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MLS 570 Critical Thinking Reading Notes for Fogelin: PowerPoint Presentation
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MLS 570 Critical Thinking Reading Notes for Fogelin:

MLS 570 Critical Thinking Reading Notes for Fogelin:

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MLS 570 Critical Thinking Reading Notes for Fogelin:

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  1. MLS 570Critical ThinkingReading Notes for Fogelin: Fallacies of Clarity & Relevance Fall Term 2006 North Central College

  2. FALLACIES OF CLARITY • A fallacy is a type of bad reasoning that gets repeated so much that it gets its own name. • A lack of clarity can be just unclear thinking, or it can be done intentionally, often to confuse people. • Fallacies of Clarity • Heaps • Slippery Slopes • Conceptual Slippery Slopes • Fairness Slippery Slopes • Causal Slippery Slopes • Ambiguity • Equivocation

  3. Heaps A “Heap” is one form of arguing that depends on a lack of clarity by exploiting the existence of borderline cases to reach a not easy to disprove false conclusion. • In the example in the book the argument from the heap goes from showing that a person with one cent isn’t rich [we’d agree!] to saying that a person with only 100,000,000 cents is not rich. • The whole argument looks like:1- Someone with only one cent is not rich2- For any number n, if someone with only n cents isnot rich, then someone with n + 1 cents is not rich.3- someone with any number of cents is not rich.

  4. Where do heaps go wrong? • Change occurs over time and people do cease to be fat or poor if they lose enough weight or get enough more money. • So even if we can’t say exactly WHY they are false, they are. • Some philosophers reject premise #2 saying there IS a precise point, even if we don’t know where that point is. [what would Siddhartha say??]

  5. Slippery Slopes • Like heaps, these arguments rely on the existence of borderline cases to show that there is no real difference between two concepts or situations. • Just as with heaps, when many small differences make a big difference, these arguments are fallacious, because a smooth spectrum of examples is not sufficient to deny differences at each endpoint. • Three types: • Conceptual: Uses borderline cases to show that there is no difference between two concepts such as sane & insane. • Fairness: How can it be “fair” to treat people differently on either side of a line? • Causal: If we permit one thing we’ll end up with a situation we don’t want..

  6. Slippery Slopes: Fairness • The implication is that there is no way to draw lines “fairly.” • Asking where we draw the line doesn’t preclude having a clear idea of a concept. • The fact is that we draw those lines all the time – we have to. What happens when we don’t? • Examples: • Grades, Taxes , the Law [eg. van or home?] • Welfare and other benefit programs [anything with a “means” test] • Admission to the bar or to the medical profession. • Other examples?

  7. Slippery Slopes: Causal An example of a causal slippery slope argument: • If we allow terminally ill people to choose to die [called voluntary euthanasia] • Then it’s just a small step to involuntary euthanasia of the terminally ill • And then it’s just a small step to killing people who are handicapped or retarded or don’t meet other social standards. • Thus we should not allow voluntary euthanasia at all. “Domino Effect” – used to support Vietnam War.

  8. Ambiguity and Equivocation • Ambiguity occurs when you don’t know which meaning to attach to a word. • Differs from Vagueness, where the word or phrase has is no clear meaning • Fallacy of Equivocation: playing with the meanings for a single word or phrase. • Check the validity of an argument containing an equivocation by rephrasing so that the word has the same meaning in both premises & conclusion. • Have fun with this one!Nothing is better than a ham sandwich. Something is better than nothing Something is better than a ham sandwich

  9. FALLACIES OF RELEVANCE • These work because we normally assume a person’s comments are relevant. [see Ch. 1] • It is conversationally implied there is some connection between what you say and what you are arguing for • You check for these by crossing out all irrelevant claims in the argument. • Two types • Ad Hominem arguments • Appeals to Authority

  10. Ad Hominem I • These arguments are directed against the person presenting an argument rather than against the claims of the argument itself. • These argument often cite personal characteristics that have nothing to do with the issue. • The intention is to distract the listener. • Sometimes the background of the speaker is relevant – examples from court cases.

  11. Ad Hominem II • Three types of “ad hominem” arguments • Deniers: Denying the truth of what is said by showing the person is unreliable. • Silencers: Questioning a person’s right to make a claim without attacking the truth. Examples? • Dismissers: Dismissing a speaker as untrustworthy and unreliable. • Each type can be justified in certain circumstances and unjustified in others. Examples? • The fallacy usually falls into the category of unjustified deniers.

  12. Ad Hominem III • Evaluating these arguments: • Is it about the person’s right to speak? Someone’s reliability? Or about the truth, soundness or strength of what is claimed? • Do the premises provide adequate support for the conclusion? • The issue of inconsistency: tu quoque or “look who’s talking?” • The “genetic fallacy” – when you are looking at the origins of the speakers argument rather than the claims. • Marxism – refutes all other arguments because they are based on capitalism.

  13. Ad Hominem IV A famous one is from Plato’s Republic- Book 1..When we had got to this point in the argument, and every one saw that the definition of justice had been completely upset, Thrasymachus, instead of replying to me, said: -- Tell me, Socrates, have you got a nurse? -- Why do you ask such a question, I said, when you ought rather to be answering? --Because she leaves you to snivel, and never wipes your nose: she has not even taught you to know the shepherd from the sheep. . Which kind is it?

  14. Appeals to Authority • Often there is nothing wrong in appealing to authority -- related to “assuring.” • Abuses: Fallacy of Relevance • Entertainment figures supporting politicians. • You need an expert in the field to judge the relevance of the claims. • Questions to ask? • Does the “expert” claim knowledge about things they could not possibly posses? • Is it a field where claims CAN be settled by experts? • Has the authority been cited correctly? • Can the authority be trusted to tell the truth? • Why is an appeal to authority being made at all?

  15. Fallacies of Vacuity: Circular Reasoning • These are arguments that don’t go anywhere. • Instead of giving reasons for a claim, you just reassert the claim. • Arguments like this can be valid, but they won’t be sound. • People hide circular reasoning by restating the conclusion in different words. • See the “arms race” example in Fogelin. • Or making sure there are a lot of sub-arguments and tangent between the claim and the conclusion.

  16. Fallacies of Vacuity: Begging the Question • It is always wrong to murder human beingsCapital punishment involves murdering human beings. . Capital punishment is wrong. . • The first premise is true by definition as murder IS defined as “wrongful killing” • The problem is in the second premise: calling capital punishment “murder” is begging the question as that’s what you are trying to prove. • Similar definition slippages happen in the abortion debate on fetuses as “unborn children” or “part of the woman’s body”

  17. Fallacies of Vacuity: Self-Sealers • These are arguments that no evidence can refute. • Unfortunately they are vacuous, that is empty. • Example: If a clairvoyant’s prediction fails she says this proves that someone set up bad vibes to interfere with her prediction. • People who use these arguments often shift their ground. • How to challenge? • Ask what evidence could possibly prove it wrong? • Another approach is to say that if your argument cannot predict that certain events will or will not occur, then it has shown nothing. • Like other fallacies of vacuity the ground often shifts.

  18. Fallacies of Vacuity: Self-Sealers • Ideologies tend to be self-sealers: • If you don’t believe in Marxism it just shows that your social consciousness has not been raised. • And that you need re-education. • Psychoanalytic theory can have the same problem when they say that disagreement with certain claims just shows that you are repressed. • Denial is seen as repression of those desires. • Self-sealing arguments can also be true by definition. • For example, you can define “selfish” so that it includes everyone. • But then the word ceases to have meaning.