You've heard fallacies before. They're the kind of thing that tend to end a debate, not because they're great, but because they're not supported by facts and arguments. They tend to bring a debate into an endless and unproductive loop.
Students of rhetoric have examined these false arguments for centuries, and there's a long list of rhetorical fallacies and how to combat them.
Below are some of the more common fallacies to avoid when you're trying to persuade an audience -- typically in a speech, oped or a public debate.
It's also useful to study fallacies so you know how to combat them when you see the opposition using them against you.
Argument from authority -- "Because I'm your mother" is simplest example of this fallacy. You'll see others fall back on this argument, asking people to do what they say or believe what they're saying simply because they occupy a place of authority or fame, whether they're a Hollywood actor or a U.S. senator.
Straw man -- "Some politicians say we should let people define marriage however they want -- marry two women, marry your dog, whatever. I disagree." This fallacy sets up a false argument that nobody is seriously proposing just to knock it down.
Argument from force -- "Do it or I'll hit you with this rock." The speaker tries to get an audience to comply through the threat of force. It's usually not as explicit as the business with a rock.
Ad hominem attacks -- "Buy a car from me, because the Ford dealer down the street is an idiot and a liar." This fallacy is a personal attack on the opponent, ignoring the merits of the real debate or issue.
False choice -- "You're either with us, or against us." This fallacy oversimplifies a complicated situation and turns it into a false either-or choice. Another example: "If you really loved me, you'd ..."
Slippery slope -- "If you let Congress ban bazookas and machine guns, next they'll be coming door-to-door to grab your hunting rifles and handguns." This fallacy equates a small step with outlandish and unlikely harms.