Carbon explores this idea somewhat. Your consciousness resides on a chip which can be implanted in any 'skin', which is the term used to describe everything else. If you go to prison, only your chip is incarcerated - your body is put into a first-come-first-serve temporary loaner pool for those whose original bodies have become unusable for one reason or another and they can't afford a replacement. Near the beginning of the series there's a super brief scene where a family reunites with their young daughter who is currently inhabiting an ~80 year old body. The protagonist is a veteran from a war that took place centuries ago and the 1% are all immortals with access to clones.
It's a great series but I'm not really convinced by the ending. Felt rushed.
The pacing was a bit off - I suspect that was due to the amount of world building that was needed. Considering everything else, I'm giving it a pass and looking forward to season 2.
When I was young I thought about this for a long while. After I learned programming, I came to the conclusion:
It does not work.
It's like in computer programming when you create instances of two classes, now you put one's
thispointer to another. How does this work?It only works if both of you happens to have the same "parent" class. e.g. if you transplant brains between twins or clones.
I mean you're basing this off of what exactly? We haven't done a successful brain transplant yet more due to lack of knowledge about the brain and lack of fine grained surgical needs with all the small nerves and capillaries, etc.
Based on "self-identity" and "consciousness".
Just combining the body and head does not give you a living person. How to transplant "consciousness" is the key.
Well yes but given that it's an emergent property contained in the brain chances are, you move the brain you move the consciousness. For now.
What if we take this a different direction with regards to programming? Say, I have a Human class that has Brain, Organs, Body, etc... members. Now, I have Bonnie, a Human instance with unique Brain, Organs, Body and I have a Millie instance with unique members. If I were to do an operation like Bonnie.RemoveBrain, now Bonnie has a null Brain. Then, I do Bonnie.AddBrain(Millie.Brain). At this point, the Bonnie object now returns true when calling IsAlive. So, we have now replaced Bonnie's Brain with Millie's Brain and the Bonnie object is "Alive".
Let's take it further. Human.IsAlive returns a value true or false, let's write a bit of psuedo code for the next part:
So, now Millie's Brain is reporting if itself and the organs/body attached to it are alive. The Brain, Organs, and Body now all "belong" to the Bonnie object even if they didn't originate from the Bonnie object.
All that said, I don't think code architecture or programming functionality alone provide the answer to this situation.
Well I dont think there's a
IsAliveproperty for human, human are alive as long as he/she has consciousness. It's the same reason why Windows/POSIX does not have a system API called "IsComputerPoweredOn"For human brain, it's not the physical brain that matters, it's the mind that running it. For example, if you wipe a person's memory completely (some kind of format & reboot), then you got a completely different person, even with the same brain, limb and organs. Consciousness is kinda like a Factory class, it generates different traits. For most people, it's a singleton. For people with multiple personality disorder, you got multiple
thispointer.Just my theory. lol.
This sounds to me like an incomplete version of the ship of Theseus. What if you only replaced one damaged part of Millie's body at a time? Replacing a finger, her hand, her arm, maybe her legs, eventually her torso and even her head, just a single part at a time over the years until none of her original body parts remain except her brain.
Would we then conclude that she's a different person? Certainly not. We would still agree that she's Millie despite the change in body and biometric identification (e.g. fingerprints). The only difference is that this change is gradual and could source body parts from several people vs. the proposed instantaneous change from a single body source.
Furthermore, the body is merely a vessel which provides the inputs necessary for identity to develop. Once the brain switches bodies, the identity remains the same, it's just the inputs that differ. The switch therefore does not alter identity, but alters how that identity will develop and experience the world moving forward.
I considered mentioning the ship of Theseus in my post, but decided to just stay focussed on the hypothetical situation itself.
Here's a follow-up question that occurred to me after posting this:
What if the post-transplant person takes Bonnie's ID into a bank and uses it to withdraw money from Bonnie's account? Has she committed a crime? Is this equivalent to fraud? Is she an imposter? It's not like she stole Bonnie's identity or forged her passport - for all intents and purposes, she is indistinguishable from the woman photographed in the passport.
For this I would refer you to twins. If I have an identical twin and I put on their clothes with their ID in the pocket, and I use that ID to withdraw funds, I am stealing. Even though we have (effectively, for this example) the same body, we are not the same person.
But the post-transplant person owns (for want of a better word) Bonnie's body. She's not pretending to be anyone else - this is her. Not her twin. Her.
But that just goes back to the question of identity and where it lies. If you grew a body with no brain, would it have an identity? I would say not. If you grew a brain with no body, would it have an identity? Maybe?
Yep! That's the whole point of this post, after all. :)
Of course it would. And if you put that brain into a body, the brain would retain its identity.
What if you grew a body without a brain? Would that have an identity? Under our current legal and philosophical systems, it would. If a baby was born without the ability to think, it would still be, given a name, issued with a birth certificate, and treated as a person with rights.
So, we have a situation where we attach identity both to brains and to bodies. If Millie's mind is in Bonnie's body, Millie/Bonnie ("Minnie"?) can use Bonnie's ID to withdraw Bonnie's money from Bonnie's bank account. And, seeing as the post-transplant woman "owns" Bonnie's body, she's not really an imposter. Bonnie's fingerprints are her fingerprints. Bonnie's face is her face.
Ha. What if your twins swapped bodies?
"The Star Trek DS9 episode 'Dax', by Peter Allan Fields and D.C. Fontana"
You might like the VOY episode 'Tuvix' or the later DS9 episode 'Facets'.
I've watched the whole of DS9 multiple times, and I'm working my way through VOY sequentially and completely for the first time right now (but I already know the premise and outcome of 'Tuvix' - I do moderate a subreddit for Star Trek discussion!).