Here's an example of Troll's strategy: you take a sensitive topic (like the ban on minarets or the latest problem with Macintosh OS), and you build an argument around it. The conclusion of your argument is blatantly absurd, but every premise is correct, except one. The trick is to hide that wrong premise under an intricate discussion. You know that people will be so hasty to resist your conclusion that they will start by attacking the true premises. You have prepared a violent rebuttal for each objection, and you know that, since you are right on those points, some objective debaters might side with you, which will divide the discussion group (a crucial step). You hope that the discussion of your true premises will become so heated that, when someone finally notices the flaw in your argument, people will be too busy insulting you to care about that. This is the kind of cold-blooded, cunning, premeditated strategy that only genuine Trolls can devise.

We can find Trolls in some of the first public places where free conversation between strangers was allowed, on a variety of topics : the antique Forum, grandfather of the virtual forums of today, womb of all Trolls. There you may find the antique equivalent of Trolls : what people at the time called 'sophists' or 'philosophers' - two words that were used interchangeably by the man on the Forum. Many Sophists did not want to endorse the label - sophistry was frowned upon or downright illegal in many places - and insisted on being called Philosophers. But the average citizen did not distinguish much between all these varieties of arguers. It is clear from most outsiders' accounts that sophists/philosophers were perceived as disrupting the usual rules of conversation in a noxious way.

Two important men are having a careful conversation on military training. What do you call the guy who, having no particular competence or interest in the matter at hand, jumps in the conversation, systematically contradicts everyone with contrived arguments, ridicules the two competent discussants, orients the conversation on a completely different topic, then leaves the audience baffled and walks away, laughing? That Troll is Socrates in Plato's Laches. True, Plato's Socrates seldom hops in uninvited, and most of his interlocutors do not consider him noxious. Indeed one wonders why the whole city grew so irritated that they voted to condemn him to death. But Plato, like all philosophers and sophists, had a stake in defending his colleagues. In other views of Socrates (like Aristophanes' caricature), he is unmistakably trollish.

And Socrates was not your average philosopher or sophist. His colleagues' methods were much cruder. Take Diogenes, a hobo who combined unsollicited moral counselling with aggressive begging. Take travelling philosopher Stilpo, who, each time he entered a town, went on the forum, jumped on a soapbox, brandished an onion and claimed he could prove it was not a vegetable (Proof: a vegetable existed 100 years ago. This vegetable did not exist 100 years ago. Therefore, this is not a vegetable), then rebutted all contradictors and baffled the audience till the town went mad at him. There were hundreds of Stilpos at a time, in all parts of the world where annoying intellectuals were tolerated. The Chinese had their Trolls too, whose discussions would create Chinese Logic. And of course, just like Trolls, these early philosophers tended to make themselves quite unpopular in several places. There is a reason why Athens punished sophistry with banishment, or worse.

Conversation hackers are useful. Like other hackers, they test the boundaries of a system, and they force users to devise better systems. They strain human argumentation to its limits. Dealing with Trolls forces you to sharpen your arguments and keep a cool head. Sometimes you might even learn something from a Troll. Socrates was maddening, but he helped make some concepts clearer. And all these Greek and Chinese philosophers/sophists forced their interlocutors to revise the usual rules of argumentation and make them much more specific. Some modern logic was born from these efforts. As usual, a system's hacker is often the best expert in the security of that system.