Presentation on theme: "Critical Thinking: Chapter 7 More Fallacies. The Ad Hominem Fallacy The ad hominem fallacy rests on a confusion between the qualities of the person making."— Presentation transcript:
Critical Thinking: Chapter 7 More Fallacies
The Ad Hominem Fallacy The ad hominem fallacy rests on a confusion between the qualities of the person making a claim and the qualities of the claim itself. It is a rhetorical device that attacks the arguer instead of the argument.
The Ad Hominem Fallacy A proposal made by an oddball is an oddball’s proposal, but it does not follow that it is an oddball proposal.
Personal Attack Ad Hominem A pattern of fallacious reasoning in which we refuse to accept another’s argument because there is something about the person we don’t like or of which we disapprove.
Personal Attack Ad Hominem Example: Are you really going to believe her about librarians’ salaries not being excessive? I’ll have you know she herself is a librarian, or don’t you think that matters?
The Inconsistency Ad Hominem A pattern of fallacious reasoning of the sort, “I reject your claim because you act inconsistently with it yourself,” or “You can’t make that claim now because you have in the past rejected it.”
The Inconsistency Ad Hominem The double standard argument is actually the inconsistency ad hominem.
The Inconsistency Ad Hominem Example: Did you ever notice how the people who favor abortion on demand are the same people who are against the death penalty?
The Inconsistency Ad Hominem Example: It really gripes me to see Bill Clinton talking about how cigarette smoking is a big contributor to public health costs. How can we trust him? Even he himself admits to smoking cigars!
Circumstantial Ad Hominem Attempting to discredit a person’s claim by referring to the person’s circumstances.
Circumstantial Ad Hominem Example: Of course the Task Force on Crime is going to conclude that crime is on the way up. If they conclude it’s on the way down, they’d have to disband the task force, wouldn’t they?
Circumstantial Ad Hominem Example: Of course that can’t be a legitimate proposal. They’re just trying to get the city council to pass a regulation that will stir up some business for them.
Poisoning the Well Poisoning the well can be thought of as an ad hominem in advance.
Poisoning the Well Example: I wouldn’t take a course from anyone in the Poly Sci department, if I were you. They are all anti-U.S., ultraliberal types, at least that’s what I hear.
Poisoning the Well Example:The next speaker is going to speak in favor of the idea. But she works for the gun lobby Don’t even bother listening to what she says.
Genetic Fallacy The genetic fallacy occurs when we try to refute a claim on the basis of its origin or history. Rejecting a proposition because it is supported by a group you don’t like is a genetic fallacy.
Genetic Fallacy Example: You can’t trust the arguments you find in that magazine. It’s well known as a right-wing apologist for the wealthy.
Genetic Fallacy Example: I don’t think postmodern expressionism is decent art. It’s another style spawned by the East Coast art establishment, and, frankly, I’m tired of that group’s dictating to the rest of the art world.
Positive Ad Hominem Fallacies If we automatically transfer the positive or favorable attributes of a person to what he or she says, that is a mistake in reasoning, as well.
Positive Ad Hominem Fallacies Example: The fact that in your view the NRA represents all that is good and proper does not enable you to infer that any specific proposal from the NRA is good and proper.
Positive Ad Hominem Fallacies Example: The fact that you think your mom is clever does not logically entitle you to conclude that any specific opinion of your mom’s is clever.
The Straw Man Fallacy The straw man fallacy happens when you refute a position or claim by distorting or oversimplifying or misrepresenting it, all the while ignoring the person’s actual position.
The Straw Man Fallacy Example: Gays in the military? Yes. Maybe you favor excluding everyone except for white Anglo-Saxon males with adolescent personalities, but not me.
The Straw Man Fallacy Example: Do I want the police department to take charge of writing parking tickets? You mean, do I want to get shot if I pull up next to a fire hydrant? What do you think?
The False Dilemma Fallacy The false dilemma fallacy occurs when you limit considerations to only two alternatives although other alternatives may be available. A straw man is often used as part of a false dilemma.
The False Dilemma Fallacy Example: Overheard: “I don’t know why Barbara won’t go out with me. She must think I’m too intense for her.”
The False Dilemma Fallacy Example: Gays in the military? Either let them in, or keep out all minorities; take your choice. I’m for letting them in. the alternative is ridiculous.
The Perfectionist Fallacy The perfectionist fallacy is a subspecies of false dilemma and a common rhetorical ploy. This principle downgrades policy X simply because it isn’t perfect.
The Perfectionist Fallacy Example: No, I don’t believe we ought to reinstate the death penalty in this state. Doing it isn’t going to prevent all crime, and you know it.
The Perfectionist Fallacy Example:Don’t stay in the army. You were ROTC instead of going to one of the academies, and that means they might promote you for a while, but you’ll never get above lieutenant colonel.
The Line-Drawing Fallacy Another version of the false dilemma is called the line- drawing fallacy, the fallacy of insisting that a line must be drawn at some point when in fact it is not necessary that such a line be drawn.
The Line-Drawing Fallacy Example: All this talk about secondhand smoke causing cancer, I just don’t get it. How does it happen? WHEN does it happen? The first time you take a breath in a smoky room? The second time? You can never pin it down exactly.
The Line-Drawing Fallacy Example:What do you mean, I broke my curfew? All I did was walk to the curb. You wouldn’t cite me if I stood on the porch, would you? And if I’d just stepped off the porch, that wouldn’t be any different. So what’s so magical about the curb?
Slippery Slope A form of fallacious reasoning in which it is assumed that some event must inevitably follow from some other, but in which no argument is made for the inevitability.
Slippery Slope Example: No, I don’t believe in “three strikes and you’re out” for convicted felons. Next thing it will be two strikes, then one strike. Then we will be sticking people in jail for life for misdemeanors. It’s not good policy.
Slippery Slope Example:Gays in the military? If we allow that, then next time we’ll be letting women into the men’s barracks. And the next thing you know, women, men, gays, everyone--they’ll all be showering together and sleeping in the same bunks. Get real.
Misplacing the Burden of Proof Misplacing the burden of proof occurs when the burden of proof is placed on the wrong side of an issue.
Misplacing the Burden of Proof 1. The less initial plausibility a claim has, the greater the burden of proof we place on someone who asserts that claim.
Misplacing the Burden of Proof 2. Other things being equal, the burden of proof falls automatically on those supporting the affirmative side of an issue rather than on those supporting the negative side.
Misplacing the Burden of Proof When someone claims that we should believe in such-and- such because nobody has proved it isn’t so, we have a subtype known as appeal to ignorance.
Misplacing the Burden of Proof 3. Special circumstances like court or contracts will specify where the burden of proof lies so there are no doubts or confusion about who needs to prove what.
Misplacing the Burden of Proof Example: I beg to differ, Officer, but sometimes you people go overboard talking about the dangers of fast driving. If you can prove that there’s actually a child near the street right now, and that the child would have stepped out in front of my car, then I’ll grant you that going fifty-five was dangerous.
Misplacing the Burden of Proof Example: Preferential treatment in hiring is something we must support; after all, can you think of a reason why we shouldn’t?
Begging the Question We are guilty of begging the question when we ask our audience to accept premises that are as controversial as the conclusion we’re arguing for and are controversial on the same grounds.
Begging the Question Example: The ACLU? Yeah, I know about them, and I don’t like them very much. They’re the ones who furnish free lawyers for criminals.
Begging the Question Example: No, I don NOT believe that a murderer ought to be allowed to live. No way! Murderers have forfeited the right to live because anyone who murders another person has lost that right.