alt Hacker News> What if they destroyed and reassembled only 0.5% of your brain? What's your dividing line? 0.36%? 0.0188%?
Apologies, I read too quickly and skipped over this. See one of my sibling comments. I concede this is problematic for my position and I need to think harder on how to solve it, but I don't think it's unsolvable. The placeholder answer is that there must be a certain level of damage -- the precise % probably doesn't matter as much as exactly which parts you destroy -- that is incompatible with keeping continuity.
For the rest, as a social construct, if we incinerate me to create a clone of me that is identical to the original at the subatomic level I agree that, for everyone else in society, it is me. But my self has still died and whatever replaced it is having its own experiences. And it matters very little what everybody else thinks: if tomorrow an imposter convinces everybody else that they are me, they aren't me for me. Their experiences aren't magically beamed to my brain.
Your tennis ball example is again a textbook dualist position. You can have a tennis match with different balls which is functionally identical to have it with the same ball, because the ball in the game is an abstraction that lives _outside_ the ball itself. But, assuming balls can feel when they are hit by the racket, the ball you used in the previous point and now is lying on the sideline does not feel being hit when the next point starts with another ball.
There's nothing you need to solve because definitions of words are subjective social constructs that are neither correct or incorrect. Definitions are axioms.
You have chosen to define the word "you" to require continuity, under some rubric. By that definition, a copy of you isn't really you. That's correct under your axiom, but it is incorrect under other axioms.
The functionalists I am trying to channel in this conversation have a different subjectively chosen definition of that same word, that is internally coherent assuming functionalism is a true description of the world.
You may wish to argue that their definition/axiom lacks utility, but that's subjective and cannot breach the boundary into a claim about objective correctness (logical deductions) under the axiom.
> You can have a tennis match with different balls which is functionally identical to have it with the same ball, because the ball in the game is an abstraction that lives _outside_ the ball itself.
This sounds like solipsism not dualism vs. monism. In non-solipsistic monism, social constructs can exist outside of a collection of minds, because other minds also exist.