I used preferences about restaurants as an example because that seemed like something people can relate to easily, but that’s just an example. The theorem is compatible with hedonic utilitarianism. (In that case, the theorem would just prove that the group’s utility function is the sum of each individual’s happiness.)
In this case, I think it’s harder to argue that we should care about ex ante expected individual hedonistic utility and for the 1st and 3rd axioms, because we had rationality based on preferences and something like Pareto to support these axioms before, but we could now just be concerned with the distribution of hedonistic utility in the universe, which leaves room for prioritarianism and egalitarianism. I think the only “non-paternalistic” and possibly objective way to aggregate hedonistic utility within an individual (over their life and/or over uncertainty) would be to start from individual preferences/attitudes/desires but just ignore concerns not about hedonism and non-hedonistic preferences, i.e. an externalist account of hedonism. Roger Crisp defends internalism in “Hedonism Reconsidered”, and defines the two terms this way:
Two types of theory of enjoyment are outlined-internalism, according to which enjoyment has some special ’feeling tone’, and externalism, according to which enjoyment is any kind of experience to which we take some special attitude, such as that of desire.
Otherwise, I don’t think there’s any reason to believe there’s an objective common cardinal scale for suffering and pleasure, even if there were a scale for suffering and a separate scale for pleasure. Suffering and pleasure don’t use exactly the same parts of the brain, and suffering isn’t just an “opposite” pattern to pleasure. Relying on mixed states, observing judgements when both suffering and pleasure are happening at the same time might seem promising, but these judgements happen at a higher level and probably wouldn’t be consistent between people, e.g. you could have two people with exactly the same suffering and pleasure subsystems, but with different aggregating systems.
In this case, I think it’s harder to argue that we should care about ex ante expected individual hedonistic utility and for the 1st and 3rd axioms, because we had rationality based on preferences and something like Pareto to support these axioms before, but we could now just be concerned with the distribution of hedonistic utility in the universe, which leaves room for prioritarianism and egalitarianism. I think the only “non-paternalistic” and possibly objective way to aggregate hedonistic utility within an individual (over their life and/or over uncertainty) would be to start from individual preferences/attitudes/desires but just ignore concerns not about hedonism and non-hedonistic preferences, i.e. an externalist account of hedonism. Roger Crisp defends internalism in “Hedonism Reconsidered”, and defines the two terms this way:
Otherwise, I don’t think there’s any reason to believe there’s an objective common cardinal scale for suffering and pleasure, even if there were a scale for suffering and a separate scale for pleasure. Suffering and pleasure don’t use exactly the same parts of the brain, and suffering isn’t just an “opposite” pattern to pleasure. Relying on mixed states, observing judgements when both suffering and pleasure are happening at the same time might seem promising, but these judgements happen at a higher level and probably wouldn’t be consistent between people, e.g. you could have two people with exactly the same suffering and pleasure subsystems, but with different aggregating systems.
I’m personally more sympathetic to externalism. With antifrustrationism (there are actually arguments for antifrustrationism; see also my comment here), externalism leads to a negative hedonistic view (which I discuss further here).