I am an androgyne in real life. Some people who meet me wonder what sex I am; others are sure they know, but their certainties don't agree. I've met other androgynes, though not many. Some, like me, are androgynes thanks to a chance combination of traits; others achieve androgyny by a deliberate mixing of messages.

On the Net, you'd think there'd be a lot of androgynes. After all, the Net hides the physical cues by which others recognize our sex--voice pitch, body size, shape. It lets us present ourselves purely with words.

But there's nothing new about hiding the body. Clothes have been doing that since prehistory, albeit only partially. Yet most people use clothes to assert, not mask, their sex. On the Net, full names and home pages stand in for mascara and neckties as ways of extinguishing doubt. There are glitches, to be sure. Men named Stephane and women named Michael have trouble. But most find some way to resolve the ambiguity. One fellow I knew even put it in his signature: "PLEASE! In Russia, Misha is a man's name."

An ambiguous name or handle doesn't make you genderless, either. First of all, there are few names with no gender associations. Most people assume Pat is a woman and Chris a man. Call yourself Mink, and they'll be sure you're female--quite as if minks reproduced by parthenogenesis. Go by Wolf, and you must be male, there being no female wolves in the bestiaries of the urban mind.

Even if your name is truly ambiguous, people will rarely ask what sex you are. Instead, they'll assume a sex for you. Most often, they'll treat you as male until proven otherwise. That New Yorker cartoon got it only half right: True, on the Internet nobody knows you're a dog; the bad news is that everyone thinks you're a cat.

I used to frequent a network where most people used their full names. Once, though, a new bulletin board joined the network, bringing immigrants who went by initial and surname: lpeters, mjohnson, dsilva. No one thought to ask the newcomers what sex they were. Over the months, casual remarks revealed the truth, and many of us found out we had been wrong--not half the time, but nearly half.

I've seen this again and again. We cherish the belief that men and women communicate very differently, just as we insist that our favorite brand of beer or cola is nothing like the competitor's inferior brew. Yet when the labels are switched, we often can't tell the difference. A gender role is not a single icon, but a multitude: the manly man, the businessman, the nerd, the sissy. Somewhere in there is a stereotype to explain anything you might do. So if your communication style doesn't match the pop-psych code, people won't suspect you of being the other sex. They'll just shuffle you into a different sub- gender, and judge you accordingly.

So on the Net, cross-dressing--or rather, cross-naming--is easy. Learning to "pass" as the other sex at the nightclub or the grocery store can take years of work. On the Net, it's a bitflip. It's so easy that no one knows how common it may be.

But it's hard to remember that we don't always know each other's sexes on the Net. Some people, on some newsgroups, use gender-free pronouns like "sie" or "ey" for anyone who hasn't expressed a preference for "he" or "she." But most people go on acting as if gender were as clear online as we like to think it is offline.

The fantasy of leaving the body behind shapes many people's ideas about the Net. On the Net, say transhumanists, we leave our bodies behind; we transcend race and sex. And that bodilessness, Luddites claim, is dangerous; we need to turn off our computers and interact as human beings. But if we don't interact as human beings on the Net, then what, exactly, do we interact as? We are still apes on Usenet; we love and we hate--mostly, alas, the latter.

We drag our bodies along with us onto the Net; we're too corporeal to do anything else. We may like to think of ourselves as ethereal beings hovering in cyberspace, but we're more like Elmer Fudd walking off a cliff--so sure of our ground that we may never notice that nothing is holding us up.