This is basically just the Coase Theorem. What Coase made clear is that externalities are fundamentally symmetrical; allowing the neighbour (Clarisse?) to have the peace and quiet she wants means that A cannot play the music at the volume she wants, and vice-versa. The "ethical duties," at least in a normal sense, are symmetrical too; why is A obliged to put up with quiet music for C's benefit? Why isn't C obliged to put up with loud music for A's benefit? Indeed, one of the examples cited in Coase's original paper was a confectioner's machine causing shaking in a doctor's surgery, which is essentially analogous to this.
Let's get down to brass tacks. If C doesn't want A to play music so loud, but it's A's right to do so, why should A oblige? What is in it for A? That doesn't mean C necessarily has to make some monetary payment, but is C going to (say) bake cookies for A? Or at the very least, can C credibly promise likely future benefits for A from good-neighbourliness, etc? And note that those benefits need to be greater than the utility A gets from playing the music at such a volume.
On a practical level, I would ask - what is the relationship like between A and C? Is C normally a good neighbour to A, and is now making an unusual request, or is C constantly bombarding A with such requests? Is C respectful of the fact that she is asking A to go out of her way to help, or is she demanding? Is she willing to "sweeten the deal" for A by doing (or refraining from doing) something else to please A, or is C such an exquisite bundle of neuroses that she could never do anything for anyone? Does C bother her neighbours, and how does she respond to similar requests herself? And so on.
Application of this to any other situations is left as an exercise for the reader.
Economically speaking, externalities are fundamentally symmetrical; morally, not so much.
There's a defeasible presumption that if I project matter and/or energy into you, and that directly causes you to suffer, I'm in the moral wrong. Sound waves are energy, of a type which can cause biological damage, and at lower levels (varying by person) can still cause the pain that signals damage. So this counts as direct causation of suffering, in the relevant sense.
(Indirect causation of suffering can get tricky. For example if the sounds that I emit cause you t...
My hidden secret goal is to understand the sentiments behind social justice better, however I will refrain from asking questions that directly relate to it, as they can be mind-killers, instead, I have constructed an entirely apolitical, and probably safe thought experiment involving a common everyday problem that shouldn't be incisive.
Alice is living in an apartment, she is listening to music. The volume of her music is well within what is allowed by the regulations or social norms. Yet the neighbor is still complaining and wants her to turn it down, claiming that she (the neighbor) is unusually sensitive to noise due to some kind of ear or mental condition.
Bob, Alice's friend is also present, and he makes a case that while she can turn it down basically out of niceness or neighborliness, this level of kindness is going far beyond the requirements of duty, and should be considered a favor, because she has no ethical duty to turn it down, for the following reasons.
1) Her volume level of music is usual, it is the sensitivity level of the neighbor that is unusual, and we are under no duty to cater to every special need of others.
2) In other words, it is okay to cause suffering to others as long as it is a usual, common, accepted thing to do that would not cause suffering to a typical person.
The reasons for this are
A) It would be too hard to do otherwise, to cater to every special need, in this case it is easy, but not in all cases, so this is no general principle.
B/1) It would not help the other person much, if the other person is unusually sensitive, the problem would not be fixed by one person catering to them. A hundred people should cater to it, after all there are many sources of noise in the neighborhood.
B/2) In other words, if you are unusually rude, reducing it to usual levels of rudeness is efficient, because by that one move you made a lot of people content. But if you are already on the usual levels of rudeness and an unusually sensitive person is still suffering, further reduction is less efficient because you are only one of the many sources of their suffering. And these people are few anyway.
C) Special needs are easy to fake.
D) People should really work on toughening up and growing a thicker skin, it is actually possible.
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