The St. Petersburg case does involve infinitely many possible worlds, in the sense that its probability distribution is not finitely supported, or in the Kripke-semantics sense. But I agree that infinitely many possible worlds is an extremely common and everyday assumption (say when modeling variables with Gaussians), and that similar issues come up that perhaps could be handled by similar solutions.
I do think it’s reasonable to call those cases “infinite ethics” given that they involve infinitely many possible worlds. But I definitely think it’s a distraction to frame them as being about infinite populations, and a mistake to expect them to be handled by ideas about aggregation across people.
(The main counterargument I can imagine is that you might think of probability distributions as a special case of aggregation across people, in which case you might think of “infinite populations” as the simpler case than “infinitely many possible worlds.” But this is still a bit funky given that infinitely many possible worlds is kind of the everyday default whereas infinite populations feel exotic.)
The St. Petersburg case does involve infinitely many possible worlds, in the sense that its probability distribution is not finitely supported, or in the Kripke-semantics sense. But I agree that infinitely many possible worlds is an extremely common and everyday assumption (say when modeling variables with Gaussians), and that similar issues come up that perhaps could be handled by similar solutions.
I do think it’s reasonable to call those cases “infinite ethics” given that they involve infinitely many possible worlds. But I definitely think it’s a distraction to frame them as being about infinite populations, and a mistake to expect them to be handled by ideas about aggregation across people.
(The main counterargument I can imagine is that you might think of probability distributions as a special case of aggregation across people, in which case you might think of “infinite populations” as the simpler case than “infinitely many possible worlds.” But this is still a bit funky given that infinitely many possible worlds is kind of the everyday default whereas infinite populations feel exotic.)