Ad hominem or ATTACKING THE PERSON. Attacking the arguer rather than his/her argument. Example: John's objections to capital punishment carry no weight since he is a convicted felon. Note: Saying something negative about someone is not automatically ad hominem. If a person (politician for example) is the issue, then it is not a fallacy to criticize him/her.
Ad ignorantium or APPEAL TO IGNORANCE. Arguing on the basis of what is not known and cannot be proven. (Sometimes called the “burden of proof” fallacy). If you can't prove that something is true then it must be false (and vice versa). Example: You can't prove there isn't a Loch Ness Monster, so there must be one.
Ad verecundiam or APPEAL TO AUTHORITY. This fallacy tries to convince the listener by appealing to the reputation of a famous or respected person. Oftentimes it is an authority in one field who is speaking out of his or her field of expertise. Example: Sports stars selling cars or hamburgers. Or, the actor on a TV commercial that says, "I'm not a doctor, but I play one on TV."
AFFIRMING THE CONSEQUENT. An invalid form of the conditional argument. In this case, the second premise affirms the consequent of the first premise and the conclusion affirms the antecedent. Example: If he wants to get that job, then he must know Spanish. He knows Spanish, so the job is his.
AMPHIBOLY. A fallacy of syntactical ambiguity where the position of words in a sentence or the juxtaposition of two sentences conveys a mistaken idea. This fallacy is like equivocation except that the ambiguity does not result from a shift in meaning of a single word or phrase, but is created by word placement.. Example: Jim said he saw Jenny walk her dog through the window. Ow! She should be reported for animal abuse.
APPEAL TO EMOTION. In this fallacy, the arguer uses emotional appeals rather than logical reasons to persuade the listener. The fallacy can appeal to various emotions including pride, pity, fear, hate, vanity, or sympathy. Generally, the issue is oversimplified to the advantage of the arguer. Example: In 1972, there was a widely-printed advertisement printed by the Foulke Fur Co., which was in reaction to the frequent protests against the killing of Alaskan seals for the making of fancy furs. According to the advertisement, clubbing the seals was one of the great conservation stories of our history, a mere exercise in wildlife management, because "biologists believe a healthier colony is a controlled colony."
ARGUMENT FROM ANALOGY or FALSE ANALOGY. An unsound form of inductive argument in which an argument relies heavily on a weak analogy to prove its point. Example: This must be a great car, for, like the finest watches in the world, it was made in Switzerland.
BEGGING THE QUESTION. An argument in which the conclusion is implied or already assumed in the premises. Also said to be a circular argument. Example: Of course the Bible is the word of God. Why? Because God says so in the Bible.
SLIPPERY SLOPE. A line of reasoning that argues against taking a step because it assumes that if you take the first step, you will inevitably follow through to the last. This fallacy uses the valid form of hypothetical syllogism, but uses guesswork for the premises. Example: We can't allow students any voice in decision making on campus; if we do, it won't be long before they are in total control.
COMMON BELIEF (Sometimes called the “bandwagon” fallacy or ‘appeal to popularity”). This fallacy is committed when we assert a statement to be true on the evidence that many other people allegedly believe it. Being widely believed is not proof or evidence of the truth. Example: Of course Nixon was guilty in Watergate. Everybody knows that.
PAST BELIEF. A form of the COMMON BELIEF fallacy. The same error in reasoning is committed except the claim is for belief or support in the past. Example: We all know women should obey their husbands....