Dying in Many Worlds

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This has filled me with the distressing thought that the badness of death might somehow be diminished because of this

I find this statement disturbing. This reads as if you'd really like X to be as horrible as possible to justify your preexisting decision of fighting X.

status quo bias

This has filled me with the distressing thought that the badness of death might somehow be diminished because of this. I am aware that Eliezer has written articles that seem to explain why this is not the case ("Living in Many Worlds" and "For the People Who are Still Alive,") but I have read them and am having trouble grasping his arguments.

This is a question that comes up (comparatively) frequently and it can be tricky to convey all the intuitions and conclusions in the space of a comment. My attempt to explain how this and related evaluations "mostly add up to normal" can be found in Preference For (Many) Future Worlds.

Short answer: If you believe you think a 50%/50% split of death vs gaining $200 is drastically better if done with a quantum coin than with a deterministic one then you are probably confused. It's technically possible to have coherent values where future Everett branches where you die don't count but it is a weird and arbitrary preference system. It is worth being very, very, sure about values, meta-ethics and physics before actually biting a bullet that encourages quantum immortality based decision making.

If my goal is to maximize some weighted average of everyone's utility function across the multiverse then, all else being equal, the death of someone who would prefer to have been alive is "bad". But if due to limited resources my choice is between having (all else equal) (a) lots of James-ems alive for one hour each + one that lives indefinitely or (b) just one James-em that lives indefinitely than I should prefer (a), assuming that the short lived James-ems would rather live for one than zero hours.

The fact that the existence of a many worlds multiverse means there are lots more people doesn't impact the "badness" of the death of an individual any more than the normal growth of the human population does since the more people there are the more likely that an experience which has given you joy has probably occurred in a pretty similar way before to someone else. (A parent seeing his child take her first step, having sex for the first time, consuming cocaine,...) (Would you be less bothered by the death of a man if you later found out that the man had an identical twin whom he never met?)

Your "Adding 200 years to your life that you would spend being stuck in a 'time loop'" example also seems analogous to the wireheading thought experiment.

Well, if quantum immortality worked, so would quantum insomnia, or quantum sobriety, or the like. Being distracted in the middle of the thought - there's you that weren't distracted, why you're not always him? Or: there got to be a parallel you that via sheer chance effectively did not advance a timestep, and he's more similar to you now than the one that did.

More generally, don't take things too seriously for mere lack of a counter argument. Fringe ideas are mostly discussed by their promoters, while detractors have bigger fish to fry.

Just some thoughts here... Not sure if they will solve the problem, but they might help you think about it:

1. Does it matter at all what form of "Many Worlds" you accept? Consider Max Tegmark's multiverse hierarchy: In Level 1, all your copies live in the same universe as you, but just widely separated (typically by a googleplex light-years or so). However, they could in principle communicate with each other, if they waited long enough. In Level 2, they live in different "pocket" universes, and can never communicate with each other, no matter how long they wait. In Level 3, they live in different branches of a quantum wave function. In Level 4, they occupy different mathematical structures; all such structures are real.

2. Do you think there are ANY real ethical questions where an acceptance of many worlds changes the answer? Frame each such question as a choice between two actions A and B, then imagine that the Earth, and its neighbourhood (a few nearby planets and stars, say) is all there is to reality, and all there will ever be. Let's say that the ethical action in that case is A. Are there any cases where the right action changes to B if there is a multiverse? Or if you can imagine a few (philosophers are good at that) are there any that you seriously expect to arise in your life?

1. The fact that the multiple worlds cannot currently, and probably never will be able to, interact in any significant way, makes it such that the moral worth of an action in one world out of many is exactly the same as what it would be if there was only one world.

This is actually a reasonably lay-friendly way of summarizing the case of the quantum-mechanical independence axiom. In non-interacting cases you should just do what you think is best for your own future (or past, but that's a decision theory feature :P ), treating the quantum-mechanical amplitude-squared as a probability.

But I think the main reason why this time loop stuff sounds bad is just because all this extra time loop "measure" has no causal connection to outside. It breaks the normal laws of physics, so of course you get abnormal results.

You want a reason why death would still be bad?

Pause for a moment and consider what an existence that continues beyond the moment of death would be like. You get shot in the heart - in one universe you die, in another you wake up in a hospital with severe medical problems. You die in 99.9% of universes you continue through for months, your body struggling to recover. You live in extreme pain that will not end, struggling with health issues that medical technology isn't sufficient to resolve. Most likely you have brain damage.

A thousand years later, your body is wracked with cancers that cannot kill you.

As you navigate rough philosophical terrain, always remember: everything adds up to normalcy.

This is another of those cases where I would argue the 'does it matter' line. Under MWI, there are countless universes containing many different states, some of which I would prefer less than others - which I have no control over. I can fret about them, worry about what could have been in those other forks, even draw some conclusions; but at the end of the day, the only decisions and actions I can appear to take are here, for my value function here, in this instance of the universe.

Just because there may be many worlds in which I don't die, that doesn't make my possible death here any less bad.

1. Assume your optimal dread - there is no moral reason not to kill others, with or without an advantage to yourself. There remain legal reasons not to kill others. Prison is living a long time repeating each day largely like the last, which you have identified as undesirable. It is practical and efficient not to kill others, and that is sufficient reason not to do so.

2. Everything is connected to everything else, but not equally connected. Butterflies flitting about in Kansas do influence ice patterns on Mars, but not as much (by far) as local conditions on Mars. Your local moral conditions matter more than across all time and space. You can act accordingly.

3. "I cannot know X as a fact" does not lead to "and therefore I must anti-X."

My own understanding of "Many Worlds" is not necessarily that everything which is possible does exist. We don't have (yet) any real explanation of the Born probability rule, it may come out that the worlds with very very low probability just don't "really exist", as the mangled worlds hypothesis claims.

Actions at macroscopic level are, most of the time, not affected by quantum noise. Unless you're very, very close to the threshold, a whole neuron firing differently in your brain has a very, very low probability (remember probability are multiplicative) which means that in most cases, all the worlds with significant Born probability (non-mangled ones) will have you acting the same (or the sociopath with a knife acting the same).

Only when a very small quantum-level event can have a huge macroscopic effect (like Schroedinger's cat experiment) do you really have worlds with different macroscopic outcomes. And yes, you can have such "chaos theory" effects, like the butterfly effect, even we don't artificially devise experiments that way, but they aren't frequent.

Disclaimer : I'm a computer scientist, not a physicist nor a biologist.

First, consider that if death isn't as bad as we seem to think it is, that's actually great news!! Because it's happened a lot already.

This has filled me with the distressing thought that the badness of death might somehow be diminished because of this.

This sounds like you're experiencing motivated cognition, which makes me reluctant to say that, in fact, I don't think you need to worry. It sounds to me like this has the same "resolution" as quantum suicide: what you really should care about is your measure (how much of you there is in the multiverse, whatever that means). Reduction in measure seems about as bad as dying in non-multiverse scenarios; every (information-theoretic) death permanently shuts you out of huge regions of the multiverse, and causes googleplexs of your friends and family members great emotional distress.

Plus, things are only guaranteed to happen in the multiverse if they can happen, and you don't necessarily know what can happen...

No MWI, no problems of this kind.