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Utility is a fundamental concept in decision theory. Arguing it cannot exist is the opposite extreme to arguing that homo economicus, with superhuman evaluative strategies and no gaps in rationality, exists.

People can compare their current situations to relative improvement, and often those are transitive (though not always). So in most reasonable cases the mathematical axioms needed for utility to be defined exist in a reasonable way, allowing for comparison through a formalized utility function.

One can certainly mathurbate themselves with utility, and many do, but ultimately utility is a discussion to simplify communication (instead of primitives) about why people make preditible choices. It extends pretty quickly to revealed preferences.

Of course, asking where preferences come from in the first place is a third rail.

I disagree. OP is correct. Utility is a rhetorical construct. Sometimes it works well for describing morality, decisions, etc. Sometimes it's crammed in.

Using it to describe the two sons decisions is cramming it in.

> Utility is a rhetorical construct

It's a mathematical construct to show ranking of points in a topological space. With two simple axioms, comparability and transitivity, it is fairly well defined mathematically, though it typically enters the extrapolation zone at extremes.

But if the definition is barely more fleshed out than "some cost function", then the difference between utility, priority and equality as discussed in the article collapse; they're all the same thing. Cost functions, aka: utility.

Cost functions are typically the dual for utility maximization under cost constraints.

You are correct in that they are usually mathematically equivalent.

Yeah, I was struggling the find the best terminology for that, but given the ambiguity of the term "utility" in this context I though it better to avoid that ;-).

I'm certain nobody argues with you on that point. The question is: what does the fact that numbers can be ordered entail for ethics?

I’ve always heard utility in the context of a utility function. Basically:

f(u) = Wx*x + … + Wz*z, where x and z are variables that are impacted by decisions and constraints. Each variable is weighted for importance by the person / group using the utility function.

So for a home buyer needing to get to a city, the utility of the house improves as the location to the city gets better, subject to the constraint that it’s not in the river. A home buyer utility function might also weight cost, neighbors, amenities, square footage, local pollution, safety, and any other meaningful variable for the buyer.

Turning this into a quantitative formula can be cramming it in and quite hand-wavy, but ultimately it’s up to the person optimizing for their own utility to put in the variables and weights. These will be shifted by the person’s moral code (e.g. A Jewish person may highly value living in the city’s Eruv).

On a political note, big government supporters believe the federal government can define a utility function for the country that is best for the greater good. People who believe in smaller federal government and governing at the local level believe the utility functions should be defined at the individual level if possible - subject to the constraints one does not infringe on others’ rights. There are benefits to both sides (some things we can’t achieve if everyone acts independently, some things create externalities, some things have too many edge cases and unintended consequences).

I think the extreme of a shared utility function is communism, with an idea of central planning.

If the math of utility is interesting to you, check out Hal Varian's microeconomics book (he is/was chief economist at Google) or the intro grad text for microeconometrics Mas-Collel, Winston, and Green.

Utility theory's primitives are defined before the actual function.

Social choice theory is covered in MWG -- arrow's impossibility theorem is absolutely fascinating!

The field of mechanism design relies heavily on utility theory -- it's effectively the inverse of game theory, or, how to structure systems and incentives to get desired outcomes.

>Utility is a fundamental concept in decision theory. Arguing it cannot exist is the opposite extreme to arguing that homo economicus, with superhuman evaluative strategies and no gaps in rationality, exists.

It's probably more like arguing that leprechauns don't exist.

The burden of proof [for its existance] is on those making up those "fundamental concepts in decision theory". I won't be taking it for granted just because they came up with it.

In any case, I'm not saying utility can't exist. I'm saying some universal utility can't exist, or if you wish: sorry, guys, you can't determine my utility function for me. I'll do it myself, thank you very much.

>So in most reasonable cases the mathematical axioms needed for utility to be defined exist in a reasonable way, allowing for comparison through a formalized utility function.

If we could have a "formalized utility function" for "most reasonable cases" we'd hardly have different morals, political parties, and so on...

It's mostly irrelevant (trivial) cases that have formalized utility functions. Everything else is political, that is up for debate based on interests, preferences, morals, and so on -- and especially based on idiosyncrasy.

Even maximing one's life/health is not some constant. Many prefer to smoke, drink, eat, knowing fully well it might have them, because their utility function favors enjoyment over life span. Others might sacrifice their life for some cause or another.

And yet, the theory of utility works well under extensions of bounded rationality, with full acknowledgement of time inconsistent preferences.

Utimately utility is a simplifying model of human behavior.

> we'd hardly have different morals, political parties, and so on.

This touches on where preferences come from, which utility theory is mainly silent on.

> you can't determine my utility function for me. I'll do it myself, thank you very much

You have now stated that utility exists.

At no place should any argument depend on some universal utility function that applies to everyone. The idea of a universal utility function is a useful simplification for some beginner classes, but quickly becomes useless for anything in the real world. In fact if there were a universal utility function(s?) economics wouldn't be hard to study, just a simple optimization problem that businesses would use.

All that we need is for everyone to assign utility in some way. It doesn't matter if your function omits critical factors, applies the wrong weighting, or otherwise is a decision you come to regret. (note that this hindsight might be wrong because you don't really know what your regrets would be had you made the other decision) All that matters is at some point you weight all the factors you consider important and make a decision based on them. You can come up with a complex formula to put numbers to it, or just go with a "gut feeling" (in many cases others are involved - perhaps a spouse). Regardless you have made a utility function for your situation.

> You have now stated that utility exists.

Only in the context of a single person. 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.

This is not the same thing as a universal utility function, but almost as outlandish.

> 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.

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.

> 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?

> 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.

>You have now stated that utility exists.

I never said it doesn't. In fact I opened this thread by writing "The very idea that there is some measusable "utility" to compare in the two cases, independent from your moral values and sentiments, is inane".

That is, it's the independent from the person, measurable, utility (as per the example in TFA/theory) that I called BS.

>but quickly becomes useless for anything in the real world

My sentiments exactly.

>All that matters is at some point you weight all the factors you consider important and make a decision based on them. You can come up with a complex formula to put numbers to it, or just go with a "gut feeling" (in many cases others are involved - perhaps a spouse). Regardless you have made a utility function for your situation.

Sure. But none of this has much to do with the theory as presented in the post's examples...

> The burden of proof [for its existance] is on those making up those "fundamental concepts in decision theory". I won't be taking it for granted just because they came up with it.

What? It's trivial. People want things. Things that satisfy wants have utility. You can just look this up. It's pretty basic to modern economics and philosophy.[1]

1. https://en.wikipedia.org/wiki/Utility

You're just defining satisfaction of wants as utility. "Things that satisfy wants have utility" is a statement of a definition, not a synthetic claim. There are plenty of measures of utility other than hedonic ones (or volitional ones, or whatever exactly your definition is specifying).

Yes, because that is what's meant by the word in this context.

I'm aware, but my point is that you're not making a synthetic claim - you're not proving the (axiological) meaningfulness of a concept. You're just saying "I use this word 'utility' to describe the satisfaction of wants".

It doesn't really answer any of the questions that were posed, about how you can measure and compare the 'want-satisfying-ness' of different things. How do you measure the degree of want? How do you measure the degree to which a want is satisfied? How do you compare those across human beings?

If by 'trivial' in your original comment you meant 'trivial' in the technical sense[0], then I'd agree with that. "I define 'utility' as 'satisfaction of wants'" is a statement that neither predicates nor proves anything of the world.

[0] https://en.wikipedia.org/wiki/Triviality_(mathematics)

It does answer the questions by reformulating them in exactly the way you did, which immediately highlights the GPs confusion: They somehow missed the subjective and relative aspects of the concept as it is used. There is no objective and absolute measure of want-satisfying-ness (or whatever).

> It's probably more like arguing that leprechauns don't exist.

> In any case, I'm not saying utility can't exist. I'm saying some universal utility can't exist, or if you wish: sorry, guys, you can't determine my utility function for me. I'll do it myself, thank you very much.

This is what I'm responding to.

You call it trivial, but the second sentence says, "Its usage has evolved significantly over time"; both can't be true. And the criticism section makes some good points: https://en.wikipedia.org/wiki/Utility#Discussion_and_critici...

I also think there are a number of questionable assumptions behind it, and even your simple version of a supposedly trivial concept doesn't match the current official definition well.

So to me this isn't so much an obvious fact about the world as a synthetic cornerstone to a worldview. Sort of like Peano's construction of the integers, or the way theists talk about the things that are "pretty basic" to their religion. Those things feel trivial to their adherents, of course. But the rest of us can find sweeping dismissals like yours as very offputting.

"In any case, I'm not saying utility can't exist. I'm saying some universal utility can't exist, or if you wish: sorry, guys, you can't determine my utility function for me. I'll do it myself, thank you very much."

The article does not posit a "universal utility function", nor does it require determining anyone's individual utility function. It merely requires that utility functions exist and that a comparison of the resulting utility is meaningful.

"If we could have a "formalized utility function" for "most reasonable cases" we'd hardly have different morals, political parties, and so on..."

Only if you have a universal utility function. Which you are the only one proposing.

Right, but if the essence of the question is by what function you measure utility, then the question as posed by the article is a moot point. utility, priority, equality - they're just slightly different cost functions for the utility. And it's not even the case that they're well-defined and clearly separated; some level of interpretation is going to be required regardless.

For example, people routinely act as if money has a non-linear utility; we'll insure ourselves against stuff partially because being destitute is worse than the mere loss of money might suggest; i.e. each additional dollar is worth less.

But exactly how you define those non-linear relationships, especially once you include stuff like happiness, health, and intend to aggregate over multiple individuals is clearly tricky, and it's not reasonable to expect any one simplified model to work well in all situations in reality. It's not even reasonable for that to be knowable or computable.

So it's both perfectly reasonable to consider it ludicrous to label one such scenario as having "40" and "80" utility without having had the critical discussion of what that utility is measuring, while also conceding that the concept of utility is reasonable and... sometimes... enlightening.

Thanks, this was a really insightful comment (as someone who spent years of my life getting a graduate philosophy degree, before doing something more 'useful'). I think the concept of utility is clearly, uh, useful, and the reason that it's aversive to people is that they tend to bundle it up with a lot of the (sociologically, not logically) related views, which tend to be more problematic.

Hedonic utilitarianism in particular turns a lot of people off, and partly for good reason. I'm deeply ambivalent about it, and I think the surrounding debates, and the assumed primacy of moral intuition in applied cases, are far harder and more open questions than most people reckon. But I can still see how examples like utility monsters, or gang rape being morally superior to garden-variety rape because there are more people to enjoy it, might make people feel like it's really on the wrong path.

Those examples are hilariously egregious, yeah! It's slightly taboo in polite conversation to see increased utility there, yep. Thanks for the kind words, too.

Utility can be intrepret in many ways. Look at the social sciences and how they see minorities, e.g. disabled people. From the social scientist's view, one "utility" of these people is that they stabilize societies because they trigger empathy, which would otherwise be largely missing in a society that only aims for optimization. I want to emphasize that I find it generally humilitating to talk about utility and humans in one and the same sentence.

think of it as a label for the process by which you decide to prioritize cleaning up different areas of your house -- and utility becomes a rational and humanizing thing.

using it to prioritize your relations forces you to grapple with subjective and irrational things such as personal prefs, aspirations etc. so.. also rational and humanizing.

this leaves using it to mess with others without them participating in weight-setting (democracy as a weight discovery mechanism?), that's where it gets messy.

i fail to see where any of the three facets above make it humiliating to see where 'by priority' the most relative improvement can be made. i mean, this is all just fine talk about something innate to nature, no?

I don't think GP is arguing that utility doesn't exist. I believe the GP is arguing that the OP is making arguments as if utility weren't subjective.

If you can attach a number to decisions, you can just do the math. The thing is, attaching a number to make a non meta argument about decision making can be bollocks since the actual utility can be -9999999 for me or 9999999 for you. An utility function is a function of the decision making agent

See the "independent from your moral values and sentiments, is inane" bit

Yes, utility as a concept in decision theory is great, but it’s not the same as the concept by the same name from utilitarianism. In my understanding, coldtea is doubting not decision theoretic utility functions, but utilities as they are used here.

Most importantly a decision theoretic utility function is only defined up to any positive definite transformation. Inter-agent comparisons like "Imagine that the gifted boy has a total utility of 80, and the disabled boy has a total utility of 40” don’t make any sense in terms of decision theoretic utility functions.

If someone has a special preference for egalitarian outcomes, this should be included in their utility functions.

Telling someone their utility values for each of the choices is equivalent to telling them their preference. Asking for their preference afterwards is pointless, they have already been told their preference.

When the article talks about utility in its examples, it is not talking about some universal objective utility that all would agree on. It is talking about the utility that the person making the decision assigns which will depend on their moral values and sentiments.

> What if you don't want to help build a society that neglects the needs of disabled people because of their lesser contribution, and thus your utility function - ie. your desired goal maximization includes helping the disabled son?

Then you'd have a case where utilitarianism and egalitarianism produce the same outcome which is great when you can achieve it, but not very useful in an article that is trying to talk about when utilitarianism and egalitarianism produce conflicting outcomes.

Utilitarianism can never be in conflict with your preferences whatever they may be. This is by definition.

If the utility values would conflict with your preferences, then those were not the correct utility values to begin with.

> In the examples, it is assumed that utility == favoring gifted son

This is a misreading of the article, which assumes utility in helping either son. The point is that while a 'pure' or 'fundamental' utilitarianism would simply say one should choose the option that maximizes the total of this utility, the priority view says there may be rational reasons for using a weighted sum of the utilities, or include additional terms.

This article should be seen in the context of moral philosophy, which (naively) might be thought of as an attempt to find a rational basis for ethics, but more realistically should probably be seen as probing the extent to which one can be rational about such matters.

> The whole thing is presented as only a matter of whether you value utility or not.

That is because it is a continuation of a discussion over the utility of utilitarianism that has been going on, in some form, since antiquity, and which picked up pace after Bentham formulated his Principle of Utility [1].

There are quite often cases where one can have a somewhat objective utility function, and this comes up repeatedly in urban planning, as it is often the case that a project that is beneficial to the community as a whole often has a downside for some (usually those living near where the project will be sited.) A purely utilitarian view almost always favors putting the burden on those who have little left to lose, and the priority view says there can be a rational basis for choosing an alternative.

Somewhat ironically, the priority view argues against what you seem to find objectionable in simple utilitarianism. Perhaps it is also worth pointing out that when utilitarianism was first proposed, it was rather radical; prior ethical notions were mostly about obeying your betters (on Earth and in Heaven.)

[1] https://human.libretexts.org/Courses/Lumen_Learning/Book%3A_...

Inane, perhaps.

I don't think these ideas can be separated from their time and place. Like most philosophical/intellectual movements, a lot of what they are is objections, dialogue and alternatives to previous ideas or competing ideas.

To us, 2-300 years later, we don't necessarily need a concrete basis for secular morality. We also don't expect morality to be reducible to a simle principle like F=ma.

To them, they were in a period where medieval theology was being replaced by secular philosophy and science. They expected morality to be solved like Newton and Galileo had solved problems in their domains. We don't expect this anymore.

I agree, i think it's far more likely that those favoring the disabled child are simply rejecting the artificial and abstract notion of utility described in the hypothetical, and going with their own experience. Which is that the real-world utility to the disabled child is in fact far higher. I don't think anyone could read that hypothetical (particularly in the age of the Internet) and believe that putting a gifted child in a city would be significantly harmful to them.

now you're touching on the limits of knowledge of those making choices and might be tempted to rate them. that's out of scope for the deciders at that level, the parents in that story. ... the point is that they know the situation best. and that utility lets them quantify the subjective to test-run the rationalizations going into their decisions.

e.g. "maximising sum(log(utility))" like the comment on the article said. the only thing strange here is that philosophy deals with qualitative, not just quantitative domains. thus they tell these stories. :)

True, but the parents in the story are imaginary---their decision-making is not being tested. Rather, it's the observer who is being tested. But the story is so contrary to experience that is does not do what the premise of the article suggests it does: distinguish observers that care more about equality than utility. Because the premise is flawed (ie, that this is a valid test), it tends to moot the rest of the article drawn from that premise.

The city vs suburb is just a lazy shorthand to setup the hypothetical. If the issue is transportation time to a hospital, you could live in a suburb near a hospital.

Some cities have excellent schools and some cities have awful schools and the same for suburbs.

To make my own lazy shorthand, would you consider it significantly harmful if a gifted child is placed in a classroom where everyone else is behind grade level and the instruction is paced accordingly vs a classroom where instruction is paced at grade level or perhaps at an accelerated pace? If that's not enough, what if it's a rougher school where physical altercations are the norm.

Sure, these days, there's the internet, the magical cornucopia of knowledge, but it can be hard to get the motivation to use it.

All that said, my personal utility function measures a lot more utility for independence than for education and what not. If a better situation for the disable child may result in more independence for the disabled child, the gifted child is just going to have to make the best of a situation that's been decided for someone else's best interest.

You can patch it back up by replacing utility with something specific, although at the cost of its mysterious air. Let's say that the smart kid will... cure cancer if he's in the suburbs, but become a drug kingpin if he grows up in the city.

It's just a theoretical value that philosopher's use to avoid the subjectivity of utility when making an argument. They are well aware it's subjective, but the subjectivity of utility is agreed upon and not of interest in these thought experiments.

When someone says, "if I had a million dollars, I would take a trip around the world!" you don't chastise them for not having a million dollars. Well, unless you're my mother ;P

If the “utility score” was an overall rating for quality of life, it might change your view? Whether I assign a numerical or qualitative value is (arguably) arbitrary: as a parent, I’m still calculating which actions I should take based on some scoring mechanism.

>as a parent, I’m still calculating which actions I should take based on some scoring mechanism.

The key is that you do it: it's not imposed upon you in the form of a normalized/universal scoring rule.

Which the article doesn't argue against. Instead, it assumes for the sake of argument that you've made a utility calculation whereby favoring the disabled son is the worse choice.

> What that "utility" unit would measure?

Well, that's up to you, is it not? Who else could determine what you value and to which degree?

> The very idea that there is some measusable "utility" to compare in the two cases, independent from your moral values and sentiments, is inane.

There's philosophical charity, in the sense of your ability to put aside your judgments to listen and gain knowledge. That can be measured. Simply ask "You know this?" and count how many no's. There's some things we will never know that are very important, like dying or being created. From those you can get to real altruism. Caring for others is the natural state of humanity and makes humans strong, nice and beautiful. Selfishness is unnatural, weak, hateful, and ugly. Whatever created you cared about you and helped you, gave you the capacity for joy and happiness. Sooner than you think you will be abandoned by everything and those will be taken away and you will be in need. It's better for you to help others than just helping yourself. Personal sacrifice is not needed. It's not okay to be hurt or be a victim. Interior motives are irrelevant. It's better if everyone in the world is cured than just you while everyone else dies.