Universe is finite (or only countably infinite), and MWI is irrelevant (makes it larger, but doesn’t change the cardinality). When you die, you die. There may or may not exist near-but-not-exact duplicates outside of current-you’s lightcone.
is not one of your considerations. This seems most likely to me.
A more interesting counterargument is “distribution shift.” My next observer-moments have some probability distribution P of properties—representing what I am most likely to do in the next moment. If I die, and MWI is false, but chaotic inflation is true, then there are many minds similar to me and to my next observer-moments everywhere in the multiverse. However, they have a distribution of properties P2 - representing what they are more likely to observe. And maybe P ≠ P2. Or may be we can prove that P=P2 based on typicality.
If there is no identity substance, then copies even outside the light cone matter. And even non-exact copies matter if the difference is almost unobservable. So I think that countable infinity is enough.
I suspect we don’t agree on what it means for something to matter. If outside the causal/observable cone (add dimensions to cover MWI if you like), the difference or similarity is by definition not observable.
And the distinction between “imaginary” and “real, but fully causally disconnected” is itself imaginary.
There is no identity substance, and only experience-reachable things matter. All agency and observation is embedded, there is no viewpoint from outside.
The problem with observables here is that there is another copy of me in another light cone, which has the same observables. So we can’t say that another light cone is unobservable—I am already there and observing it. This is a paradoxical property of big world immortality: it requires actually existing but causally disconnected copies, which contradicts some definitions of actuality.
BTW, can you comment below to Vladinir Nesov, who seems to think that first-person perspective is illusion and only third-person perspective is real?
who seems to think that first-person perspective is illusion and only third-person perspective is real
The taste of cheese is quite real, it’s just not a technical consideration relevant for chip design. Concepts worth noticing are usually meaningful in some way, but most of them are unclear and don’t offer a technical foothold in any given endeavor.
The interesting part of QI is that the split happens at the moment of your death. So the state-machine-which-is-you continues being instantiated in at least one world. The idea of your consciousness surviving a quantum suicide doesn’t rely on it continuing in implementations of similar state machines, merely in the causal descendant of the state machine which you already inhabit.
It’s like your brain being duplicated, but those other copies are never woken up and are instantly killed. Only one copy is woken up. Which guarantees that prior to falling asleep, you can be confident you will wake up as that one specific copy.
There is no alternative to this, unless we require that personal identity requires something else than the continuity of pattern.
In big world immortality there are causally disconnected copies which survive in very remote regions of the universe. But if we don’t need continuity, but only similarity of minds, for identity, it is enough.
If QI is false, it must have theoretical cost:
Either:
Universe is finite and no MWI
Personal identity is based on some kind of destructible soul and my copy is not me
We use some variant of updateless decision theory, especially designed to prevent this type of problems (which is rather circular counterargument)
I’m not sure why
Universe is finite (or only countably infinite), and MWI is irrelevant (makes it larger, but doesn’t change the cardinality). When you die, you die. There may or may not exist near-but-not-exact duplicates outside of current-you’s lightcone.
is not one of your considerations. This seems most likely to me.
A more interesting counterargument is “distribution shift.” My next observer-moments have some probability distribution P of properties—representing what I am most likely to do in the next moment. If I die, and MWI is false, but chaotic inflation is true, then there are many minds similar to me and to my next observer-moments everywhere in the multiverse. However, they have a distribution of properties P2 - representing what they are more likely to observe. And maybe P ≠ P2. Or may be we can prove that P=P2 based on typicality.
If there is no identity substance, then copies even outside the light cone matter. And even non-exact copies matter if the difference is almost unobservable. So I think that countable infinity is enough.
I suspect we don’t agree on what it means for something to matter. If outside the causal/observable cone (add dimensions to cover MWI if you like), the difference or similarity is by definition not observable.
And the distinction between “imaginary” and “real, but fully causally disconnected” is itself imaginary.
There is no identity substance, and only experience-reachable things matter. All agency and observation is embedded, there is no viewpoint from outside.
The problem with observables here is that there is another copy of me in another light cone, which has the same observables. So we can’t say that another light cone is unobservable—I am already there and observing it. This is a paradoxical property of big world immortality: it requires actually existing but causally disconnected copies, which contradicts some definitions of actuality.
BTW, can you comment below to Vladinir Nesov, who seems to think that first-person perspective is illusion and only third-person perspective is real?
The taste of cheese is quite real, it’s just not a technical consideration relevant for chip design. Concepts worth noticing are usually meaningful in some way, but most of them are unclear and don’t offer a technical foothold in any given endeavor.
I think that first perspective is meaningful as it allows me to treat my self as a random sample from some group of minds.
The interesting part of QI is that the split happens at the moment of your death. So the state-machine-which-is-you continues being instantiated in at least one world. The idea of your consciousness surviving a quantum suicide doesn’t rely on it continuing in implementations of similar state machines, merely in the causal descendant of the state machine which you already inhabit.
It’s like your brain being duplicated, but those other copies are never woken up and are instantly killed. Only one copy is woken up. Which guarantees that prior to falling asleep, you can be confident you will wake up as that one specific copy.
There is no alternative to this, unless we require that personal identity requires something else than the continuity of pattern.
In big world immortality there are causally disconnected copies which survive in very remote regions of the universe. But if we don’t need continuity, but only similarity of minds, for identity, it is enough.
I don’t know about similarity… but I was just making a point that QI doesn’t require it.
I would argue that personal identity is based on a destructible body.
In MWI some part of the body always remains. But why destuctible?