If our “self” is the sum of our parts, why do we feel continuity?

Question

An introduction

I've been feeling a very strong "death anxiety" for at least a week now. It's been really affecting my output, and - even though I understand it's irrational (maybe?) - I can't avoid slipping into this topic anytime I'm thinking about literally anything.

Here's what I've managed to take out of all of this thinking.

If our parts change, can our "self" be the sum of them?

We all feel this sense of continuity, the feeling that the individual that has been looking through your eyes hasn't changed since we were able to remember, but what's the driver that controls this feeling?

If the experience of consciousness (or "self") is an emergent property of everything we are, what's the process that avoids constant continuity "death"? It would make sense that adding ourselves up to obtain a consciousness cake would produce a different cake every time, since we are changing all the time, physically and psychologically

We know our brains and cells physically evolve over our lifetime: They duplicate and regenerate until they cannot anymore, and we start to experience aging. In fact, every 80 to 100 days, a "new you" is effectively present, because every single cell in our body has been replenished. That's a whopping 30 trillion cells on average.

Given the above, how is it that the conscious individual that existed from the exact moment of conception hasn't immediately effectively "disappeared" one single unit of time after the fact? How can we possibly imagine that the feeling of continuity is tied to a physical process?

The nature of this feeling we experience (without fear of it ever finishing, excluding death) boggles my mind and makes me wonder: Could there be a part of our body - physical, let's say, since that's what we know - that deliberately stays static in order to preserve "us"? If so, why? How would that be advantageous from an evolutionary standpoint?

Additionally, how does that part of our body accomplish this static nature? No cell replication, no changes caused by external factors, absolutely nothing.

My reasoning for this is the following:

If you enter to an ER for a brain operation - cancer, let's say - and the doctors interfere with a part of your brain that causes "you" (the individual that entered the ER), to die, what would exactly be the difference? And does this thought experiment even make sense?

The person who continues with their life certainly "feels" like he's the person who entered the operation, their behavior won't change, why the effort to keep the original?

Or maybe the nature of this feeling of continuity is an emergent property of our ability to store and hold memories? But we all know how unreliable memories are, they also change all the time! And what about amnesia or Alzheimer's? Do people who suffer from these horrible diseases lose their "self"? Or do they continuously create new ones?

This thought experiment makes me believe that there's a chance that this feeling is not administered by a physical operation, and rather something external that we may not be able to measure.

Alternatively, memories might just be the key. Maybe some crucial memories are specially preserved in a priority state in order to provide this feeling, but then we jump back into the previous argument, what's the advantage? May this be evolutionary chance?

Or maybe the combined processes of our brains just produce this feeling - and grant it - by identifying the borders of the absence of entropy we produce. But where's the line between lifeless rock and living human, then? Seems arbitrary, and things in the universe don't seem to be very arbitrary at the high level.

Your thoughts? Writing this certainly gave me peace of mind, I hope some of you can try to apply your own logic to this.

Answer 1

There's definitely someone more qualified to explain this than me. But here's my two cents. Take it with a grain of salt.

Sounds like you're talking about being Ship-of-Theseused. The Ship of Theseus is a thought experiment about a ship having its parts replaced. Suppose you replace one board on the deck. Is it still the Ship of Theseus? What about a hundred boards? Now, suppose that after hundreds of years every single part of the ship has had to be replaced at least once. There is no original material left. Is it still the Ship of Theseus?

However, I think that a human differs significantly from an imaginary ship. There are many definitions to what constitutes humanity, and it isn't the body staying the same. Changing (physically and mentally) is just part of living. By some age every cell in your body will not be the same as when you were born, but you are still you.

So, what makes you you is ultimately the combined aspect of memories, experiences, etc. that you've had. But these things are fluid; the mind isn't the best storage medium. You mentioned Alzheimer's and Dementia. I have a relative with Dementia, and she does not remember the vast majority of her life experiences, mostly things from more than forty or fifty years ago, like she's still living in the past. Hell, she doesn't know who I am, and even forgets her son sometimes.

Long story short, identity is fluid. Humans are constantly changing from their experiences. I'd argue that we become a new person every moment. I certainly am not the same as I was five years ago. Not even one year ago. As I see it, you live in a constant present, something that always changes. Don't worry if you were the same or if you'll be the same, because you won't, and that's alright.

Answer 2

Well, we don't really understand consciousness. But it isn't the case that you are the "sum" of your parts, as such. The experience of being you appears to be a product of the brain, yes, but it's also a product of your blood sugar, your microbiome, your endocrine balance, and other factors.

It may be that identity is an emergent property, that is, a property that exists for an entire system that does not exist in any one of the parts.

Answer 3

I would say that the self is neither a physical thing nor just the memories.

I'm inclined to think that the self is all about experience. The self is the psychological entity experiencing things. Every experience changes the self a little, we learn new things, we suffer from bad things, we enjoy good things, we gain memories, good and bad, we form preferences, adjust our attitudes, feel emotions, etc. You could say that the self is the accumulated record of experiences.

Memories are unreliable. We may forget a traumatic experience, but cannot get rid of the change of personality that experience induced.