One of the strongest findings in psychology is the fact that we are incapable of accurately estimating what we feel and thus what we believe. Most of us believe that we are "better than average" at driving; that we do most of the chores at home; that the things we own. should cost more than what people want to pay, that we are better people than we really are. The so-called illusory superiority bias is everywhere and it is a problem.
The illusion of superiority is problematic because we live in a society and we do not always agree with what other people think, want, or do. We believe we know better and we are even able to create systems that show we are right. Unfortunately. they can also do the same and show we are in the wrong. But how can two realities be true at the same time?
Directly after the second world war, Kenneth Arrow started his doctoral student. As he started to write his dissertation, on page two, he set a line in the sand, a frontier that he would not pass in his analysis. His line was not new but it is foundational to the idea of social welfare. The line you shall not pass is the one of "interpersonal comparison of utility".
The line Kenneth draw is not a line all-economists care for. Indeed, British economists from the utilitarian nature tread over this line all the time in the pursuit of "doing good better". For utilitarians, one person's happiness or suffering has the same units as anyone else. One can put people's experiences together and compare them to one another. But what one person defines as good might be seen as bad by others and thus myriads of contradicting measures emerge.
The problem emerges because crossing the Arrow's line is like dividing by zero. When one compares one person's utilities with another, anything can be achieved. And Murphy's law explains that when something can happen, it will happen. Therefore, the same data can be used for and against any position and we are left with a mess.
So, why care about Kenneth Arrow's line in the sand? Dave Chapelle said it better: when he was allowed to come back to our culture in his special "The Age of Spin" "you can't do comparative suffering. If you’re hungry, and your friend says, 'you know, people are starving in Africa,' 'so what [...]? I still want lunch'". You cannot compare what one action will mean to me with how you would experience it. That is trivial but the idea goes to many more spheres of life.
Dave Chapelle's "The Closer" special serves as a clear example. One mistake Chapelle does in his special --amongst many--yes many--is that Chapelle equates the pain of the African American community with the pain of the LGBTQI+ community. From his division by zero, he starts building an argument that from his standpoint is valid. But just as any other equation that starts by dividing by zero is ill-defined and marred with mistakes.
Pain hurts. Pain is one of the few experiences that precede the Cartesian "I think therefore I am". When in pain, I do not think but I am incredibly certain of my existence. It is a tragedy that we are not able to share our pain. But our empathy can be shared. As Chapelle quotes what "[people] do not need you to understand [them]. [They] just need you to believe that [they are] having a human experience.". Only in this way can we avoid treading over the line carefully laid by Kenneth Arrow over 70 years ago.
PS: I avoid directly linking Dave Chapelle's specials for clear reasons. Yet I do provide links to the exact quotes to avoid misreferencing.