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Discusses fallacies of relevance and fallacies of insufficient evidence.

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  1. Zaid Ali Alsagoff [email_address] Module 4: Fallacies
  2. Man or Woman? Source: http://www.coolopticalillusions.com/manwoman.htm
  3. How many legs does this elephant have? Source: http://www.coolopticalillusions.com/elephantlegs.htm
  4. Which officer is the tallest? Source: http://www.coolopticalillusions.com/optical_illusions_images_2/giant_man.htm
  5. Is this wave moving? Source: http://www.grand-illusions.com/opticalillusions/oblong_wave/
  6. AirAsia + Girls = Fun Analyze + Evaluate = Your Opinion? Target Audience?
  7. Module 4: Fallacies <ul><li>Fallacies </li></ul><ul><li>of Relevance </li></ul>2. Fallacies of Insufficient Evidence Fallacies What mistake!!!
  8. 4.0 What is a Fallacy? <ul><li>A (logical) fallacy is an argument that contains a mistake in reasoning . </li></ul><ul><li>Fallacies can be divided into two general types: </li></ul><ul><ul><li>Fallacies of Relevance Arguments in which the premises are logically irrelevant to the conclusion. </li></ul></ul><ul><ul><li>Fallacies of Insufficient Evidence Arguments in which the premises, though logically relevant to the conclusion, fail to provide sufficient evidence for the conclusion. </li></ul></ul>
  9. Fallacies of Relevance “ There is nothing so stupid as an educated man, if you get him off the thing he was educated in” - Will Rogers
  10. 4.1 Fallacies of Relevance <ul><li>A statement is RELEVANT to another statement if it provides at least some reason for thinking that the second statement is true or false. </li></ul><ul><li>There are three ways in which a statement can be relevant or irrelevant to another: </li></ul><ul><ul><li>A statement is positively relevant to another statement if it provides at least some reason for thinking that the second statement is true . </li></ul></ul><ul><ul><li>A statement is negatively relevant to another statement if it provides at least some reason for thinking that the second statement is false . </li></ul></ul><ul><ul><li>A statement is logically irrelevant to another statement if it provides no reason for thinking that the second statement is either true or false. </li></ul></ul>
  11. 4.1 Fallacies of Relevance Two Wrongs Make a Right Equivocation Scare Tactics Red Herring Begging the Question Straw Man Look Who’s Talking Bandwagon Argument Attacking the Motive Appeal to Pity Personal Attack
  12. 4.1.1 Personal Attack <ul><li>Example: </li></ul><ul><li>Professor Doogie has argued for more emphasis on music in our F2F classes to facilitate creativity. But Doogie is a selfish bigheaded fool. I absolutely refuse to listen to him. </li></ul>Personal Attack When an arguer rejects a person’s argument or claim by attacking the person’s character rather than examining the worth of the argument or claim itself. <ul><ul><ul><ul><ul><li>1. X is a bad person. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. Therefore X's argument must be bad. </li></ul></ul></ul></ul></ul>Pattern
  13. 4.1.2 Attacking the Motive <ul><li>Example: </li></ul><ul><li>Donald Trump has argued that we need to build a new campus. But Trump is the owner of Trump’s Construction Company. He’ll make a fortune if his company is picked to build the new campus. Obviously, Trump’s argument is a lot of self-serving nonsense. </li></ul>Attacking the Motive When an arguer criticizes a person’s motivation for offering a particular argument or claim, rather than examining the worth of the argument or claim itself. <ul><ul><ul><ul><li>X has biased or has questionable motives. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Therefore, X’s arguments or claim should be rejected . </li></ul></ul></ul></ul>Pattern
  14. 4.1.3 Look Who’s Talking <ul><li>Example: </li></ul><ul><li>Doctor: You should quite smoking. </li></ul><ul><li>Patient: Look who’s talking! I’ll quit when you do, Dr. Smokestack! </li></ul>Look Who’s Talking (tu quoque) When an arguer rejects another person’s argument or claim because that person is a hypocrite. <ul><ul><ul><ul><li>X fails to follow his or her own advice. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Therefore, X’ s claim or argument should be rejected. </li></ul></ul></ul></ul>Pattern
  15. 4.1.4 Two Wrongs Make a Right <ul><li>Examples: </li></ul><ul><li>“ I don’t feel guilty about cheating on Zaid’s online quiz. Half the class cheats on his quiz.” </li></ul><ul><li>“ Why pick on me, officer? Everyone else is using drugs.” </li></ul>Two Wrongs Make a Right When an arguer attempts to justify a wrongful act by claiming that some other act is just as bad or worse. <ul><ul><ul><ul><ul><li>1. Others are committing worse or equally bad acts. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. Therefore my wrongful act is justified. </li></ul></ul></ul></ul></ul>Pattern
  16. 4.1.5 Scare Tactics <ul><li>Example: </li></ul><ul><li>Diplomat to diplomat: I’m sure you’ll agree that we are the rightful rulers of the Iraq. It would be regrettable if we had to send armed forces to demonstrate the validity of our claim. </li></ul>Scare Tactics When an arguer threatens harm to a reader or listener and this threat is irrelevant to the truth of the arguer’s conclusion. <ul><ul><ul><ul><ul><li>Fear is a powerful motivator – so powerful that it often </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>causes us to think and behave irrationally. </li></ul></ul></ul></ul></ul>Remember
  17. 4.1.6 Appeal to Pity <ul><li>Example: </li></ul><ul><li>Student to Lecturer: I know I missed half your classes and failed all my quizzes and assignments. First my cat died. Then my girlfriend told me she has found someone else. With all I went through this semester, I don’t think I really deserve an F. Any chance you might cut me some slack and change my grade to a C or a D? </li></ul>Appeal to Pity When an arguer attempts to evoke feelings of pity or compassion, where such feelings, however understandable, are not relevant to the truth of the arguer’s conclusion. <ul><ul><ul><ul><ul><li>P is presented, with the intent to create pity. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. Therefore claim C is true. </li></ul></ul></ul></ul></ul>Pattern
  18. 4.1.7 Bandwagon Argument <ul><li>Example: </li></ul><ul><li>All the really cool UNITAR students smoke cigarettes. Therefore, you should, too. </li></ul>Bandwagon Argument (Peer Pressure) When an arguer appeals to a person’s desire to be popular, accepted, or valued, rather than to logically relevant reasons or evidence. <ul><ul><ul><ul><ul><li>1. Most (or a select group of) people believe or do X. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. Therefore, you should believe or do X. </li></ul></ul></ul></ul></ul>Pattern
  19. 4.1.8 Straw Man <ul><li>Example: </li></ul><ul><li>Singh and Karen are arguing about cleaning out their closets: </li></ul><ul><li>Suzie: &quot;We should clean out the closets. They are getting a bit messy.“ </li></ul><ul><li>Singh: &quot;Why, we just went through those closets last year. Do we have to clean them out everyday?&quot; </li></ul><ul><li>Suzie: &quot;I never said anything about cleaning them out every day. You just want too keep all your junk forever, which is just ridiculous.&quot; </li></ul>Straw Man When an arguer misrepresents another person’s position to make it easier to attack. <ul><ul><ul><li>1. Person A has position X. </li></ul></ul></ul><ul><ul><ul><li>2. Person B presents position Y (which is a distorted version of X). </li></ul></ul></ul><ul><ul><ul><li>3. Person B attacks position Y. </li></ul></ul></ul><ul><ul><ul><li>4. Therefore X is false/incorrect/flawed. </li></ul></ul></ul>Pattern
  20. 4.1.9 Red Herring <ul><li>Example: </li></ul><ul><li>&quot;I think there is great merit in making the requirements stricter for the graduate students. I recommend that you support it, too. After all, we are in a budget crisis and we do not want our salaries affected.&quot; </li></ul>Red Herring When an arguer tries to sidetrack his audience by raising an irrelevant issue, and then claims that the original issue has been effectively settled by the irrelevant diversion. <ul><ul><li> 1. Topic A is under discussion. </li></ul></ul><ul><ul><li> 2. Topic B is introduced under the guise of being relevant to topic A (when topic B is actually not relevant to topic A). 3. Topic A is abandoned. </li></ul></ul>Pattern
  21. 4.1.10 Equivocation <ul><li>Example: </li></ul><ul><li>In the summer of 1940, Londoners were bombed almost very night. To be bombed is to be intoxicated. Therefore, in the summer of 1940, Londoners were intoxicated almost every night. </li></ul>Equivocation When an arguer uses a key word in an argument in two (or more) different senses. <ul><ul><ul><ul><ul><li>Fallacies of Equivocation can be difficult to spot because </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>they often appear valid, but they aren’t. </li></ul></ul></ul></ul></ul>Remember
  22. 4.1.11 Begging the Question <ul><li>Example: </li></ul><ul><li>I am entitled to say whatever I choose because I have a right to say whatever I please. </li></ul>Begging the Question When an arguer states or assumes as a premise (reason) the very thing he is seeking to probe as a conclusion. <ul><ul><ul><ul><ul><li>Arguing in a circle – A because B, B because A. </li></ul></ul></ul></ul></ul>Reason
  23. <ul><li> I'm trying hard to understand this guy who identifies himself as a security supervisor and criticizes the police officers in this area. I can only come up with two solutions. One, he is either a member of the criminal element, or two, he is a frustrated security guard who can never make it as a police officer and figures he can take cheap shots at cops through the newspaper (adapted from a newspaper call-in column). </li></ul>4.1 Mini Quiz – Question 1 <ul><li>Which fallacy? </li></ul><ul><li>Loaded Question </li></ul><ul><li>Personal Attack </li></ul><ul><li>Bandwagon Argument </li></ul><ul><li>Scare Tactics </li></ul>
  24. <ul><li> The Red Cross is worried about the treatment of the suspected terrorists held by the U.S. at Guantanamo Bay, Cuba. What do they want the U.S. to do with them, put them on the beaches of Florida for a vacation or take them skiing in the Rockies? Come on, let's worry about the Americans. (adapted from a newspaper call-in column) </li></ul>4.1 Mini Quiz – Question 2 <ul><li>Which fallacy? </li></ul><ul><li>Bandwagon Argument </li></ul><ul><li>Personal Attack </li></ul><ul><li>Straw Man </li></ul><ul><li>Scare Tactics </li></ul>
  25. Fallacies of Insufficient Evidence “ The foolish and the dead alone never change their opinion.” - James Russell Lowell
  26. 4.2 Fallacies of Insufficient Evidence <ul><li>Arguments in which the premises, though logically relevant to the conclusion, fail to provide sufficient evidence to support the conclusion. </li></ul>
  27. 4.2 Fallacies of Insufficient Evidence Hasty Generalizations Inconsistency Loaded Question Weak Analogy False Alternatives Slippery Slope Appeal to Ignorance Questionable Cause Inappropriate Appeal to Authority
  28. 4.2.1 Inappropriate Appeal to Authority <ul><li>Example: </li></ul><ul><li>My dentist told me that aliens built the lost city of Atlantis. So, it’s reasonable to believe that aliens did build the lost city of Atlantis. </li></ul>Inappropriate Appeal to Authority Citing a witness or authority that is untrustworthy. <ul><ul><ul><ul><ul><li>Authority Assessment </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Is the source an authority on the subject at issue? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Is the source biased ? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Is the accuracy of the source observations questionable? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Is the source known to be generally unreliable ? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Has the source been cited correctly ? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Does the source’s claim conflict with expert opinion? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Can the source’s claim be settled by an appeal to expert opinion? </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Is the claim highly improbable on its face? </li></ul></ul></ul></ul></ul>Tips
  29. 4.2.2 Appeal to Ignorance <ul><li>Example: </li></ul><ul><li>Yoda must exist. No one has proved that he doesn’t exist. </li></ul>Appeal to Ignorance Claiming that something is true because no one has proven it false or vice versa. Agree I do! <ul><ul><ul><ul><ul><li>“ Not proven, therefore false” </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>If such reasoning were allowed, we could prove almost </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>any conclusion. </li></ul></ul></ul></ul></ul>Remember
  30. 4.2.3 False Alternatives <ul><li>Example: </li></ul><ul><li>The choice in this MPM election is clear: Either we elect Zubaidah as our next president, or we watch our MPM unity slide into anarchy and frustration. Clearly, we don’t want that to happen. Therefore, we should elect Zubaidah as our next president. </li></ul>False Alternatives Posing a false either/or choice. <ul><ul><ul><ul><ul><li>Fallacy of false alternatives can involve more than </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>two (2) alternatives . It can also be expressed as a </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>conditional (i f-then ) statement. </li></ul></ul></ul></ul></ul>Remember
  31. 4.2.4 Loaded Question <ul><li>Example: </li></ul><ul><li>Lee: Are you still friends with that loser Richard? </li></ul><ul><li>Ali: Yes. </li></ul><ul><li>Lee: Well, at least you admit he’s a total loser. </li></ul>Loaded Question Posing a question that contains an unfair or unwarranted presupposition. <ul><ul><ul><ul><ul><li>To respond to a loaded question effectively , one must </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>distinguish the different questions being asked and respond </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>to each individually. </li></ul></ul></ul></ul></ul>Tip
  32. 4.2.5 Questionable Cause <ul><li>Example: </li></ul><ul><li>Sarah gets a chain letter that threatens her with dire consequences if she breaks the chain. She laughs at it and throws it in the garbage. On her way to work she slips and breaks his arm. When she gets back from the hospital she sends out 200 copies of the chain letter, hoping to avoid further accidents. </li></ul>Questionable Cause Claiming, without sufficient evidence, that one thing is the cause of something else. <ul><ul><ul><ul><ul><li>1. A and B are associated on a regular basis. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. Therefore A is the cause of B. </li></ul></ul></ul></ul></ul>Pattern
  33. 4.2.6 Hasty Generalization <ul><li>Example: </li></ul><ul><li>Norwegians are lazy. I have two friends who are from there, and both of them never prepare for class, or do their homework. </li></ul>Hasty Generalization Drawing a general conclusion from a sample that is biased or too small. <ul><ul><ul><ul><li>1. A biased sample is one that is not representative of the target population. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>2. The target population is the group of people or things that the </li></ul></ul></ul></ul><ul><ul><ul><ul><li>generalization is about. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>3. Hasty generalizations can often lead to false stereotypes . </li></ul></ul></ul></ul>Pattern
  34. 4.2.7 Slippery Slope <ul><li>Examples: </li></ul><ul><li>“ The Malaysian militarily shouldn't get involved in other countries. Once the government sends in a few troops, it will then send in thousands to die.&quot; </li></ul>Slippery Slope Claiming, without sufficient evidence, that a seemingly harmless action, if taken, will lead to a disastrous outcome. <ul><ul><ul><ul><ul><li>The arguer claims that if a certain seemingly harmless action, A, is permitted, A will lead to B, B will lead to C, and so on to D. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>The arguer holds that D is a terrible thing and therefore should not be permitted. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>In fact, there is no good reason to believe that A will actually lead to D. </li></ul></ul></ul></ul></ul>Pattern
  35. 4.2.8 Weak Analogy <ul><li>Example: </li></ul><ul><li>Nobody would buy a car without first taking it for a test drive. Why then shouldn’t two mature UNITAR students live together before they decide whether to get married? </li></ul>Weak Analogy Comparing things that aren’t really comparable. <ul><ul><ul><ul><ul><li>1. List all important similarities between the two cases. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>2. List all important dissimilarities between the two cases. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>3. Decide whether the similarities or dissimilarities are </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>more important. </li></ul></ul></ul></ul></ul>Tip
  36. 4.2.9 Inconsistency <ul><li>Example: </li></ul><ul><li>Note found in a Forest Service Suggestion box: Park visitors need to know how important it is to keep this wilderness area completely pristine and undisturbed. So why not put up a few signs to remind people of this fact? </li></ul>Inconsistency Asserting inconsistent or contradictory claims. <ul><ul><ul><ul><ul><li>It is also a mistake to cling stubbornly to an old idea when new </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>information suggests that the idea is false. </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Open-minded to new ideas = Learning </li></ul></ul></ul></ul></ul>Remember
  37. <ul><li>What's to say against [cigars]? They killed George Burns at 100. If he hadn't smoked them, he'd have died at 75. (Bert Sugar, quoted in New York Times, September 20, 2002) </li></ul>4.2 Mini Quiz – Question 1 <ul><li>Which fallacy? </li></ul><ul><li>Questionable Cause </li></ul><ul><li>Hasty Generalization </li></ul><ul><li>Slippery Slope </li></ul><ul><li>Weak Analogy </li></ul>
  38. <ul><li>According to North Korea's official state-run news agency, &quot;a war between North Korea and the United States will end with the delightful victory of North Korea, a newly emerging military power, in 100 hours. . . . The U. S. [will] be enveloped in flames. . . and the arrogant empire of the devil will breathe its last&quot;. Given that this prediction comes from the official North Korean news agency, it is probably true. </li></ul><ul><li>(Passage quoted in Nicholas D. Kristof, &quot;Empire of the Devil,&quot; New York Times , April 4, 2003) </li></ul>4.2 Mini Quiz – Question 2 <ul><li>Which fallacy? </li></ul><ul><li>Inappropriate Appeal to Authority </li></ul><ul><li>Appeal to Ignorance </li></ul><ul><li>False Alternatives </li></ul><ul><li>Loaded Question </li></ul>
  39. <ul><li> Jurors in tobacco lawsuits should award judgments so large that they put tobacco companies out of business. Respecting the right of tobacco companies to stay in business is akin to saying there are &quot;two sides&quot; to slavery... </li></ul><ul><li>(Anti-tobacco lawyer, quoted in George F. Will, &quot;Court Ruling Expresses Anti-Smoking Hypocrisy,&quot; Wilkes-Barre Times Leader , May 25, 2003) </li></ul>4.2 Mini Quiz – Question 3 <ul><li>Which fallacy? </li></ul><ul><li>Loaded Question </li></ul><ul><li>Hasty Generalization </li></ul><ul><li>Slippery Slope </li></ul><ul><li>Weak Analogy </li></ul>
  40. Group Activity <ul><li>Break into groups of 4 - 6, and construct five (5) fallacious arguments. </li></ul><ul><li>Each group can choose any of the 20 fallacies discussed, but must construct at least two fallacious arguments of each category : Fallacies of Relevance & Fallacies of Insufficient Evidence ). </li></ul><ul><li>The constructed fallacious arguments must discuss the topics specified in the template provided (Business, Education, Information Technology, Environment, and Tourism). </li></ul>Group presentation & discussion. 15 min The Group leader must submit their findings in hard-copy or soft-copy format to the lecturer before or during the next class. Document constructed arguments into the template provided. 5 min Construct 5 fallacious arguments. 20 min
  41. Summary – 20 Common Fallacies Fallacies of Insufficient Evidence Arguments in which the premises, though logically relevant to the conclusion, fail to provide sufficient evidence for the conclusion. Fallacies of Relevance Arguments in which the premises are logically irrelevant to the conclusion. <ul><li>Inappropriate Appeal to Authority </li></ul><ul><li>Appeal to Ignorance </li></ul><ul><li>False Alternatives </li></ul><ul><li>Loaded Question </li></ul><ul><li>Questionable Cause </li></ul><ul><li>Hasty Generalization </li></ul><ul><li>Slippery Slope </li></ul><ul><li>Weak Analogy </li></ul><ul><li>Inconsistency </li></ul><ul><li>Personal Attack </li></ul><ul><li>Attacking the Motive </li></ul><ul><li>Look Who’s Talking </li></ul><ul><li>Two Wrongs Make a Right </li></ul><ul><li>Scare Tactics </li></ul><ul><li>Appeal to Pity </li></ul><ul><li>Bandwagon Argument </li></ul><ul><li>Straw Man </li></ul><ul><li>Red Herring </li></ul><ul><li>Equivocation </li></ul><ul><li>Begging the Question </li></ul>Fallacy An argument that contains a mistake in reasoning .
  42. Any Questions?
  43. The End
  44. References <ul><li>Book </li></ul><ul><li>Chapter 5 (Logical Fallacies -1) & 6 (Logical Fallacies -2): G Bassham, W Irwin, H Nardone, J M Wallace, Critical Thinking: A Student's Introduction , McGraw-Hill International Edition, 2007 </li></ul><ul><li>O n l i n e R e s o u r c e s </li></ul><ul><li>Fallacies (The Nizkor Project): http:// www.nizkor.org /features/fallacies/ </li></ul><ul><li>Cool Optical Illusions: http://www.coolopticalillusions.com/ </li></ul>
  45. Contact Details Zaid Ali Alsagoff UNIVERSITI TUN ABDUL RAZAK 16-5, Jalan SS 6/12 47301 Kelana Jaya Selangor Darul Ehsan Malaysia E-mail: [email_address]     Tel: 603-7627 7238 Fax: 603-7627 7246