>>> The person you are today doesn’t share a single cell with the version of you from seven years ago. (This is, of course, a generalization as some cells regenerate much faster and others a little slower.)
No, that is not even remotely true. Most of the neurons in the central nervous system (the part of the body one could argue does the most of thinking) stay mostly the same from adulthood to death[1].
I once heard that this is an oft repeated myth, that neurons are not replaced throughout life.
It seems to me to that what you said is true, but for some odd reason I have a recollection of reading a debunking of this. Does anyone know what I might be thinking of?
At the moment, the consensus seems to be that some neurons[*] are occasionally born in adulthood (e.g., in the hippocampus), but there’s a lot less agreement on why or if this matters at all. It could be the remnants of a prenatal process or a neat method for providing “pointers” into memories.
* In the brain itself. It is widely agreed that olfactory sensory neurons turn over every month or two, but they almost have to because they’re exposed to all sorts of junk in the air and wouldn’t survive a lot longer anyway.
Consciousness is the only thing that can not possibly be an illusion.
Whenever this comes up I have to wonder if half the people are secretly p-zombies and actually genuinely aren't sure whether consciousness is an illusion because they've never experienced it? I know that's not a very charitable take but I just can't see how any conscious being could imagine that consciousness could be an illusion!
Consciousness isn't the illusion, consciousness is the audience!
Begs the question: by what metric are you using to track the change/staticity?
I don’t see how one can concretely come to the conclusion of whether it changes or stays the same, when the presence of consciousness itself is a prerequisite of making that very claim
The me who is engrossed in a conversation with a peer over dinner at night focusing on the topic at hand surely is a different consciousness as the me fighting to stay awake just after lunch. They think and emotionally experience very different things.
Well if you believe there's something magical about consciousness I could see why you'd believe the same person's consciousness at different points in time is the same consciousness.
If you believe consciousness is a function of sentience and self-awareness, and presumably that AI can one day be conscious (not saying it is right now), then I don't see how you can believe consciousness is persistent.
If the AI is copied/moved to a different server, is it the same consciousness? Or in Star Trek when you get beamed up are you the same consciousness?
Safe to say you tend to lean towards your second presentation of consciousness.
I tend to lean towards the idea that conscious is akin to a field in the sense of an electron field - that what we can measure are simply “excitations” of a more subtle field. Not a perfect metaphor, but it’s the closest thing to what matches my meditative experiences. IMO, it’s illogical for me to let another subjective being define what my substrate is, so I primarily rely on meditation and then supplement with objective observations.
All in all it really depends on what you define as consciousness. The issue that I have with most “objective” interpretations of consciousness is that we can only measure the excitations of this mysterious “life” thing is. If there is more to us than can be measured, e.g, that there are first person experiences that can be felt subjectively but not measured objectively, then any objective measure of consciousness will likely be limited. Consciousness seems from my pov to be the Achilles heal of the axiomatic assumptions of our scientific paradigm (at least in the west)
In response to your question, it depends on your definition of consciousness. Is neural activity the source of consciousness, or is neural activity the result of consciousness? How can we know for sure which?
I agree. It has a great parallel to the debate over mental imagery. There was a big debate over whether it’s real, with one group saying of course it’s real, and the other saying it’s obviously just a metaphor. Turns out some people can visualize stuff and some can’t. Maybe some people are conscious and some aren’t. It would explain why so many people argue weird things about consciousness.
> Consciousness is the only thing that can not possibly be an illusion.
It can be. Suppose consciousness is a series of infinitesimal snapshots, where existence flickers for a moment and then disappears, with a new existence birthed in the next moment. Like a motion picture, at each moment we do not have a sensible version of consciousness, merely a burst of sensation, but in aggregate, as a film, consciousness springs from nothing.
That's just an implementation detail, in aggregate the result is still consciousness. It's like saying animation isn't real because it's just a sequence of still images.
I'm not arguing that consciousness is and illusion. I'm only arguing that it is possible that it could be an illusion. It's probably not, and if it were, it wouldn't matter. I'm just saying it's possible.
But it doesn't. Because the film depends on the screen and the projector. This was one of Kant's central points, although he used the fancy term "transcendental unity of apperception". To even experience a set of images as disjointed, to see individual parts as relating to each other there has to be a unified experience judging them as disjointed against, the "thinking I". Without the observer already implicit in the thought experiment about images constituting a film, there is no "film" because nothing in it would have the ability to even conceive of itself as such. Hindus have a very elegant term for this "witness-consciousness" (Atman), importantly like in Kant distinct from ego and mind, not experience but a formal condition for experience. David Bentley Hart also has a great section about this in his recent book:
"Every composite thing, he acknowledges, is an aggregate of several other things, and all its actions are aggregations of diverse actions and accident. [...] If it’s the composite thing that’s doing the thinking, then each part of the composite possesses only a part of the thought, and only in the aggregate is there a complete thought—but then who or what is having that thought? Where does that thought as a unity occur? Can it be just another part of the brain, with its own diverse parts and its own necessary inner coordinating facility? But then that too is made up of partially competent ..."
Ultimately it doesn’t matter if it’s reasonable. If it were true, life would be absurd. So, philosophically, we can assume it’s untrue because the alternative means being wrong about it doesn’t matter.
People run on autopilot unless we put in effort to focus on the current moment. Almost everyone demonstrates bad habits that show how little conscious awareness and control we have. LLM’s can replicate a lot of our activities, so the realm of “consciousness” is in the things that the AI can’t do by simply repackaging and regurgitating content back at us. What we can claim as conscious special sauce has grown smaller over the last 15 years.
Argument 2:
Could we design a machine that is absolutely sure it’s conscious, but is not? If so, what differentiates us from it? Open question, I’m not sure. But I’d be surprised if we can be permanently sure.
Argument 2 seems more like a thought-experiment or a question than an argument. (Unless maybe I missed the point?)
Anyway, isn’t a machine that “is absolutely sure” (of anything at all) having subjective experience (I think is the word, not a brainologist) by definition anyway?
We could clearly design a machine that asserts that it is self aware very strenuously
printf(“I *am* experiencing existence!”);
But whether or not it actually sure of anything or experiencing at all is the question in the first place.
How do you know you’re not an automaton that thinks it’s conscious?
Not feel. Not think. Not have a strong vibe. Proof.
I don’t have to prove anything here, because I’m not the one making an assertion. My thought experiment demonstrates a situation where an entity thinks it’s conscious but isn’t. Humans think we’re conscious but can’t prove it.
I think we’ve skipped defining terms, which makes it hard to work out exactly what your thought experiment is trying to say.
What does it mean to be conscious? I (layman, this is a well-explored space so maybe somebody more informed will come along with a better definition) would define a conscious being as one which has subjective experiences, that is, one which has has the sensation of thinking. Therefore I know I am a conscious being by definition.
I mean this is just “I think, therefore I am.”
It is definitely possible that I’m an artificial being programmed to have first person subjective experience. I can confirm, if so, to my creators that their experiment was successful. But, I can’t offer any proof, and of course they would be totally reasonable to assume I am lying.
In your thought experiment, you say an entity that thinks it is conscious, but isn’t. By my definition of consciousness, that is impossible, because thinking things is definitionally a characteristic of conscious beings. It is fine if you want to use a different definition of consciousness or thinking, I just assumed and later supplied (my bad, I also should have defined in the beginning) what I thought were typical definitions.
This is exactly the kind of thing I was talking about.
How can you be remotely unsure about whether you are conscious? It is inconceivable to me that you could be conscious and unaware of it. It's an oxymoron.
Of course you can be unsure about whether others are conscious. But if you are conscious then you know that you are.
Do you experience things at all? Or are you a soulless machine that takes inputs and gives outputs and doesn't experience anything on the inside?
We “experience” consciousness in the same way we experience hard objects that are actually made of mostly space. It feels right but it’s impossible to say that it’s the truth.
There are a lot of smart people who are less sure that our perceptions reflect reality. Free will, time, consciousness, space all feel very real. But when you interrogate them enough, those fall away. Go fast enough and your time slows down. Go as fast as a photon and time and distance disappear entirely. Yet we’re sure they’re real. At one point we absolutely knew the sun revolved around us. We could see it doing that daily.
One smart person on free will below. There are so many others. There’s certainly no consensus that “our experience = how things are”.
The point is that our perception doesn’t provably equal “truth”. To make absolute statements you need to be a lot more sure and be more correct than all the smart people who say “not sure yet”.
> The point is that our perception doesn’t provably equal “truth”.
That's fine, but that you have experiences at all proves that you have experiences.
I'm not saying nothing can be an illusion! I'm saying that consciousness specifically can't be an illusion, because if it was an illusion you wouldn't be experiencing anything at all.
You mentioned smart people and I wondered who you were talking about. Then you said Sam Harris who has a reputation for being a clueless idiot in philosophy circles.
Most philosophers are compatibilists, since that’s a good strong philosophical position. Harris is just saying libertarian free will doesn’t exist, but that’s irrelevant since that’s not what people really mean by the term.
Consciousness is a phenomenon, but not an illusion. An illusion is something that seems to be there, yet is not. But consciousness is a self-evident experience.
However, there are gradiations of consciousness. The experience we have on the edge of sleep is qualitatively different than the experience even five seconds after waking up to a cat attack in the middle of the night (I have experienced that).
You’ve stated this so matter of factly that I imagine you have knowledge that somehow has alluded most people.
You mention gradients, which implies you can measure the delta/change of conscious, which implies you have a solid working definition, AND a static still point that does not change which this “consciousness” gradually changes.
From my perspective, which is first person pov, if I can detect changes in my “consciousness”, then where am I looking from to _notice_ this change? Is consciousness not the requirement of change detection?
I thought so too, but it seems reasonable considering we're 70% water, much of it flowing and actively taking stuff out and around. Plus cells are apparently way more dynamic than is typically conveyed in high school bio (I think there was a quantamagazine article a while ago). So it's perhaps surprising that a body's atoms aren't fully recycled even faster than that.
The Ca in bones is probably renewed very slowly. C H O N very fast, in particular water. Na, K and Cl are very soluble and also get renew very fast. Some rare elements like I are probably reused a lot and renewed very slowly. I'm not sure about P, my hand waving is confused. Assuming a burger per day, we ate our weight in meat every few years, but I'm not sure if all the Fe is absorved in and exchanged for the internal one.
Without resorting to metaphysics, “I” am a slowly-but-constantly changing set of experiences, memories, predilections and preferences that happens to be instantiated in and associated with a particular physical body. My relationships with other people tend to be the most important things to me and the things that most shape whatever direction my identity is going.
My body is not the same exact set of cells or molecules that I was 30 years ago. But I’m like the Ship of Theseus- the essence of what I am is a direct consequence of my formative experiences regardless of what pieces I’m built of at any given moment.
It’s my choice (within the constraints of how brains work) of how much I let past experiences affect my current behavior. But I can’t forget those experiences and if I could, then I would not be the same “me” in a much deeper sense than just having different cells or molecules.
> I recently spoke with a friend who was still dwelling on something that happened thirty years ago. “Why do you care?” I asked him. “That was four versions of you ago. That person doesn’t exist anymore. Move on.”
Do you think this actually helped your friend? In any way?
Of course! It helped your friend realize what kind of person you are and hopefully spurred them to find better friends who possess actual human empathy.
It feels so strange to read blogposts like this in 2025. The level of mediocrity makes you question if this has been created by a human or an ai bot. Next you start questioning yourself why you still look into your smartphone like a junkie.
So if Theseus was aboard his ship for many years it would add another layer of it that ship still is his own?
In Vernon Vinge’s A Fire Upon The Deep you have pack of dogs that are not so smart individually, but they had a pack personality that was smart. Even (for one case in the book) the dogs could be replaced but the personality remained.
Changing individual cells doesn’t change what is the you of your consciousness and memories. Of course, even without cell replacement you change with time, new memories, insights and so on, but both changes happen at different abstraction levels.
Peter F. Hamilton's Pandora's Star contains a wonderful variant of this thought experiment: in the future he describes, memories are editable; so it's possible to commit a crime, like murder, and then wipe all memory of it, so that you are, from your own perspective, innocent. The justice system, of course, says otherwise. The metaphysics (whether or not it's possible to step into the same river twice) don't matter. Technological advancement dictates the answer to the philosophical question about continuity of the self and guilt.
Depends a lot on the mistake and your life since then. Is it something you could still fix today? Is it a mistake you keep repeating? Is it a huge mistake that still directly impacts your relationships and today in some way?
I think mistake is an overused word, and a choice that qualifies as a mistake in the future may not be judged as a mistake now.
Simply put... we make choices based on the information we have now. And our future judgment of our choices should account for the information we had back then, most of which has probably been forgotten.
But to answer your question, we shouldn't regret our mistakes but it is very good to remember them.
I think the correct answer in terms of mental health is: as little time as possible.
The actual answer is more complicated. Someone who got locked up for 25 years knowingly committing a significant crime might regret it for the majority of their sentence, at least.
I don't think this is true at all. Living your life ignoring all of your past mistakes can be just as unhealthy as dwelling on them needlessly. Dwelling on past mistakes can lead to hopelessness and depression, but ignoring them entirely can lead to narcissism and repeating damaging patterns.
I'm reminded of the SMBC comic https://www.smbc-comics.com/?id=2722 which resonated with me. If it takes ~7 years to master something, you should dedicate yourself to becoming good at it. Or at least you don't have to tie your identity to what you do you right now; you can reinvent yourself and experience more from of life, but you have to give yourself the time to do so.
It's been almost 14 years since that was published, so maybe some self-reflection is due.
It can be emotionally freeing to learn from the mistakes of that other person you used to be, rather than your own mistakes which you return to again and again with feelings of regret.
So basically, it’s a neat mental trick to provide emotional distance and allow you to move on with your life, and also allow you to keep your mental model of yourself fluid (changeable).
Lots of comments here disagreeing with the article and missing the point...sure, the seven-year rule can be taken to a ridiculous extreme, but I think many people suffer from dwelling too much on past mistakes and overcorrecting them. Seven years seems like a roughly reasonable period of time to learn from a serious mistake and then move on with life as an improved person.
The spirit of the article is saying that you should ultimately forgive yourself for making a mistake after a period of time (not always literally seven years).
Thanks for saying something. I’ve noticed other folks on other threads making similar comments to argue against opposition that doesn’t even exist apropos of nothing and it feels like a self-fulfilling straw man building prophecy that they’re willing into existence.
Perhaps it be better to consider 3.5 years as a half-life instead.
Every 42 months, half your life has or could be upturned.
That’s how long it takes to find yourself in new job, or for a new child to become a fully talking toddler with a personality, or a long-term relationship to solidify, or a national government to turn over, or a pandemic to initialize and then resolve. That all tracks.
Nope. I am going to decide not to renew myself into a new thing.
I don't live like Buddha or the Dalai Lama. I don't have a castle or forest of isolation to shed my skin. I also don't want to.
I am shaped more by what others perceive of me than myself. It is a tragedy of this age. I cannot change that.
But I can challenge some of those assumptions by choosing to see things from multiple perspectives. By choosing to not completely do that to others (there's always a risk, but hey, I'm doing the best I can. Are you?).
I have learned to perceive Buddhist thinking in this age as a difficult thing to concilliate with reality.
Religion-like rules are supposed to draw my attention. Well, fuck it. I cannot avoid it, but I can choose to try to understand what it means in this context I am, which, again, is very different from what some Lama wrote.
Sure, I can totally empathize with someone who is tired and wants to let it all go. I have been there. You can let it go, and it's OK with me. But I cannot pretend that I enjoy this Mad Men transition into eastern meditation clear-your-mind shit. Fuck that.
What I am is deeply shaped by living among others, being influenced and shaped by others opinions. I will not forget that. But I can pretend to. Not by their rules though. As I said, can't forget.
This post confusingly conflates "cells" with "self" resulting in a muddled and pseudoscientific message. It reads more like feel-good content than facts and would be better suited for other social media platforms.
"So why not focus your energy and attention on the present moment?"
Because sometimes having a better future requires focusing on that instead of just now. Of course, ironically, having a better future often requires I become more present in the moment I'm in...
> As you read these words, you are uniquely yourself, different from who you were a moment ago and who you’ll become in the next.
By extension, a "culture" is a snapshot of a subset of the human population. To be clear, copious physical artifacts outlive people, so the state of the State is more than my reductionism.
No, that is not even remotely true. Most of the neurons in the central nervous system (the part of the body one could argue does the most of thinking) stay mostly the same from adulthood to death[1].
[1]: https://en.wikipedia.org/wiki/Neurogenesis
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