Four blank walls capture nothing except the screams of people too broken to be let into the world. The reason they are blank is not because violent words splatter them constantly, almost as constantly as blood does. It's because if that happens they're all washed clean by the next morning, by a man in a janitor's uniform whose lips are always turned down in a frown.
Four blank, brick walls that capture nothing will never ever, stay nothing. They are loud to one beholder, quiet to another. Eerie to a young child with wide eyes, complacent to a three-time offender. But still, they wait blankly, until they are yet again covered with the misgivings and misfortunes of another empty shell of a person.