> utility scales of different persons are comparable.

but a decision is only made by one person, so only that person's utility function matters. A different person, using their own utility function, would come to a different conclusion and make a different choice.

So while there's no universal utility function, it doesn't matter as long as the decision maker's utility function exists (and it does, by tautological argument). In the article, the utility values of 80 and 40 for the boys are the outcome of the parent's utility function. The boys don't get a choice, and so their utility functions don't matter.

> So while there's no universal utility function, it doesn't matter as long as the decision maker's utility function exists (and it does, by tautological argument). In the article, the utility values of 80 and 40 for the boys are the outcome of the parent's utility function.

Yes, but ... the argument in the article presupposes fixed differences in utility when ascribing choices to priority, equality, and pure utilitarian views. Is it not easier to just say that the parent values improving the situation of the disabled boy more, and thus the utility of this improvement to the disabled boy's situation is higher in one parent's view but not the other?

Nearly any parent will choose a massive benefit from son A's perspective at the cost of a tiny expense to son B (looks utilitarian!). Nearly any parent will prioritize a sibling who is less well off in some circumstances. Nearly any parent will give the two sons equal slices of cake when they value them equally. But is it not easier to ascribe different utilities to these different circumstances instead of different allocation functions?

That's fair. The article uses phrasing like "the disabled boy has a total utility of 40", suggesting that the utility is an attribute of the boy, but I guess it would become wordy and repetitive to phrase it any other way.

Is the concept of utility then anything other than tautological? If I understand what you're saying, it's roughly that, "A person chooses things, and since I imagine that their choice process can be caricatured as a linearized ranking system, a utility measure must exist for them".

I'm not saying that's a necessarily false model. But it strikes me as such a crashingly unsubtle simplification that I'd want to see a ton of data demonstrating that's really how it works. As opposed to just being something that academics assume so they can write bold, confident papers with conclusions that they like.

Von-Neumann Morgenstern utility is mathematically precise; there is a real-numbered utility function such that maximizing utility is equivalent to choosing the correct lotteries according to an agent's preferences. So long as every decision one can have a preference about can be stated as a preference over expected outcomes (e.g. 50% chance of ice cream over 30% chance of cake, or related to the article: 90% child-one succeeds and 70% child-two succeeds v.s. 85% child-one succeeds and 74% child-two succeeds) then the utility function exists.

Humans do not have utility functions. We have a lot of circular or contradictory preferences and other ancient machinery in our brains, and especially we do not reason about probabilities and expected outcomes accurately enough. We might be able to grow into having a utility function while still being happy about our preferences and without changing our humanity for the worse.

> The argument presented in the article, as well as ideas like the "utility monster" are based on the idea that the utility scales of different persons are comparable.

The article makes no implicit or explicit statement about how one defines a/the utility function, but I see no reason to believe the author thinks it's a universal function.

As indicated in the sentence directly following your quote.