On a crowded 6 train I become aware of a tense exchange of words somewhere behind me. The dispute, as far as I can tell from what’s being said (and a quick glimpse at the next station confirms this) is between a middle-aged man and a young woman. The woman is seated, and it’s her nasal, strident tone that first draws attention: ‘Don’t you fucking touch me!’ she yells. He denies having done so. Her tone is accusatory, his is defensive; then, with each iteration, more defiant. The dispute seems to revolve around whether – and in what manner – he touched her when she sat down. Both parties, it seems, have entered into a zero-sum game, where accusation is pitted against denial, and neither can afford to give an inch. ‘If I’d touched you you’d know it!’ the man asserts. ‘You know you did, you fucking touched me!’ the woman retorts. She tells him to stop looking at her, he replies that he has no desire to look at her – why would he? People surrounding this feuding pair have shifted into subway tunnel vision: despite the fact that this dispute centers on uncomfortable personal-space issues common to all riders, no one is willing to jump into the fray of this one.