> Not really, we know that consciousness arises from the brain, and can change if it's damaged.

My point being that you already went from defining "you" with your body included to narrowing it down to your brain. How much else can you strip away? What if all your memories were gone, are you now dead and replaced by some other being?

> If it was replaced in such a way that the continuity is not broken, then I imagine you could slowly replace it all without necessarily impacting my experience of myself. However I don't personally believe that merely copying the information over to a new system would achieve the same, as I would be able to observe the copy go about a separate life, I would not have its experiences etc.

Easy enough to fix if we simply ensure the process is fatal. Why do you think there is a difference in outcome between a more gradual replacement and a wholesale one? I submit this is merely intuition not based in reality.

Do you believe that consciousness arises from the purely material, in which case there is no reason to believe that an identical copy (let's assume the copy process is fatal to take this "2 at once" situation out of it) is not you, or do you believe there is something, some essence of being, that cannot be copied?

> Massive assumption/assertion. Memories are structural within the brain, they are not mere information, they are substance. I experience this continuity of being, and it shapes me.

Structures in the brain are mere information, the same way bits on a disk are. You experience having a memory, you don't experience the events that formed it. Sometimes our memories aren't even real. If a memory is not based in reality that means that your past self didn't experience the events it records, yet it is still a part of what you consider to be yourself. If that is the case, then why are you so certain your consciousness has been continuous?

> Sure it will, but it will then lead a separate life, not one I will experience directly. So it is not me.

You don't directly experience anything but the now. You 5 minutes from now will only experience what you've just experienced as a memory, probably one that you 5 years from now won't even experience as a memory.

> That question is entirely orthogonal to whether or not it is the continuation of their own life. Which it's not, because they're dead and you've said as much. It could matter more to them for any number or reasons, from the biological drive to continue their line, to pure altruism. The consideration of whether a copied self would be you or not is entirely unrelated to how much people value themselves in relation to others, or why they might undertake such actions.

Again, I disagree, and I think you are unable to see it because you are stuck on this notion that who "you" are is some easily definable self-contained unique unit of being.

> Metaphorically, allegorically, narratively, certainly, but not in the concrete way we're talking about.

I disagree, I think it is true in a very concrete fashion. I think if you spent significant amounts of time thinking about it you would say so as well.

> You appear to have some sort of metaphysical belief around this area, that a copy of yourself could be considered yourself in some sort of wider consideration of self that includes not only potential clones and virtual copies but even whole groups of other people. To me, that doesn't gel in the slightest - if I get copied, if I have offspring, if I sacrifice myself for whatever reason, I still die. Those others may continue, and that's great, and that might even make the sacrifice worth it in your hypothetical altruistic death scenario. But I still die in that scenario. That's not immortality for me.

What I'm trying to say is that the very concept of "self" is an abstract notion and you are choosing to arbitrarily define it such that only the continued extension of your biological being could ever be immortality.