Home is different. If I practice karaoke songs in the shower or sing to my dog in my living room, yes, I run the risk of people overhearing me. But I would be mortified if anyone asked me to tone it down, because my neighbors and I have an unspoken agreement: I will tolerate your moderately loud music, your late-night gatherings, your TV laughs and your sex noises and your errant farts, and you will tolerate my own.

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Anyone who chooses to live in such close proximity to others knows how important it is to create boundaries and respect one another’s privacy. But sometimes the outside encroaches and our neighbors’ business becomes our own, whether we like it or not. Yes, voyeurism can be titillating, but what about unintentional voyeurism, when you’re happily minding your own business and a situation presents itself that you can’t ignore? Your neighbors’ yelling could be just a regular fight, or it could be something more dangerous; that distinction is hard to make when you’re hearing it through a wall.

You have a few choices, all of which have their own ambiguities and consequences. You can intervene directly, by knocking on the door and “just making sure everything is okay,” or even knocking and asking to borrow some sugar—anything to alert your neighbors that you’re there and witnessing their fight. If someone is in immediate danger, well, then you’d of course want to help. But what if no one is, and you’re just being a busybody? What if you make the situation worse? There’s also the natural fear almost anyone would feel walking into a potentially violent situation, perhaps not to save the day but to wind up hurt yourself.

You can call the police. But you run the risk of wasting their time and mortifying your neighbors. Even worse, you might possibly put your neighbors in danger if the police were to overreact and hurt them. You can also simply ignore the noise and hope it stops. But then there you are, just you in your home, not knowing when a fight is just a fight—another messy part of the social contract that neighbors learn to ignore as a part of life—and when it’s worse. Google neighbors fighting and you’ll find Reddit threads and advice columns full of people trying to decipher the line between ordinary disputes and domestic violence. When does it become my business?, we want to know.

Of course, the trouble is that there’s no way to know. In the early aughts, I lived on the Upper East Side in a one-bedroom apartment with a cardboard wall erected in the living room to create a tiny second bedroom for me. If my roommate was watching TV in the living room while I wanted to read, I’d close the little door to my room and get into bed, putting on headphones to avoid the ambient sound. Anything to drown out the proximity of this other person whom I had chosen to live with. Both of us would do anything to avoid a direct confrontation. But not the newly married couple down the hall who were clearly having a rough time. Every few nights or so we heard them yelling at each other, and one evening it sounded particularly bad. I could hear two distinct voices screaming at each other, and then a crash. More screaming. My roommate and I peeked out down the hall, wondering what to do.