EDIT: Mestroyer was the first one to find a bug that breaks this idea. Only took a couple of hours, that's ethics for you. :)
In the last Stupid Questions Thread, solipsist asked
Making a person and unmaking a person seem like utilitarian inverses, yet I don't think contraception is tantamount to murder. Why isn't making a person as good as killing a person is bad?
People raised valid points, such as ones about murder having generally bad effects on society, but most people probably have the intuition that murdering someone is bad even if the victim was a hermit whose death was never found out by anyone. It just occurred to me that the way to formalize this intuition would also solve more general problems with the way that the utility functions in utilitarianism (which I'll shorten to UFU from now on) behave.
Consider these commonly held intuitions:
- If a person is painlessly murdered and a new (equally happy) person is instantly created in their place, this is worse than if there was a single person who lived for the whole time.
- If a living person X is painlessly murdered at time T, then this is worse than if the X's parents had simply chosen not to have a child at time T-20, even though both acts would have resulted in X not existing at time T+1.
- If someone is physically dead, but not information-theoretically dead and a close enough replica of them can be constructed and brought back, then bringing them back is better than creating an entirely new person.
I think we can add a positive term as well: we gain some utility for happiness that once existed but doesn't any more. E.g. we assign more utility to the state "there used to be a happy hermit, then she died" than the state "there used to be a sad hermit, then she died". For certain values, this would be enough to be better than the state "there has never been a hermit", which doesn't get the "dead hermit" loss, but also doesn't get the "past happiness" bonus.
Hmm. You need to avoid the problem where you might want to exploit the past happiness bonus infinitely. The past happiness bonus needs to scale at least linearly with duration of life lived, else we want to create as many short happy lives we can so we can have as many infinite durations of past happiness bonus as we can.
Say our original plan was for every person who's died, we would continue accruing utility at a rate equal to the average rate they caused us to accrue it over their life, forever. Then making this adjustment puts us at multiplying their li... (read more)