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