Chapter 14: Argumentation Logical Fallacies

Begging the Question (Circular Reasoning) Asks the reader to accept the conclusion as true by offering a premise that has not yet been proven true. (Sometimes the premise is unstated.) Ed is obviously uneducated because he is a plumber. These movies are popular because they make so much money.

False Analogy Using an analogy to support arguments when the analogy goes a little too far. There are hidden assumptions that don’t stand the test of relevance. Medical Student: "No one objects to a physician looking up a difficult case in medical books. Why, then, shouldn't students taking a difficult examination be permitted to use their textbooks?"

Ad Hominem (Personal Attack) Refutes the opposition’s arguments by attacking the individual. Smear Technique His argument must be false because he swears and has bad breath.

Hasty Generalization (Jumping to a Conclusion) Drawing an inductive conclusion based too little evidence Most of the people in the room opposed the project, so most people in the town probably would oppose it too.

False Dilemma Forcing the audience to accept an either-or solution while ignoring other viable possibilities. Oversimplifies an issue and forces people to choose between two extremes. If you don’t go to college, you won’t be able to find a good job. You’re either with us or you’re against us.

Equivocation Occurs when a key term or phrase in an argument is used in an ambiguous way, with one meaning in one portion of the argument and then another meaning in another portion of the argument. Noisy children are a real headache. Two aspirin will make a headache go away. Therefore, two aspirin will make noisy children go away.

Red Herring An irrelevant issue is introduced into a discussion to draw attention away from the central issue. I work sixty hours a week to support my family, and I pay my taxes. You can’t give me a parking ticket!

You Also (Tu Quoque) Refuting argument because the campaigner is guilty of the same offense he’s campaigning against. Drug addict persuading us not to use drugs. “How can the police ticket me for speeding? I see cops speeding all the time.”

Appeal to Doubtful Authority Relying on opinions from an expert in one field about a topic in another field. A popular football player discusses the benefits of aloe in a shaving cream advertisement.

Post Hoc, Ergo Propter Hoc (After this, therefore because of this) Claiming that because one event occurred before the other, the first must have caused the second. Eating five candy bars and drinking two sodas before a test helps me get better grades. I did that and got an “A” on my last test.

Non Sequitur (It Does Not Follow) A statement does not follow logically from a previous statement. The rain came down so hard that Jennifer actually called me.

Bandwagon Effect (Ad Populum) Emotional appeals to secure agreement by implying that a position must be accepted regardless of the evidence because… Everyone with credibility holds that position. Why can’t I get a tattoo? Everyone else has a tattoo.

Slippery Slope A course of action is rejected because, with little or no evidence, one insists that it will lead to a chain reaction resulting in an undesirable end or ends. If we legalize pot, then that will lead to every drug in the world becoming legal. We have to stop them from banning alcohol. Pretty soon, they will be banning soft drinks too.

Additional Information Fallacies overlap: Be like Mike an ad by Nike Air Jordan Shoes = fallacious appeal to authority and a subtle bandwagon appeal. Fallacies are often subtle. Identify the conclusion that you are being asked to accept and question how the author arrived at that conclusion. Arguments containing fallacies are sometimes very persuasive.