I was, signiFIcantly, driving while listening to an NPR call-in show about the monorail. I was only listening with half an ear because I was, also significantly, looking for parking. But I snapped to attention when someone called in to express his concern that the monorail would bring people to his neighborhood--Ballard--who didn't "fit in."

This was on some level surprising, but I was more surprised that the show's host and pro-monorail guest (I don't remember who it was) treated it like a real question. He cited studies that showed that most people who would go to Ballard would be drawn by the shops and the bars and the restaurants, but then did a little politically correct backpedaling and said, "I'm not sure I understand what you mean by your question."

I understood exactly what this jackass caller meant. He meant minorities, homeless people, people selfishly grabbing up Ballard jobs. This is what anti-monorail proponents call "social intrusion," one of the supposed "consequences" of building the monorail. The more I thought about the call, the more asinine it seemed to me. A city is a place where you are always bumping up against people unlike you, and that's part of its beauty. It's the social diversity we're always paying lip service to, without thinking about what it really means; people who gush about New York being "exciting" are, in some measure, invoking a quality of danger, of living near people whose circumstances are so different from their own. There are places for people who only want to be surrounded by other people who "fit in." They're called gated communities, country clubs, Idaho, and North Dakota.

To be born into New York's Upper East Side is to be born into a system of well-meaning constraints, not the least of which is a distorted view of how the city works. This provincialism can of course be due to snobbishness, to class entitlement, but it can also, as it was in my case, have more to do with protective parents. Here is a neighborhood where everything is in walking distance--school, allergy doctor, piano lessons--and deemed safe even for eight-year-olds to pilot themselves about alone. My best friend lived 20 blocks away, and I was on hailing terms with every doorman between my house and hers.

The skewed view of life outside the Upper East Side takes its most drastic form in the judgment of distance. My aunt in Gramercy Park was a cab ride. The dentist, midtown, was a bus. For trips really far away--say, Macy's in Herald Square, or to pick up my brother at nursery school at Riverside Church--we got the car out of the garage. Until I was about 12, a trip to Connecticut and a trip to the Upper West Side seemed roughly the same distance.

What happened when I was 12 was that I discovered the subway. It was a weekend near the end of the school year, and I was supposed to be studying at a friend's house, but my little group of us provincial private-school girls decided to hop on the 6 train and head downtown instead. At the corner of 86th and Lexington, we descended into the active heat of the station, where the thunder of passing trains and high shriek of bald brakes created oily sounds we could very nearly taste.

And my first revelation was that in a matter of nine quick stops, we were there, a block away from the famous Astor Place Hair. There was Washington Square, filled with interesting loitering people; there was Eighth Street, all lined with cheap shoe stores and head shops. There was Greenwich Village, a neighborhood where people with Mohawks, with aggressively and deliberately ripped clothing, with pins through their lips (it was the early '80s; this all still had the sting of originality to it), were as unsurprising as bottle-blond society ladies were in mine.

I don't want to turn this into a story of a privileged child having her first brief taste of the underground that would later consume her, although that wouldn't be untrue. The point is that the subway liberated me in a way that I wouldn't have been liberated otherwise. It's true, I think, that the city child enjoys a freedom that the suburban child doesn't: You measure your growing freedom by how far you're allowed to walk away from home unaccompanied, how many streets you're allowed to cross, and those increments take you to actual places rather than cul-de-sacs. The subway gave me something I wouldn't have had without a driver's license, or without having to catch a slow bus that rarely came (slow buses are a disincentive to actually go anywhere, which is why so few careless people "intrude" on Ballard). After only my first trip on the subway, it was clear to me that getting around the city was No Big Deal. And with this revelation came the more important one, which was that there were other ways to live.

Any New Yorker can tell you his or her history in subway stops. For me, Astor Place still has a certain resonance, as does the way Astor-Bleecker-Spring flies by when you're headed farther downtown. I can tell you about how the Union Square station is the worst--the trains never seem to come--and about the moment heading toward Washington Heights on the 1/9 train when you briefly burst into daylight. About the stretch between the Lexington Avenue line and the shuttle to the Broadway line at 42nd Street that I called "the Rapeway" because it was always so dirty and dangerous-seeming (and was applauded for my cleverness, but really I stole it from Wilton Barnhardt).

I found that the Upper West Side was actually not very far away. I found myself in neighborhoods that scared me (and let me tell you, Ballard Jackass, it's a good thing to spend time in places where you're not comfortable; it gives you humility). I went to the neighborhoods where my parents grew up (Sunnyside in Queens; Mosholu in the Bronx). I went to Arthur Avenue in the Bronx--more Italian than Little Italy--and Williamsburg and Greenpoint and Brooklyn Heights, where Walt Whitman lived. I went places that allowed me to look back at New York, to see and begin to understand the place I lived.

When I returned to New York for graduate school after a lengthy time in Seattle (where lack of rapid transit planted me firmly and unhappily in a car), I was able to get from graduate school on the Upper West Side to a job in SoHo to an apartment in South Park Slope in Brooklyn, all without undue strain--more or less the equivalent (in perceived distance and hassle) of going from Ballard to Georgetown to West Seattle, and back again. In New York there are few places that are truly too far away or not worth the bother, and the result is that more is available: more jobs, more culture, more life. I had forgotten this during six years in Seattle; it seemed like a fucking miracle.