Dominik Teiml on his blog wrote an article, in which he argues that an interpersonal comparison of benefits is possible. But he is wrong.
Imagine Peter and Paul.
Petr likes goulash - he likes to eat it. He finds this food useful, he feels the benefit.
Pavel doesn't like goulash - he doesn't like eating it. He does not consider this food useful, it does not feel useful.
Utility is not a property of things, but the result of people's evaluation - something that comes from us, not from things. The thing has no objectively definable benefit.
So why can't the benefits be compared between people?
Needs and preferences
One uses things that one finds useful in order to meet some of one's needs. For example, I am hungry - I have a need that I want to "fulfill", satisfy. I want to eat. Is my hunger the same as your hunger? Is my hunger the same as the hunger of an African child? Is my hunger the same as my neighbor's hunger? It's not.
My hunger is completely different. I like different food, I prefer different tastes. If my hunger is different (incomparable - it is neither worse, nor better, neither any, nor any) than my neighbor's hunger, my benefit in fulfilling that need is different (incomparable) to my neighbor's.
Or take the example of Henry from the fairy tale The Princess of the Mill. Can we compare its "benefit" with an emperor drowning in depression?
After all, Henry is obviously happier than an emperor. Or not?
But what is happiness? Is there an objective value definition of happiness? Is happiness health? Family? Money? No one knows. Do we know so objectively that Henry is happier than an emperor? We don't know. We only know this from the position of our value court.
He can also be a happier emer - what if the emar's happiness lies in "being different", "being depressed" and "being the center of attention"? The emeraldy makes a certain community accessible to people - and what if the emara's "happiness" lies in that community? After all - an emperor would not be an emperor if it did not benefit him - Happiness.
It is clear that the statement that Henry is obviously happier than an emperor is mere subjective judgment of value. There is no objective comparison of happiness. If we identify happiness with utility, we get the result: an objective comparison of utility is not possible.
There is no objective comparison of needs and human goals. We do not know which goals are objectively "worse" and which are objectively "better". And if we think so, it is a value-colored statement.
The benefits are based on the needs and preferences of individuals. I, as an individual, have my specific needs and preferences that are completely unique. They are made independent of other people, depending on my own decisions. It is not shaped "above" for us, it is not dictated to us. It comes from us. There is no "social benefit" that unites people among themselves. It is not possible to compare the benefits between people.
Perception of time and place
Benefit is the result of human judgment, its knowledge, information. It is a purely human thing. As such, it is linked to a specific time and place - a specific time and place exists and is perceived only in the sphere of human-individual action. Time is perceived subjectively, instead of as well. And only to this subjective perception is the benefit attached. Utility is thus a subjective thing, it cannot be compared. It cannot be said that Peter likes goulash, he benefits so much from it than Paul, who does not like to benefit. What if Peter is thirsty? What if Paul is hungry and only goulash is available? What if…
We cannot compare benefits. Any interpersonal comparison of utility is also a comparison of utility over time and place - but in time and place the perception of benefit is constantly changing. It is not possible.
It's like an interpersonal comparison of happiness. What is "luck" for whom? But when? Where? Can we somehow "compare" it? It is the same. We can say that something is something for someone from our value point of view. However, this statement is the only thing we can do. The comparison is already a value (subjective) court.
To say that goulash is more useful to Peter than to Paul, is not an objective but a subjective value claim.
Any admission of the interpersonal comparison of benefits is thus an admission of the possibility of the existence and functioning of socialism and central planning "Under the conditions of high-performance computers" - FA Hayek refuted this argument several decades ago…