If you're reading this, you probably don't need convincing that there exists a thing we can call Net ethics. That's because most of us get our sense of right and wrong first at home, then from figuring what we'd like to have people think we do. In the real world that's pretty much how you get the gist of these things: monkey see, monkey do, monkey do the right thing. From this you get, if we're lucky and you weren't raised by wolves, ethics.

You also don't have to be a paragon of ethics yourself to be able to talk about them, which is where I come in. I've been online nearly 15 years, and you may trust that a good portion of that was spent as a bad example. (But let's leave my MP3 collection out of this for now.) You do have to be willing to throw yourself headfirst into thinking about why we do the things we do and how we can, as a venerable ethics-column predecessor of mine put it, "live right in an amoral world."

Let's get to work. A friend writes:

Is it wrong to pretend to be someone else online? -- Free to Be... He and She

We've all heard that bromide that goes something like, "On the Internet, no one knows you're a dog." Chances are, though, that folks will know if you're a rat. A lot depends on why you're changing your identity.

For instance, back in the bad old days of my chatroom habit (I'm much better now, thanks), I'd seek out the AOL chat with the biggest, most obnoxious troll in existence and pretend to be exactly the kind of person who would yank that person's chain hardest. It was a way of expending the mind-clearing adrenaline of a bar fight without the nuisance of an actual police record. Spending 30 minutes here as a lesbian mom in a long-term partnership, 45 minutes there as a farmer arguing about crop subsidies, was something I did to annoy people who were annoying other people. I thought of myself as a kind of Digital Avenger, shouting down jerks.

What I didn't count on was the positive responses of the people I thought I was defending. They liked the person I was pretending to be and wanted to talk with that person outside of the conflict. But "that person" was a lie. In getting myself out of those situations, I had to admit to some people that I'd betrayed their trust. Some avenger.

That's what you'd call a sin of commission: I actively claimed to be something I'm not. On the other hand, sins of omission are a lot less problematic. Say you and I are discussing what we did in college, and you mention that you saw the movie Titanic when you were a frosh.

From that statement I might assume you to be about 20 years old. But perhaps you're a nontraditional student and are actually 50. Unless the topic comes up, you don't "owe" me that data. I assumed, I was wrong, my bad. The only place sins of omission are significant is when participating in groups restricted to a characteristic you don't have: women-only discussions, perhaps, or under-18 chats.

That's dogs for you; now a word about the rats. A lot of online communities are familiar with serial trolls: people who enter a community, start kicking up trouble, get kicked out or shunned, and reenter the community under a new name.

There are lots of reasons someone will attempt reentry, some good (a chance to redeem oneself) and some bad (a few last grenades to throw). I propose a deal with these people: If the rest of us agree that sometimes folks deserve a second chance, will you agree to be honest if someone asks you, "Hey, weren't you so-and-so before?" Lying is just an embarrassment in these situations. Take your chances and prove you're worth not zapping this time.

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