1. FAULTY CAUSE: (post hoc ergo propter hoc) mistakes correlation or association for causation, by assuming that because one thing follows another it was caused by the other.
example: A black cat crossed Babbs’ path yesterday and, sure enough, she was involved in an automobile accident later that same afternoon.
example: The introduction of sex education courses at the high school level has resulted in increased promiscuity among teens. A recent study revealed that the number of reported cases of STDs (sexually transmitted diseases) was significantly higher for high schools that offered courses in sex education than for high schools that did not.
2. SWEEPING GENERALIZATION: (dicto simpliciter) assumes that what is true of the whole will also be true of the part, or that what is true in most instances will be true in all instances.
example: Muffin must be rich or have rich parents, because she belongs to ZXQ, and ZXQ is the richest sorority on campus.
example: I’d like to hire you, but you’re an ex-felon and statistics show that 80% of ex-felons recidivate.
3. HASTY GENERALIZATION: bases an inference on too small a sample, or on an unrepresentative sample. Often, a single example or instance is used as the basis for a broader generalization.
example: All of those movie stars are really rude. I asked Kevin Costner for his autograph in a restaurant in Westwood the other evening, and he told me to get lost.
example: Pit Bulls are actually gentle, sweet dogs. My next door neighbor has one and his dog loves to romp and play with all the kids in the neighborhood!