Faulty Logic

• Lying: Saying things which you know to be untrue.

• Telling only part of the truth: Leaving out information which you know would help the audience to make up its mind.

• Taking the truth out of context: Such as movie ads, which announce that the New York Times critic said "...amazing..." but don't tell you that the actual quote from the review was "It's amazing to me that anyone would waste $8 on a ticket to see this garbage."

 

• False Cause: The argument that, since events happened in AB order, event A must have caused event B. Also known as superstition. (I wore my red sweater. I did well on my speech. Therefore, my red sweater must be lucky!)

• False Dichotomy: Presenting a limited range of alternatives as if it were comprehensive. ("Either follow the rehearsal program in class or you'll mess up your speech!" This argument ignores the possibility that you might be talented enough to do well on your speech without rehearsal, as well as the possibility that you might follow the rehearsal program and yet mess up your speech anyway.)

• False Testimonial: The argument that, because there's something good about X, everything about X must be good. (Michael Jordan is a great basketball player. Therefore, his opinion about hotdogs must be worth listening to!)

 

• The Argumentum ad Hominem: The argument that, because there's something bad about X, everything about X must be bad. (Biff Clanton cheated on his wife with an intern. Therefore, he must be a terrible CEO.)

• The Bandwagon Effect: The argument that popularity equals quality. ("Aw, mom, all the kids have the X Box! It must be great!")

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