Among the many oblique fears that float in and out of daily consciousness – of crowds, phone calls and, in my case, vague elevator-dread – there is one, perhaps, that unites us: the fear of public nakedness. It’s something I thought about last week while standing in a communal changing room in midtown Manhattan.

I was at a sample sale, those feverish shopping events to which women dash in their lunch breaks on the promise of steep discounts, and for which they will pay a hefty price: that of jostling half-naked in front of the mirror, alongside someone trying on the same thing three sizes smaller.

The warehouse space was crammed with women from the skyscrapers around Penn Station. It was a mixed demographic: sales teams, secretaries, posh ladies who clearly weren’t going back to the office. (Even rich people don’t want to pay $180 for a pair of Tory Burch jeans when they could pay $60.) And they were all different shapes and sizes, but it turns out the universal anxiety of getting undressed in public was a strange and heartening leveler.

This is not normally my experience in a group of naked women. We are always told that part of the problem that feeds into assumptions about beauty is that not enough “real women” are visible in public life. And when they are visible, we are programmed to regard their “shortcomings” as critically as we regard our own.

For the brief period I was a member at a fancy gym, I remember how hostile the locker room was, a place of sidelong glances and constantly updated speed records for putting on your pants before someone came round the corner and pushed past you to their locker; where the buff strode about like naked Scandinavians and everyone else scuttled sideways like crabs. Gym culture, for all its slogans about fostering self-worth, is an environment second only to the fashion industry for stoking the very anxieties it claims to cure.

But something odd happened at the sale last week. The atmosphere in the group changing room was, although jittery, quite jolly. The spectacle of scores of women trying on the same five items was impossible to view as anything but comic, a visual gag that blew apart the lie of the ad-campaign: that there was only one way to look good in this item of clothing.

It was also, surprisingly, mutually supportive. OK, so the line “that looks great on you” won’t be etched into history as one of the lasting liberation slogans. But in its quiet way, the exchange of advice and encouragement, cheer-leading and help was a surprisingly touching experience for a random Thursday. Above all, it broke the seal on the isolation of city life. In this sea of strangers, where we increasingly go about in our own bubbles, shut off by headphones or in self-identified communities out of which we rarely venture, there is something to be said for being together in a shabby room, chasing bargains with nowhere to hide.

I was standing next to a French woman, who had managed to command one of the sales staff to run back and forth with new sizes for her, and to whom the woman at the neighboring mirror was acting in the role of Harriet Smith, loyal aide in Jane Austen’s Emma.

“You so have too good of a body for that,” she offered, when the French woman picked up a body-disguising kaftan, before the sales clerk came back and held up a top for her approval. “Is it size 6?” she asked. There was a pause, during which everyone in the room looked over and mentally supplied the answer: she likes it if it’s a size 6, and not if it’s an 8.

Then we turned back, regarding each other as human mirrors, in which, for a moment, there was no gap between the real and imaginary.