Lecture notes - Arguments & fallacies, tetralogue pt1 & pt2 and relativism - acquaintance, description and induction, knowledge of general principles & a priori, universals & knowledge of universals, truth & falsehood and knowledge and probable opinion PDF

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Arguments & Fallacies, Book: Tetralogue - Tetralogue Pt1 & Pt2 and Relativism - Acquaintance, Description and Induction, Book: Meditations. - Knowledge of General Principles & A Prior, Book: Problems of Philosophy. - Universals & Knowledge of Universals, Book: Problems of Philosophy - Truth & False...

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PHIL 102 Week 1 Arguments & Fallacies    

An argument is a set of claims, one of which is meant to be supported by the others. A conclusion is a claim meant to be supported by reasons offered in the argument. A premise is a claim put forth as a reason for a conclusion. As such, an argument is a set of claims that can be divided, or partitioned, into a conclusion and one or more premises.  (Argument = conclusion + premises.)

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Example 1: By the end of September in New England, the leaves are already changing to beautiful browns and reds. The nights are cooler, and the days are noticeably shorter.  Not an argument. Why not?

Example 2: The only possible superpower in the world other than the United States is a unified Europe. But divisions and jealousies that date back centuries ensure that Europe will never present a unified front. Obviously, then, the United States will continue to be the world’s only superpower. This is an argument. What are its premises and conclusion?  Premise 1: The only possible superpower in the world other than the United States is a unified Europe.  Premise 2: Divisions and jealousies that date back centuries ensure that Europe will never present a truly unified front.  Conclusion: The United States will continue to be the world’s only superpower. 

Each time we move from premise(s) to a conclusion, we infer or make an inference.  But how do we recognize premise from conclusion, and so how do we tell whether a set of claims constitutes an argument?  Example: Today is the 3rd. Yesterday was the 2nd.  Here we have a pair of claims. But it is not at all clear whether there is an argument, or, if there is, what argument is being advanced.  Premise: Today is the 3rd. Conclusion: Yesterday was the 2nd.  Premise: Yesterday was the 2nd. Conclusion: Today is the 3rd.  Revision: Today is the 3rd. Therefore, yesterday was the 2nd. OR: Since today is the 3rd, yesterday was the 2nd. We need Inference Indicators to state an argument.  These indicators are not among the set of claims that constitute the argument. Rather, they indicate the inferential ordering of the claims into an argument. Conclusion Indicators (neither exhaustive nor infallible):  Therefore; Hence; Consequently; We may conclude; This entails that; It follows that; Which shows that; Here are some of the reasons why. Premise Indicators (neither exhaustive nor infallible):  Since; Because; For; For the reason that; Seeing as; As is implied by; The reason is that; On account of the fact that. But things aren’t always so cut and dry. There are various complexities that may arise.  For one, premises or conclusions can be implicit, or unstated.  Example: The bigger the burger the better the burger. The burgers are bigger at Burger King.  Example: John cannot have murdered Jones because John does not have a snake tattoo on his left arm.   

Arguments with implicit premises or conclusions are called Enthymemes. We’ve defined arguments as a set of claims. Claims are evaluable as true or false. But sometimes questions, commands, exclamations, and the like, can serve to indicate a claim in an argument.

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Example: Clouds are rolling in, and the wind is picking up. Go check the boat now! Premise 1: The clouds are rolling in. Premise 2: The wind is picking up. Conclusion: You should go check the boat.

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Sometimes arguments can be seen as offering multiple conclusions.  Example: Descartes forgot to pay his gas bill again. It looks like the poor guy is obsessed with finishing the meditations he’s been writing. Anyway, he’ll be cold this winter.  Premise: Descartes forgot to pay his gas bill again.  Conclusion: Descartes is obsessed with finishing the meditations he’s been writing.  Premise: Descartes forgot to pay his gas bill again.  Conclusion: Descartes will be cold this winter.

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Sometimes arguments will contain sub-arguments.  Example: If the crippling debts of Third World nations can be eased, then the national economies of these countries can start to grow at a healthy rate. And if these economies can experience growth, then millions of people can work their way out of poverty and starvation. Fortunately, it is possible to ease the debts of these nations; thus their economies can experience growth. Therefore it is possible for millions of the world’s poorest people to find their way out of the cycle of poverty.  Premise 1: If the debts of Third World nations can be eased, then the national economies of these countries can start to grow at a healthy rate. (If A then B.)  Premise 2: The debts of Third World nations can be eased. (A.)  Intermediate Conclusion: The national economies of these countries can grow at a healthy rate. (So B.)  Premise 1: If the economies of debtor nations can start to grow at a healthy rate, then millions of people can work their way out of poverty. (If B then C.)  Premise 2: The national economy of these nations can grow at a healthy rate. (B.)  Final Conclusion: Millions of people can work their way out of debt. (So C.)  We have defined what an argument is, identified ways of picking them out, and devised a method for putting them in standard form, where we make explicit what are the premises and what are the conclusions (and so the inferential connections that make a set of claims an argument).

But how do we evaluate arguments?  We have said that an argument is a set of claims, one of which is meant to be supported by the others. (Put aside multiple conclusion arguments.)  But there are different sorts of arguments, which can be differentiated by the level of support that the premises are meant to confer on the conclusion.  This gives rise to a distinction between deductive arguments, the premises of which are intended to guarantee the truth of the conclusion, and non-deductive arguments, the premises of which are intended to confer a high degree of probability on the conclusion.  Deductive arguments are characterized as valid or invalid.  A valid (deductive) argument is one in which there is no possible way for the premises to be true and the conclusion false at the same time.  In other words: It must be that if all the premises are true, then the conclusion is true.  Example: All students are studious; all studious people excel; therefore, all students excel.  An argument is invalid if and only if it is not valid.  Example: All students are studious; some studious people are tall; therefore, some students are tall.  But the fact that the premises of a valid deductive argument guarantee its conclusion does not guarantee the truth either of the premises or the conclusion.  Example: All people are numbers; All numbers are funny; therefore, all people are funny.  So a valid argument may have(1) false premises and a true conclusion; (2) false premises and a false conclusion; (3) true premises and a true conclusion. (NOT: true premises and a false conclusion!) 

An argument is sound if and only if it is valid and all of its premises are true.  Example: Today is the 3rd; so yesterday was the 2nd.

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Example: All humans are conscious; Bill Clinton is human; therefore, Bill Clinton is conscious.

How might we test for validity?  By Reductio ad absurdum.  Suppose the premises true and the conclusion false. Do we obtain a contradiction? If so, then the conclusion is true (given the premises).  Non-deductive arguments, recall, do not guarantee the truth of their conclusion. Rather, they confer (when good) a high degree of probability on their conclusion.  Statistical: The inference is from some portion of the population having a certain feature to some individual within the population having that feature.  Example: 90% (most) of UofA students know the capital of Alberta; Jane is a UofA student; therefore, Jane knows the capital of Alberta.  N.B. Adding premises can affect the success of the argument. Contrast with the deductive case.  Inductive Generalizations: the inference is from some sample of a population to all or some percentage of its members.  Example: Every wolverine observed so far has been unfriendly and aggressive. Therefore, all wolverines are unfriendly and aggressive.  Analogical: the inference is from similarity to shared to features.  Example: John’s and Jane’s model M car are comfortable; my new is car is a model M (i.e. similar in make and model); therefore, my new car is comfortable. Exercises 1. Riin had the highest score on the qualifying exam, and so she will get first consideration for the job. The person who gets first consideration almost always does get the job. Thus, it is pretty sure that Riin will get the job.  Does the passage present an argument or not? If it does, is it simple or complex? 2. If a dogs bites the mailman, it must be punished. Our dog Sparky didn’t bite the mailman, so he musn’t be punished.  Is the argument valid? 3. Most intellectuals cannot explain the mathematical supposition called “Goldbach’s Conjecture”. My calculus professor is an intellectual, so he wouldn’t know about the Goldbach thing.  Why is this argument unconvincing? Fallacies of Reasoning  A fallacy is an error in reasoning.  There are two general sorts that we’ll consider: 1. Errors in supporting a claim (i.e. in giving an argument). 2. Errors in criticizing arguments, or in responding to criticism. Five Fallacies of Relevance: 1. Appeal to Ignorance: Because a claim has not been proven false, it is true.  E.g. Astrology has to be right, because over the centuries no one has disproved it. *However, sometimes the appearance of an appeal to ignorance is the result of an unstated premise.  E.g. It has not been shown that there is an elephant in the classroom [i.e. I did not see it], therefore there is no elephant in the classroom. Add the premise: If there were an elephant in the room, then I’d see it. 2. Appeal to Inappropriate Authority: We rely for much of what we believe on the evidence of authority, and citing an authority is a legitimate way of justifying a belief. However, a fallacy is committed when the authority cited is not an authority in the proper area.  E.g. Aldous Huxley was convinced that nearsightedness could be corrected by eye exercises (the Bates Method) and that glasses were unnecessary. He wrote a book on this, and, because of his prominence as a novelist, other people cited him as curing nearsightedness.

3. Appeal to General Belief: The fallacy consists in asserting that a claim is correct just because people generally believe it is. But we have no reason to take what most people believe as a reliable indicator of what is true. 4. Appeal to Popular Attitude and Emotions: Popular attitudes, and emotions associated with them, can be manipulated to incline people to accept claims that have not been demonstrated. Racial fears, patriotic impulses, and the wish to be associated with a special social group are some sources of such sentiments and attitudes.  E.g. I’ll tell you why I believe we were right to go to war with Iraq. It’s because I love my country. If you love it, you’ll agree. 5. The Gambler’s Fallacy:  E.g. According to the law of averages, if I flip a coin, it should come up heads about 50% of the time and come up tails about 50% of the time. The last ten flips have been tails. So, it is well past time for heads to come up. We better bet on heads.  But each flip of the coin is independent of the others. The fallacy is in thinking that heads is “due” to happen. Two Fallacies of Inadequate Evidence: 1. The False Cause: This fallacy involves concluding that because one event occurred before another, the first was the cause of the second. 

E.g. Templeton eats a candy bar then commits murder. It would be fallacious to conclude, on this ground alone, that eating the candy bar caused Templeton to commit the murder.

2. Hasty Generalizations: consists in generalizing on the basis of an inadequate set of cases. 

E.g. Suppose you’re a therapist, and your first two clients lie to you about crucial aspects of their lives. To conclude that all or most clients lie to their therapists would by a hasty generalization.

Four Fallacies of Illegitimate Assumption: 1. False dilemma: arguments that present alternatives as exhaustive and exclusive when they are not.  E.g. You’re either for us or against us. You’re obviously not for us. So, you’re against us.

2. Loaded Question: attempting to get an answer to a question that assumes an unproved assumption.  E.g. Are you still beating your spouse?

3. Begging the Question: When a reason offered for a conclusion is not different from the conclusion.  E.g. James is a murderer because he wrongfully killed someone. 4. Slippery Slope: thinking that when there is no significant difference between adjacent points along a continuum, there is no significant difference between even widely separated points on the continuum. Fallacies of Criticism and Response: 1. Against the Person: rejecting a claim or argument by offering as grounds of some personal characteristic of the person supporting it. 2. You too (special case against the person): rejecting/ deflecting the claim back onto the person. P: Murder is wrong. Q: But you’re a convicted murderer.

3. Pooh-Pooh: to dismiss an argument with ridicule as not worthy of serious consideration. 4. Straw Man: misrepresenting a person’s claim or argument so that it is easy to criticize. 5. Loaded Words: applying judgmental words in argumentation without justification of their application.

 E.g. Medical research on animals simply must be stopped immediately. The torture of innocent creatures is morally indecent....