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.
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.