Difficult to comment on such a phenomenon. Even though our cells are replaced regularly it doesn't necessarily mean that it is in some different configuration, yielding differing memories, values, or genetic blueprint. I think that memories are perhaps our only feature that persists over time to some extent. To what extent is a mystery.

I think that memories are perhaps our only feature that persists over time to some extent. To what extent is a mystery. — Wallows

The extent may even be infinite, considering the existence of history. One may regard history as a collection of memories reaching back to the dawn of humanity.

Do you see any distinction between the issue in the OP and the Ship of Theseus?

Its really a hard problem.

There is one thought experiment out there, that I know of. Teleportation!

If person A exists with an particular and certain atomic configuration for their body and mind, do they remain the same when reconstructed at another point in space-time? Some say it would be the same person, other's claim that they would not be the same.

Really there is only two possibilities here.

I think the provided experiment gets at the consistency of the self, just as the idea of biological consistency does.

If it weren't for memory, would person B be the same person ten years after all their cells and atoms where exchanged?

This has to mean that we have metaphorically categorize our peers in such a way that trancends matter, otherwise we wouldn’t be able to even be a ”consistent” person for more than 10 years post-birth. — Pelle

How does this follow? As long as one looks similar enough to how they did previously it doesn't seem strange that we'd still regard them as being the same person. We easily recognize the causal chain that makes them the same person as before and visually they aren't too different, so we say they're the same person. Cell replacement seems to be completely immaterial here.

Perhaps an interesting excursion from this line of thought is the thought experiment called "Swampman". Anyone know something about it?

Right, almost all of the body cells are replaced periodically. The exception is the brain and the muscles of the heart.

It's not quite settled whether the brain adds brain cells; it may add some, but nothing remotely close to replacement numbers. That's why neurodegenerative diseases like Parkinson's disease are so devastating. Once the substantia nigra cells are destroyed, one has advanced Parkinson's disease for the rest of one's life. Injured brain tissue (tumor, fall, impact) doesn't recover. Other parts of the brain may take over a function, but the injured tissue is not repaired the way a broken bone is repaired. When you have a heart attack, the damaged muscle is replaced by scar tissue, not new muscle.

a way that trancends matter, otherwise we wouldn’t be able to even be a ”consistent” person for more than 10 years post-birth. — Pelle

There is something in the body, some specific matter, that provides guidance for the continual replacement of the skin, bone, blood, lung, liver, etc. cells: DNA. All of the tissue you recreate during your lifetime are constructed according to very specific DNA instructions. Sure enough, over time we change: as we age (say... past 60 years) our spinal structure begins to collapse and we will lose height; the eyeball changes shape, and glasses are required. The cartilage in the joints wears away and we become arthritic. Our hair turns gray (if we are lucky) or it falls out altogether. All of these processes are overseen by the genes.

How about cancer or other diseases affecting the genes? If DNA is the primary predictor of individuality wouldn't that person be biologically changed in such a manner that they're not the same anymore (especially if said mutation/condition has large implications on appearance and/or personality)?

Also epigenetics...

How about cancer or other diseases affecting the genes? If DNA is the primary predictor of individuality wouldn't that person be biologically changed in such a manner that they're not the same anymore (especially if said mutation/condition has large implications on appearance and/or personality)? — Pelle

Were our genes to become very disordered, we would drop dead. Big change, for sure.

On one level we are constantly changing and on another level we are stabile individuals from one year to the next. It is a paradox. Even if all my cells have regenerated 100% I maintain the same identity, cognition and personality characteristics. If I learn something I didn't know before, I might be slightly altered, even though that alteration wasn't the result of new cells. The Lacks cervical cancer cell line has been multiplying rapidly since 1951, yet remains the same; that's why it is a workhorse of cancer research.

I could lose quite a few pounds of corporeal weight and remain the same person. The brain weighs about 3 pounds; an ounce or two of tissue loss there might make me a different person (depending on which ounce disappeared).

POINT IS: I don't want to open the door to an interpretation of mind which isn't solidly anchored in the physical brain. Mind is derived from matter, and experience tells me that despite all the changes going on cell by cell, my self-identity, my perceived identity to others, and my legal identity is quite stable.

Substantial changes in the brain, and an injury or diseased ravaged body may alter me so much that lose my previous identity. But then look at Stephen Hawking: his body was practically gone, but he remained the same insightful thinker long after his body stopped working. (Granted, he required a lot of support to continue functioning so well.)

What would the metaphor be?

Even though our cells are replaced regularly — Wallows

Who's cells are being replaced? @Pelle's.

Does having your cells replaced somehow make you not Pelle? As if the stuff you are made of is essential to who you are.

Or is it memory? If I had a collection of all your memories, would I have you?

And my axe. I've had it for forty years. After breaking many a wooden handle, I replaced it with fibreglass. I found I was buying cut logs, so I replaced the felling head with a splitting maul. It's a blood good axe.

↪fdrake And my axe. I've had it for forty years. After breaking many a wooden handle, I replaced it with fibreglass. I found I was buying cut logs, so I replaced the felling head with a splitting maul. It's a blood good axe. — Banno

I don't put much stock in the Ship of Theseus. At most it shows that concepts can have fuzzy boundaries. All I wanted to do in the thread was to highlight that it's rebranded old hat, like the Matrix being a new way of phrasing the Cartesian daemon in skeptical arguments.

Understood.

@Pelle, there seems to be an issue with the notion that because the body changes, the self changes. Why should we think that? If you like, the question appears to confuse the physical body with individual.

Moreover, the introduction of "metaphor" is just odd. Metaphors describe something s something else, in order to draw attention to their similarity or distinctness. But to say that a man is a wolf is to say there is a man and there are wolves; otherwise the metaphor falls over. (see what I did there?) It is not at all clear what you think the two sides of your metaphor are...

This has to mean that we have metaphorically categorize our peers in such a way that trancends matter, otherwise we wouldn’t be able to even be a ”consistent” person for more than 10 years post-birth. — Pelle

Aren't neurons an exception? They aren't replaced for the most part.

The metaphor is divinity. Or divinity is like a massive self-portrait.

I didn't think of that. I guess that kind of solves the dilemma.

Plato made a useful distinction between stuff and arrangement, having noticed that wooden house and a stone house were both more comfortable abodes than a pile of bricks or lumber. Theseus found the same thing with his ship, that the material could all be replaced as long as the form was maintained.

Indeed there is a legend that Theseus had more than one ship; that he had a teleporter that went wrong, or possibly a couple of shipwrights and some spare lumber.

Is this fact evidence of our metaphorical nature? — Pelle

No, it's a misunderstanding of the actual biological science behind how our cells work.

And be careful taking everything Peterson says as any kind of truths. He's notorious for having argumentative flaws and fallacies. He has great insight into psychology, but he tends to move into philosophy with arguments that fall apart when picked apart.

didn't think of that. I guess that kind of solves the dilemma. — Pelle

But the neuron itself changes over time. It has to eat and excrete. What's your view on why it's the same cell over time when its material makeup is changing?

Couple more thoughts on myth and metaphor:

"Homer, it is essential to recall, was not just a poet; he was a teller of myths and legends. The mythmaking process had of course begun among the Greeks many centuries earlier, and it went on continuously wherever there were Greeks, always by word of mouth and often ceremonially. It was activity of the highest social (and human) importance, not just the casual daydreaming of a poet here, a more imaginative peasant there. The essential subject-matter of legend was action, not ideas, creeds or symbolic representations, but happenings, occurrences--wars, floods, adventures by land, sea, and air, family quarrels, births, marriages, and deaths. As men listened to the narratives, in rituals, at festivals, or on other social occasions, they lived through the vicarious experience. They believed the narrative implicitly. "In mythical imagination there is always implied an act of belief. Without the belief in the reality of its object, myth would lose its ground" -Ernst Cassirer, An Essay on Man""

--Finley, The World of Odysseus

The above bolding is mine, parentheses are native. So the answer to the question scholars ponder: did the Greeks actually believe the Homeric myths? may be both yes and no. To see the deep significance of the "yes" part of the answer, we might look at how 20th Century people used TV shows to tell themselves who they were and what was important. Questions left over: what is our mythology source today? How does the materialist climate of our world impact our self-metaphor?

What do you think?

I agree that he's not a top notch philosopher, but this argument is also psychological in nature. Can you elaborate on what I've misunderstood exactly?

The biological process of renewal of cells does not erase the information of the previous cells. It's essentially a copy. If you use the Ship of Theseus thought experiment, it describes how damaged parts get replaced with new parts. That's not how the body works. When a cell gets replaced it's essentially a perfect copy with healed parts. This process gets slower and worse over the course of a life and that's why we get old.

There is also nothing that says we are the same person over a period of time. We are constantly changing, based on the genetic makeup and our experiences that change our neurological makeup. But that doesn't mean it's metaphorical. Our body has a genetic blueprint that is informing our cells to renew cells according to what is established, so even if we renew all our cells, it's not happening in an instant and it's not replaced by anything new, only copies based on solid specifications. These specifications can be modified in order to adapt, like when we get a tan because our body needs to build up protection against UV light.

However, the neurological makeup does not change just because the cells change. The connections that make up the memories we have are still there and it's the neurological connections that create our consciousness, not cells. So even if our cells go through a process of dying and copying, the neurons stay in the formation that is necessary for our consciousness. The reason people start forgetting or having problems at an older age is that the neurons start to disintegrate when information becomes harder to process. Nourishment to the brain and the paths where information takes between neurons start to break down, new paths are harder to create, especially if there are little external stimuli.

It's an interesting theory and it's right in a sense but fundamentally it's wrong. — Jordan B Peterson

This is why Peterson has weak arguments. He frequently push things like "it's fundamentally wrong" while at the same time point out that "he is right in a sense". He muddies his arguments into a complete mess and that's why people compare him to Deepak Chopra. He is a brilliant psychologist, but the biggest problem is that he is an apologist and he muddies his own points by combining utter nonsense with findings that are truly scientific. That's why people have a hard time knowing whether what he says is based on science or his own ideological beliefs. Like when he pointed out that there are no real atheists since a true atheist is a murderer like in Dostoyevsky's writings. Utter bullshit. I've spent many hours listening to him but also listening to criticism against him and analyses of his rhetoric. It's dangerous to not have a critical mind while listening to him since he pushes his own personal ideas and convictions into areas of science, mixing them together so that those who aren't skeptics fall right into accepting his ideas. For a person who regularly warns about the mechanics of totalitarian states and their ways of manipulation, he uses similar mechanics to sell his books. It becomes clear that he isn't the brightest in the room when he gets pitched against other intellectuals in a discussion.

I was a huge JBP-head 5 months ago so I might've "rage-quitted" on you. But now I see that you were right about him.

An organism is not an assembly of independent parts. An assembly does not contain the history of its development. But an organism evolves by modifications of its systems, and can only understand itself by understanding the relationships that form its developmental history. Each generation of cells emerged from within the environment of the previous generation, and retains all of the dependencies that shaped that emergence. It has always been thus, so your identity already relies on its transformational history.