Logical Fallacies A logical fallacy is, roughly speaking, an error of reasoning. When someone adopts a position, or tries to persuade someone else to adopt a position, based on a bad piece of reasoning, they commit a fallacy
Bandwagon Fallacy committed by arguments that appeal to the growing popularity of an idea as a reason for accepting it as true. Or, Following an idea or organization because everyone else is doing it too.
Hasty Generalization draws a general rule from a single, perhaps atypical, case.
Examples: Black people are criminals Chinese people are intelligent Arabs are terrorists White people are racist Gay people are flamboyant
Ad Homenim or Personal Attack An argument based on the failings of an adversary rather than on the merits of the case
Bill: "I believe that abortion is morally wrong.” Dave: "Of course you would say that, you're a priest." Bill: "What about the arguments I gave to support my position?" Dave: "Those don't count. Like I said, you're a priest, so you have to say that abortion is wrong. Further, you are just a lackey to the Pope, so I can't believe what you say."
A prosecutor asks the judge to not admit the testimony of a burglar because burglars are not trustworthy. Prof. Smith says to Prof. White, "You are much too hard on your students," and Prof. White replies, "But certainly you are not the one to say so. Just last week I heard several of your students complaining."
Poisoning the Well in which a person attempts to place an opponent in a position from which he or she is unable to reply.
CITY COUNCILMAN: The Mayor's a very good talker. Yes, talk he can do... and do very well. But when it comes time for action, that's a different matter.
Non Sequitor A conclusion does not follow logically from what preceded it. A common way that this occurs is to take a specific truth and apply it in general terms to draw a conclusion that doesn't necessarily follow.
This war is righteous because we are French!' or 'You will do what I say because you are my wife!'" Ralph Wiggum: Martin Luther King had a dream. Dreams are where Elmo and Toy Story had a party and I was invited. Yay! My turn is over! Principal Skinner: One of your best, Ralphie. Terrorists attacked America. There are terrorists in Palestine. Therefore we should attack Palestine. Greenhouse gases are known to contribute to global warming. We (people) are producing greenhouse gases, therefore all of the global warming is caused by man and is bad
Slippery Slope A course of action is objected to on the grounds that once taken it will lead to additional actions until some undesirable consequence results.
"We have to stop the tuition increase! The next thing you know, they'll be charging $40,000 a semester!” "The US shouldn't get involved militarily in other countries. Once the government sends in a few troops, it will then send in thousands to die.” "You can never give anyone a break. If you do, they'll walk all over you.” "We've got to stop them from banning pornography. Once they start banning one form of literature, they will never stop. Next thing you know, they will be burning all the books!"