The Minds Of Conjoined Twins
Conjoined Twins is a biological phenomenon in which identical twins fail to separate in utero and are born and live sharing some or most of their organs. The particular kind of conjoined twins that's relevant to this discussion is the one in which there are two heads and the rest of the body is shared in variable degrees between the two heads that are, in all instances of such occurrences, treated as two different people.
First, the conjoined twins are identical with respect to their DNA. In other words, there's no physical difference between the two. The organ that I'm particularly interested in in this regard is the brain. The brains of conjoined twins can't be said to be perfectly identical; after all DNA doesn't and probably can't code for the 3-dimensional location of each and every brain cell or any other cell in the body. However, if the exact placement of brain cells in space mattered, there should be wide variability in brain function. This hasn't been observed. In fact, despite what are probably extreme variations in the microarchitecture (the exact locations of brain cells in 3-dimensional space) of brains, there's very little variation in its function e.g. all of us sense and respond to the environment in near identical ways. This means that brain function has more to do with gross structure of the brain like the cerebrum, the cerebellum, the amygdala, the corpus callosum, etc. rather than fine structure like the exact location of brain cells. People's brains differ in fine structure and not gross structure and brain function is determined by the latter and not the former is the takeaway here.
As an analogy, take two Toyota cars of the same model. If the exact location of the atoms and molecules mattered to how they perform then we should see extreme variability in their performance, as much variability as there is in the location of particular atoms and molecules of the materials the cars are constructed of. This isn't true, implying that the cars' perfomances are determined by gross structure like the fuel pump, the pistons, etc. and not the fine structure like the 3-dimensional loci of each atom and molecule of the cars' components.
In essence, the two brains of conjoined twins are identical. That takes care of nature.
The conjoined twins that matter here are the ones that haven't been separated for one reason or another. These twins, because they're stuck to each other, share the same experiences - they're exposed to the same ideas and the same physical environment. In short they're nurtured in the exact same way. That takes care of nurture.
Since a person's unique mental identity, personality, is said to be determined by nature and nurture, conjoined twins, because their nature and nurture are identical, should develop identical personalities. This isn't the case, implying that their different minds, personalities, can't be explained by physicalism. Ergo, the mind isn't physical.
First, the conjoined twins are identical with respect to their DNA. In other words, there's no physical difference between the two. The organ that I'm particularly interested in in this regard is the brain. The brains of conjoined twins can't be said to be perfectly identical; after all DNA doesn't and probably can't code for the 3-dimensional location of each and every brain cell or any other cell in the body. However, if the exact placement of brain cells in space mattered, there should be wide variability in brain function. This hasn't been observed. In fact, despite what are probably extreme variations in the microarchitecture (the exact locations of brain cells in 3-dimensional space) of brains, there's very little variation in its function e.g. all of us sense and respond to the environment in near identical ways. This means that brain function has more to do with gross structure of the brain like the cerebrum, the cerebellum, the amygdala, the corpus callosum, etc. rather than fine structure like the exact location of brain cells. People's brains differ in fine structure and not gross structure and brain function is determined by the latter and not the former is the takeaway here.
As an analogy, take two Toyota cars of the same model. If the exact location of the atoms and molecules mattered to how they perform then we should see extreme variability in their performance, as much variability as there is in the location of particular atoms and molecules of the materials the cars are constructed of. This isn't true, implying that the cars' perfomances are determined by gross structure like the fuel pump, the pistons, etc. and not the fine structure like the 3-dimensional loci of each atom and molecule of the cars' components.
In essence, the two brains of conjoined twins are identical. That takes care of nature.
The conjoined twins that matter here are the ones that haven't been separated for one reason or another. These twins, because they're stuck to each other, share the same experiences - they're exposed to the same ideas and the same physical environment. In short they're nurtured in the exact same way. That takes care of nurture.
Since a person's unique mental identity, personality, is said to be determined by nature and nurture, conjoined twins, because their nature and nurture are identical, should develop identical personalities. This isn't the case, implying that their different minds, personalities, can't be explained by physicalism. Ergo, the mind isn't physical.
Comments (48)
Not really. Some favor the left side of their body, others favor the right side of their body. Also, perhaps one has a tiny defect or something. The responsible party is likely to treat one differently over the other, whether for better out of sympathy or worse out of.. who knows what. Maybe the responsible party is either biologically detrimented (poor hearing) or socially disciplined (stricter parent happened to be sitting on one side of the table) to respond differently depending on what side of the head the person hears what from more strongly.
There's an infinite list of scenarios where one twin on one side has slightly different experiences than the other.
If determinism were false, conjoined twins could diverge even if all their experiences were EXACTLY the same, without undermining physicalism. And even if determinism is true, because the experiences of the two brains are ever so slightly different, and brains are chaotic, we would still expect divergent behavior between them anyway.
In the medium term, at least. We would still expect convergent long-term trends between conjoined twin just like we expect between ordinary twins, ordinary siblings, or just people living similar lives, for the same reason that we can predict climate more accurately than weather.
What's relevant to any physicalist notion of mind is the function of the microarchitecture, the numbers and strengths of synapses and how that impacts information processing. You are completely side-stepping this in your discussion which I am unsure why.
Quoting Pfhorrest
How do you know this?
Quoting Pfhorrest
To both of you
Granted that there'll be differences, very tiny differences in my humble opinion, between the experiences of each conjoined twin but what's striking, if we must now discuss degrees and not type in re to the experiences of conjoined twins, is the, what seems to me physically inexplicable, relatively enormous dissimilarities in personalities of such twins.
If the brain's fine structure determines brain function, we should observe a proportionate variability in the way brains operate. This isn't true.
Snowball effect. They can be tiny yet turn into something huge. Say they play a game or challenge where there are two choices, say right or left. One chooses one, the other chooses the other. One is seen as the winner, the other a fool. Or wrong, at least. Again, that could snowball.
Nope. In the previous lines you argued they aren't, that they differ in their 'fine structure'.
Quoting TheMadFool
I imagine that if I had to share limbs with my brother, we would have fought even more than we did. There's a competitive element in people's relations, which has to be taken into account. Some twins want to differentiate themselves from their brother/sister.
I'm not sure if you're questioning the "physical systems" part or the "chaotic" part. I'll admit that I'm not absolutely certain on the "chaotic" part, but given the ridiculous complexity of brains, that seems a safe bet.
Quoting Outlander
This is basically what "chaotic" means: prone to the snowball effect, or more usually, the butterfly effect. Tiny differences at one time amplify to enormous differences at later times.
Theoretically their consciousness should be composed of DNA, experience, and point in space, so you wouldn't think there would be much difference. Suppose their names were Jack and Joe.
Jack would have the experience of living next to Joe, whilst Joe would have the experience of living next to Jack.
Its probably not the same experience, and they would probably want to differentiate.
There are two things to consider here:
1. The brains of conjoined twins are identical in gross structure in the sense both have cerebrums, cerebellums, amygdalas, corpus callosums, etc. As I explained in the OP, brain function isn't determined by fine structure like the positions of the neurons or the number of synapses. If it were there should be extreme variations in mental ability which hasn't been observed. Ergo, it must be that not only conjoined twins but all of us have physically identical brains insofar as function - thoughts - matters.
2. Conjoined twins share the same universe in terms of ideas and the physical environment.
Yet, conjoined twins have very different minds. different personalities.
Were it true that the brain experiences something like the snowball effect, there should be easily observable differences in the minds of different people. Au contraire, there are more similarities between minds of different people than there are dissimilarities. Explain that.
Quoting Olivier5
I also explained that the differences are irrelevant to brain function.
Quoting Olivier5
Exactly my point. Physicalism can't explain this. Kindly read my reply to Outlander.
Quoting Pfhorrest
I think not. The brain is, if you recall your high school biology, the organ that coordinates all the other organs - far removed from a chaotic system.
Honestly I'd consider a bet where if anyone who reads this or ever will who has actually met/known/or seen a conjoined twin in person wins/loses $100. For each. It's beyond rare. That's not really a standard for assumption.
Quoting TheMadFool
How is that different from siblings in strict, if not unrealistic (yet plausible) environments?
Quoting TheMadFool
I'm confused here. There is no observable experience or phenomenon in human existence that doesn't involve.. the human brain. I mean. It's not some non-existent term I made up based on nothing.
Quoting TheMadFool
It's not that bizarre really. Say a few people share a dorm room with the same computer ie. operating system. It's the same base when opened fresh out of the box. Yet, through time, each becomes customized based on the preferences of the individual.
I am sympathetic to the broad thrust of your argument but find this particular premise a bit shaky.
One could posit that the brains of two identical twins are more similar to one another than, say, the brains of two siblings or those of two people taken at random. I don't know whether it's a proven fact but it can reasonably be argued. But brains of identical twins are always different in their 'fine structure' of neuron connections as you say, and the brains of any two strangers (e.g. yours and mine) are generally indentical in terms of their 'large structures' (cerebrum etc.). So the 'large structure' argument works for any pair of brains, not just for twins. It doesn't really cut it here, it's not specific to any twins.
I would rather start with two hypothetically identical brains in the twins. That is, erase the irreducible 'fine structure' differences by making the whole thing a thought experiment: let's assume for the sake of the argument that the twins' brains are identical, so they share the same brain and the same environment.
In this manner one can introduce the inevitable competition between the two brothers (even though they share that competition too) as one of the possible factors of divergence in the twins' general character and attitude to life.
All I can say as of this moment is that it's more than just a hunch. If the fine structure of the brain - the exact number, location, synaptic connections, of nuerons - mattered to how our brain functions there should be pro-rata variations in minds, minds being equated to brain function in physicalism. In fact, generic brain abilities like walking, grasping, talking, thinking, etc. would be impossible if they depended on the brain's fine structure and not on its gross structure which is identical not only for conjoined twins but for everybody.
Quoting Outlander
No different I must admit but so what? I chose conjoined twins to make my case because they're the closest we can get to two brains being physically identical and having similar experiences which, according to the physicalism and nature-nurture theory, should've caused conjoined twins to have similar, if not identical, minds.
Quoting Outlander
Read above.
Quoting Outlander
Ok but customizing a computer can't be explained in terms of hardware. The mind taking on different characters can't be explained by changes in the brain.
Quoting Olivier5
That works in my favor. I chose conjoined twins for the reasons that
1) if two brains can be said to be physically identical then it doesn't get more identical than conjoined twins
and
2) I needed to control for variations in experience (nurture) like exposure to different ideas and physical environments
I think you’re still not understanding the technical meaning of “chaos” being employed here:
https://en.wikipedia.org/wiki/Chaos_theory
A lot of that high school stuff is now very dated. When an organ is transplanted, the nerve supply can not be rejoined, but the organ nevertheless is able to function. So it can not be said that the brain is controlling it. The organ seems to know what to do and how.
Quoting TheMadFool
I was very excited by your post, as what you posit would be a way to prove bodily feeling experienced by one is also felt by the other, but reliable information is scant. I can only find unreliable information.
The twins are conjoined in various different ways, and this results in various different outcomes. There are just not enough of them to come to any conclusions, I feel.
I understand chaos as the behavior of a system extremely sensitive to tiny differences in initial states.
My problem with this is whether chaos theory is applicable at all to brains? There are two forces acting on the brain, 1. ideas and 2. the physical environment.
I can accept that the physical environment (temperature, humidity, air pressure, etc.) can vary quantitatively in ways that chaos in brains becomes possible a la the classic butterfly effect. However, if the physical environment has such an effect on the mind, we should be seeing a clear gradation in mind-types (gradation in beliefs, attitudes, etc.) with latitude, temperature being the most well-defined variable in physical environment. What I'm saying is the minds of people living in hot places should be different from the minds of people living in cold places. I haven't come across any scientific study that makes such a claim. Perhaps something worth investigating.
Coming to ideas, the notion of small differences in initial states doesn't make sense because ideas aren't quantifiable like temperature or humidity or air pressure. It's nonsensical to say that one person was exposed to 1.002 of atheism and another person to 1.012 of atheism.
All in all, chaos theory doesn't seem applicable to mind and its environment.
Quoting Pop
Organ coordination is done not just through nerves. Hormones which trace their origins back to the brain are another control mechanism.
You seem to be thinking of the brain as though it were a gas, with its processes predictably correlating with the things that you list (temperature, humidity, air pressure, etc). That has nothing to do with chaotic things like the butterfly effect; in fact such a correlation is contrary to them. The brain as a chaotic system would be one in which, say, a single sodium ion either does or does not make contact with a neuron because of some small physical difference, and then that neuron does or does not fire in accordance with that, and then all of the neurons that would fire in response to that one firing either do or do not fire in accordance with that, and then all the neurons that they would trigger to fire either do or do not in accordance with that, and pretty soon you've got a vastly different state of which neurons are firing, and so what the brain overall is doing, all because some trivial physical effect either did or didn't inhibit the motion of a single sodium ion.
This still doesn't make sense. You mean to say that if someone were to introduce me to atheism/theism, my response to it depends on variations in sodium ion concentration and sodium channel activation. If this were true there should be more shades of these ideas then there actually are; after all at the molecular level of neurochemistry variations are continuous and exist over a wide range of concentrations and activations of sodium ions and ion channels. Basically, the limited output - variations in theism/atheism - doesn't square with the enormous input - variations at molecular levels.
Probably not in that direct a fashion. But your response to the ideas of atheism or theism would depend heavily on your other life experiences, which would depend on previous life experiences, where those life experiences can be influenced tremendously by tiny choices you make, tiny variations in your mood, things that aren't such a clear black or white conscious choice but more something that you wouldn't be able to clearly state why you did one thing instead of another, you just felt like one more than the other; but those choices ended up giving you a different experience in your life, and that different experience in your life changed how you would react to the ideas of theism and atheism. And those tiny subconscious states of mind that can send you down one life path instead of another can be influenced by small changes in neurochemistry.
Fair enough but it's still a mind experiment, so there is no harm in assuming the two brains absolutely identical in every way at start.
You mean to say that beliefs are dependent on one's mood. This turns philosophy on its head. Can you elaborate on this point.
Please explain specifically what you mean by function and operate. Like I said, if you mean generalized function of a specific brain tissue like olfactory bulb, amygdala or visual cortex, then this is just a strawman because these things are not relevant-- i.e. it would be like saying the hard disk of computer A functions the same as computer B [i.e. they store memory], thus
the variability of the microstructure [i.e. the orientation of magnets on the hard disk, which is the physical representation of the computer memory] doesn't matter for what the hard disk does. But it does matter.
If by function, you mean the specific output of a person's brain tissue, then the function does vary considerably. The output of your visual cortex when viewing a tasty, gushing burger is completely different to the output of my visual cortex when viewing a chair. The output of my amygdala after seeing a picture of Natalie Portman is not the same as the output of my amygdala after discovering a spider crawling up my arm. And those outputs are different in other people.
Not directly. But they're dependent on previous beliefs, which are dependent on previous experiences, which are dependent on previous choices, which are dependent on previous moods. It's not as simple as you want to make it out, so as to easily refute it.
Quoting Olivier5
Long-term climate trends are also highly predictable and regular, but weather is very chaotic. I mentioned this comparison in my first post in this thread.
I believe that consciousness is one such mechanism working toward coherence. It's an integrative mechanism, like a mental dashboard, that prepares for action. Action is singular by nature:you can't flee and fight at the same time, you can't make two chess moves at the same time. You must chose one way or the other (exclusive 'or') often under severe time constraints.
Such integration of disparate information and thoughts into a coherent framework for data-based decision making must be an energy-hungry and tiring process, which would explain sleep as a universal phenomenon among superior animals. Sleep is when our mind disintegrates a bit.
In this view, schizophrenia would be a mental integration failure.
Take your brain and mine for comparison. It's quite obvious that they differ in terms of actual number of neurons, the number and complexity of synapses, the loci of brain cells, etc. Yet, we can both talk, walk, eat, think in, factoring these variations, extremely similar ways. Had these variations any effect on the way our brains operate/function, it would show in the areas of brain function I mentioned. We wouldn't have generic abilities like walking, talking, eating, thinking, etc.
Quoting aporiap
You're comparing apples to oranges. Of course our mental states would differ between a delicious burger and a spider crawling up our arm. However, if both of us were exposed to the same stimulus, we would experience comparable mental states. If my mouth waters in gustatory anticipation when I see a burger, it's highly unlikely that you would retch and vomit in disgust. This similarity in responses to the physical environment and ideas bespeak the reality of what I've referred to as generic brain functions, something that would be impossible if the fine structure of brains mattered to mental states.
Quoting Pfhorrest
So, is it fair to say that the belief your espousing in this thread is ultimately mood-based? Why are you trying to argue then?
Moods are just an example of a subtle non-rational brain process that can go on to influence your life in the future. They’re not at all integral to the point I’m making.
For another example, say you’re on a walk one day and at a fork in the road you have to go left or right, without any real reason for either. One of those choices will lead you to meet a person who will become a short-time acquaintance of yours through whom you will meet someone else who will introduce you to a new circle of friends among whom you will meet your future spouse with whom you will have many deep conversations that will heavily influence your opinions on things like theism or atheism. If you turned the other way on that walk, your future state of mind would have turned out completely differently. And whether you felt inclined to turn left or right is the kind of thing that could be influenced by tiny physical differences, or more likely built up to by an accumulation of consequences of tiny physical differences in the same way that your future beliefs were built up to by an accumulation of differences based on whether you turned left or right.
You lost me. I'm under the impression that you're talking about moods to prove that beliefs depend on them in a very important way, to wit that they're the tiny, almost imperceptible, differences that are part of your chaos theory of mind.
Quoting Pfhorrest
I understand the significance of differences in experience for how we turn out to be down the road but conjoined twins don't have that luxury. They're stuck to each other, remember?
Yeah, the left-or-right thing isn’t meant to apply to the twins, it’s just a clearer example of the butterfly effect. A tiny insignificance change can snowball into a large difference through unpredictable complications. Likewise, tiny differences in the two twins’ brains compound over time into larger different between their brain-states. We would still expect a lot of similarities of their brain states, because of their shared experience and genetics, but this allows for enough differences to explaining why they aren’t exactly the same person despite those similarities.
I don't see why microstructure needs to impact the function in the way you describe. It's like the example I gave of the hard disk. Two hard disks have the same function despite widely different microstructure, and its the microstructure that matter for what is stored in memory. Another example would be like two animals, a llama and tiger. They have brains with similar parts, visual cortex, amygdalas, etc. What makes them different in behavior is the microstructure. The difference in microstructure doesn't need to imply different functions for it to be important for minds or for determining specific behaviors in specific contexts.
Quoting TheMadFool
Are you implying every part of two different brains, respond in similar ways to a stimulus? But this is clearly false; just read any comparative brain study. Presented with that burger, I could just not have a watering response or I could have a different set of thoughts triggered by that stimulus. Two people don't have similar microstructural, behavioral emotional or cognitive responses to the same events. These are what form the basis for differences in personalities, emotional sensitivity, behaviors etc.
Even simple neural networks are chaotic systems. This has been shown experimentally since the 1980s and is now a well established fact. See here and here. What this means is that very small differences in the initial state of the network will give rise to significant unpredictable differences in the final state. Apart from that, the anatomical and the biochemical arrangement of the nervous system in craniopagus twins are not identical. At the very basic level, their heart rate and blood pressures are not identical, hence their CNS state will not be identical.
Quoting TheMadFool
Even if our way of walking is similar, it is as different between individuals as are fingerprints. Individual gait is different and you can identify a person by his/her gait only. Prosapagnosic patients (who are unable to recognize faces) can readily recognize persons by watching how they walk. It is the same for the way we talk. This shows the opposite of what you are trying to say - gross structures in our brains are the same, hence we walk similarly, but there are differences in the little things, thus each of us has individual gait, out own individual way of talking.
Quoting debd
Do you see people behaving chaotically?
Quoting debd
You're focusing on minor differences and ignoring major similarities. What you're doing here is like taking two humans and concluding that one of them isn't human because fae has a differently shaped nose.
My argument is simple, if the brain is a chaotic system there should be zero similarities between people which is clearly false.
Quoting aporiap
:chin: You're contradicting yourself.
Quoting aporiap
Each gross anatomical structure of the brain has a function that's different from other gross anatomical structures but each one of them has a function that's identical to all brains.
No it isn't. You are not reading it in context of the example, see the sentence preceding the quoted ones. Behavior and function are decoupled in that post, so there is no contradiction. Functions denote activity of a given brain tissue - e.g. amygdala. Behavior denotes things like walking, grabbing, any action. Llamas and tigers have different behaviors despite having the same brain functions [amygdala function, visual cortex function]. How would you explain why they have these different behaviors given the identical functionality of their brain tissues? How are he microarchitectures relevant?
Quoting TheMadFool
Do you distinguish between output and function of a given brain structure? By output I mean the spiking rates of efferent neurons exiting the brain structure.
This is a good point but...
First things first, tigers behave quite differently from llamas. This seems to bespeak a correlation between brain and behavior especially in terms of fine structure: the differences between a llama and a tiger are due to differences in fine structure of their brains. Your theory explains interspecies differences. So far, so good.
However, how would you explain interspecies similarities? I mean both tigers and llamas walk, eat, mate, etc. If it all depended on fine structure of brains, and given that they're not the same in these two species of animals, tigers and llamas should have nothing in common and yet they do in the aforementioned ways.
Chaotic systems are mathematically defined systems, it does not mean people will behave chaotically. You are confusing chaotic systems with the common use of the word chaos.
Gross brain structures are similar across individuals of a species -> that's what makes them a member of the same species. However, there are demonstrable differences between the gross and microscopic structure, physiology and biochemistry between individuals, that is what separates you from me. Gross brain structure allows us both to speak but its the differences that make your speech utterly unique and different from mine.
I don't mean to be rude but you're trying to eat the cake and have it too. Firstly, you and some others are trying to explain differences between individuals, whether belonging to the same species or not, with chaos theory. Clearly, in such a theory, the input are the differences in environment, minute ones as per chaos theory, that's causing large variations in output. Put simply, the chaos is in the output - the mental and bodily aspects of a person. In other words, you're saying these very differences - mental and physical - are the chaos. Then you go on to deny this is so. :chin:.
However, what explains the similarities then? If chaos theory is applicable to brain-mind there should be absolutely zero similarities between individuals, same species or not. Yet, animals share a sizeable chunk of their biology with other animals.
Quoting TheMadFool
It is not a question of if, experiments have shown that neural networks exhibit chaotic dynamics. However, this does not mean it cannot be analyzed or predictions cannot be made.
Weather and climate again.
It’s very hard to tell exactly what the weather will be like on a particular day even one month away, but I can guarantee you there will be no rain in my hometown on any day in July ten years from now.
Quoting debd
In keeping with your theory, the chaos manifests at the level of behavior (mental AND physical) but there are similarities at those levels which should be impossible (in your chaos theory).
Quoting Pfhorrest
You mean to say you can predict the climate and not the weather? Any references to support your claim? Also, kindly explain the analogy in more detail. What aspect of our minds is the climate and what aspect of our mind is weather?
Some top Google results:
https://www.nasa.gov/mission_pages/noaa-n/climate/climate_weather.html
https://www.ncei.noaa.gov/news/weather-vs-climate
Quoting TheMadFool
Someone else already gave a great illustration with regards to a hard drive earlier. The magnetization of individual bits on a hard drive can be completely different, but the whole structure of the hard drive remains that of a hard drive. The magnetization of individual bits can change drastically and unpredictably over time, like weather, but still the general overall structure of the drive remains the same, or only changes very slowly, like climate.
So I can't know what the microstructure of my hard drive will be like tomorrow, what with all the many crazy processes always changing that; but I can be pretty sure it will still be a hard drive a year from now. Likewise, I don't know for sure it won't rain here tomorrow -- this is the time of year when it starts to rain around here, but exactly when the first rain will be is hard to predict -- but I can be virtually certain that it will not rain at all next July, or the July after that, etc, because raining in July is just not something that can happen here.
And likewise, brains have a general structure to them that is going to be the same no matter what, barring traumatic injuries. But the microscopic brain states can change radically and unpredictably, and with them the mental states that they encode. Yet there are limits on the kinds of mental states that be had too -- you can scarcely more be "a little bit theist" than you can be "a little bit pregnant" -- so all those variations on brain microstates just influence how likely you are to end up in one of the fewer possible mental states, in such cases.
This analogy doesn't work for the simple reason that it doesn't include a functional aspect. The brain is the hard drive, ok. However, the brain has a function which is expressed in the form of thoughts and behavior. The analogy of the hard drive doesn't have a corresponding attribute. If we do attempt to complete the analogy, the content of the hard drive should stand for brain function but any changes in the fine structure of the hard drive will produce a corresponding change in the contents of the hard drive.
The content of the hard drives is analogous to mental content — your thoughts, beliefs, feelings, etc. That stuff can and does change, which is the whole point here, accounting for origins of that change. The overall function of the brain though, like the overall function of the hard drive,
remains the same; those big features are relatively fixed and not easily altered.
Ok, the contents of the hard drive are mental content. Changes in the fine structure of the hard drive alters the contents of the hard drive just like differences in the fine structure of the brain alters the mental content. What, in all of this is the "overall function of the brain" that has remained "relatively fixed"? If I alter one single bit on the hard drive, the content will change dramatically - this is the chaos you're referring to. I fail to see what has remained "relatively fixed"? Remember we're not discussing the function of the hard drive as a memory device. You were so kind to point out that "the contents of the hard drives is analogous to mental content - your thoughts, beliefs, feelings, etc."
My issue with your theory of "chaotic dynamics" in re the brain is very simple. Your chaotic brain idea explains the differences. In fact it's express purpose is to demonstrate how two brains, despite being exposed to the same enviroment in a broad sense, will diverge in mental qualities such as beliefs, attitudes, desires, likes and dislikes, etc. for the reason that brains are sensitive to tiny differences in the environment. In essence, your theory is meant to explain differences between individuals. How can you use a theory that's primary objective is to account for differences as a explanatory basis for similarities? It's like using using Darwin's theory to explain Creation science. It makes zero sense [to me].
That’s another good analogy.
There are a lot of mutations that are possible, caused by tiny random environmental factors, but most mutations either do nothing of note, or cause the mutated cell to die. If they don’t, the mutated cells usually malfunction and get killed off by other cells. It’s a very rare mutation that produces a lasting genetic difference... and most of those make no noticeable phenotypic difference. Those that do, again, are usually detrimental to the organism, and are quickly weeded out of the gene pool. So out of all the chaotic mutations that could happen, there is a very limited selection of phenotypic changes that can be introduced into the population; it’s not like a stray cosmic ray can just cause a horse to give birth to a pegasus.