Think very carefully before you challenge a conspiracy theorist to a public debate. Some of the points to ponder include:
  • publicity is the "jet fuel" of the conspiracy theory business. If you can deprive them of an audience then you're probably doing more good than you can ever hope to achieve during a debate (even if you win).

  • remember that the conspiracy theorist can "win" simply by making sure that she/he doesn't lose the debate badly. In order for you to "win", you have to defeat your opponent TOTALLY.

  • if you defeat your opponent TOTALLY then you run the risk of your opponent winning the "sympathy vote" (i.e. even if you win, you might still lose).

  • any good conspiracy theorist knows all the tricks of the trade including:

    • asking questions that don't have "sound bite" answers
    • ignoring the question if they don't like it and "answering" some other unasked question
    • providing "sound bite" almost-answers to questions that don't have "sound bite" answers
    • looking at you like you're "one of them" or "a fool to believe that"
    • playing to the audience's emotions
    • knowing where there are likely to be holes in the audience's knowledge and filling the holes in with "perfect" lies
    • disagreeing with absolutely everything you say (remember - they only need to "not lose badly" and you need to "win TOTALLY")

    (this is NOT a complete list)

  • the conspiracy theorist doesn't really care about what you have to say. After all, they're main goal in being there is to get publicity (already done if you're having a public debate) and attract more devotees.

  • agreeing to debate a conspiracy theorist gives them instant credibility as it essentially proves that you think that their theory is worth debating (i.e. they have identified a legitimate point of dispute). See below for more on this point.

  • agreeing to debate a point which is not a legitimate point of dispute hurts your credibility beyond the realm of the debate (i.e. it suggests that you have poor judgement).

  • losing or appearing to lose (they are the same thing) a debate over a point that isn't worthy of debate reflects quite badly on you and could be used by the conspiracy theorist as proof or at least evidence that they are right. In contrast, if you win then the conspiracy theorist will simply ignore the event.

  • Be very careful and aware of the subtleties of the "freedom of speech" right (the exact nuances of the "free speech" right vary from country to country). While it is true that everyone has a right to speak their opinions, nobody has a right to have their opinions heard by your audience! Unless you are denying someone the right to speak at all, refusing to provide someone with an opportunity to speak via your forum, web site, radio station, newspaper, etc. is not denying someone their "freedom of speech" rights. After all, they are free to find or build a forum, web site, radio station, newspaper, etc. that will carry their views. You are denying them their right to speak if you actively interfere with them when they are trying to speak (hecklers who try to disrupt someone speaking are denying the speaker the very right that they themselves are claiming gives them the right to heckle!).

  • Watch out for the "there's another side to every story" tactic. This notion has all sorts of problems:

    • there is no other side to the truth! i.e. there might be another side to every opinion but a fact is either true or false. There are facts which we can't judge the truth of - e.g. "intelligent life exists on other planets" but the statement is either true or false (it is usually a waste of time to debate facts which can't be decided).
    • don't confuse the difference between opinion and belief or the difference between what you know and what you believe (a certainty of belief isn't the same thing as a knowledge of fact, no matter how strongly the conspiracy theorist might wish or believe that they were the same).
    • don't be afraid to know things (although it won't do you any good when debating a conspiracy theorist). For example, I know that the Earth orbits the Sun just like I know that the Holocaust happened (see below).
    • don't be afraid to make assumptions and treat them as facts that you know as long as, at some level, you realize that they are actually assumptions and not facts. For example, I know that my truck is parked outside. I might be wrong (trucks do get stolen from time to time) but I can't go through life worrying about every uncertainty so I know that my truck is parked outside.
    • understand the difference between reasonable doubt and unreasonable doubt. It isn't necessary to be presented with absolute proof of something before you're allowed to know that it is true. Reasonable doubt is exactly that - "reasonable".
    • you aren't obligated to give someone an opportunity to change your mind about anything and you definitely don't need to give someone an opportunity to brow beat you into agreeing with them!
    • while it is possible that President Kennedy was shot by a rogue CIA assassin, that doesn't mean that he was shot by a rogue CIA assassin. He might be still alive or he might have been killed by a death ray from Mars! The mere fact that a tiny bit of doubt exists doesn't make the question of whether or not President Kennedy was killed by a rogue CIA assassin a legitimate point of dispute.

    Although many topics of conspiracy theories might be subject to debate, a lot of conspiracy theories try to turn established facts (or falsehoods) into points of legitimate dispute.

    An example might be in order here: suppose that someone were to claim that Napoleon didn't invade Russia or that George Washington wasn't the first U.S. President. Does the existence of such an absurd claim mean that whether or not Napoleon invaded Russia or whether or not George Washington was the first U.S. President is now a question worth investigating? Don't confuse the legitimate desire to read things for yourself or to get to the bottom of things (e.g. was George Washington ever the President under the current U.S. Constitution?) with some sort of bogus obligation to prove to someone that they are wrong!

  • Watch out for false or irrelevant controversies. This is a favourite tactic of "the Holocaust never happened" conspiracy theorists. Even though there is no doubt that the Holocaust happened (i.e. that it was a campaign of organized government sanctioned murder on an industrial scale that killed millions of people), there are areas of legitimate controversy. For example, "how many Jews were murdered (to the nearest million)?" and "how widespread was the knowledge of what was going on". The first question, "how many were murdered?", is used to cast doubt on whether or not more than a handful were murdered (as a bare minimum, at least a few million were murdered). The second ("how widespread was the knowledge?") is used in all sorts of creative ways although the worst is to suggest that Hitler wasn't "in the loop" - there is absolutely no rational reason to doubt that Hitler was behind and supported the Holocaust. Just read his book Mein Kampf if you have any doubt on where he stood or read Rise and Fall of the Third Reich or any other good history of the war if you have any illusions about how "in the loop" he might have been!

Check with a lawyer in your jurisdiction before you take my comments about free speech rights too seriously as you could land in legal trouble if you deprive someone of their rights.