8Such fallacies are committed with the intent to deceive Such fallacies are committed with the intent to deceive. Keep in mind that the person best able to deceive you - to make his or her argument appear good - is the person who knows these fallacies. Also keep in mind that though the argument may appear to be good, it is not in fact a good argument but a fallacious one.
9There are four basic categories of informal fallacies: Fallacies of RelevanceFallacies of PresumptionFallacies of AmbiguityFallacies in Ordinary Language
10These are the fallacies we will be covering: Fallacies of Relevance:Appeal to forcePhysicalPsychologicalAppeal to pityAppeal to the PeopleBandwagonVanitySnobbery
11Fallacies of Relevance, cont. Ad hominemAbusiveGuilt by AssociationTu QuoqueAppeal to TraditionMisplaced Authority
12Fallacies of Relevance, cont. Hasty GeneralizationBiased SampleUnknowable statisticFalse causeNon sequitorBlack or White
13Fallacies of Presumption Begging the QuestionCircular ReasoningSuppressed Evidence
17So on your next test, you will have to know, what? A Lot of Fallacies!!!!!!
18Fallacies of Relevance Fallacies of this type have one or both of the following characteristics:the premises are logically irrelevant to the conclusionthe connection between the premises and the conclusion is often emotional rather than reasonable
19Appeal to ForceUsing the threat of physical or psychological force to make your opponent concede to your position.
23ExamplesAgree with me or I will punch you in the nose. Now don’t you see why you should agree with me?Mrs.Lodato, I think that I should receive an ‘A’ in this class. I know you will agree. By the way, I know where you live.
24Appeal to Psychological Force Use the threat of psychological damage to your opponent to get them to concede to your position.
25ExamplesIf you do not support your local charity you will burn in hell. Therefore, you should support it.Mrs. Lodato, I think I should receive an ‘A’ in this course. I know you will agree. By the way, my father is on the Board of Directors of this college, and he does everything I tell him to do.
26Appeal to PityHere you appeal to your opponent’s sympathy to make them concede to your position.That is, you attempt to make your opponent believe that you will be miserable unless they concede to your position.
27ExamplesStudent to teacher: You should let me take the exam over, because if I do not pass this course, my mother will never forgive herself, my father will not speak to me, and even the dog will hate me.Lawyer to jury: Please let my client go. Sure he committed the murders, but it wasn’t his fault. He had a bad childhood. His mother left him when he was 18 and someone stole his puppy when he was 19.
28Appeal to the PeopleThis fallacy uses our desires of wanting to be loved, admired, esteemed, valued, recognized, and accepted by others to make us concede to a point or accept a conclusion.
29There are various types of appeals to the people.
30BandwagonHere you argue that since everyone is doing something, your opponent should do it too, otherwise he or she will be left out and not fit in with the crowd.
31Examples Everyone enjoys smoking Whiz, so you should too Don’t be left out in the cold. Come on in and have a Schlitz!!!!
32Appeal to VanityHere someone tells you that if you use a certain product or accept a certain point, you will be admired and sought after like a celebrity who is said to use the product.
34ExamplesLiz Taylor uses Passion perfume, and young, naked men are after her. If you use Passion, young and naked men will be after you.Michael Jordan wears Nikke basketball shoes. If you wear them, you will play like Michael!!!!
35Appeal to SnobberyThis fallacy tells you that if you use a certain product or concede to a certain point, that you are better than everyone else, a member of the select few, and a rare individual.
36Examples Advertisement: “Pass the jelly” Grey Poupon Pierre Cardin luggage - the luggage that quality people buy
37Ad HominemHere you attack the opponent rather than the opponent’s argument.
39AbusiveHere you specifically attack the person under question by calling him or her a name
40ExamplesYou should not vote for Al Gore because he is a ‘liberal’ and will be after your wallet.You can’t trust Joe because he has shifty eyesWhy should we believe you? You have a beard, you smoke cigarettes, and you do not have a job.
42Guilt by AssociationHere you unfairly judge a person or his position because of the company they keep, or because he was associated with a negative past event.
43Examples He must be guilty, because three of his friends are in jail. You should not re-elect Kennedy. Wasn’t his nephew convicted of murder?Don’t date Harriet. I dated her cousin and all she was after was my money.
44Tu Quoque ‘You Too’ ‘Two Wrongs Make A Right” This fallacy is committed when a speaker, trying to show that he is not at fault, argues that his opponent has said or done things just as bad as he, the speaker, has been accused of.
45ExamplesSon to father: Sure I smoke dope dad, but you drink and that is just as bad.Daughter of mother: I should be allowed to date at age 12. You got married when you were 16.Politician: Sure I have made mistakes, but candidate X has admitted to committing adultery.
46Misplaced AuthorityThis fallacy is committed when testimony from an authority is used as evidence in an argument, but the authority quoted is not an authority in the field under discussion.
47Examples Wear Leggs pantyhose. Joe Namath says they are comfortable Psychologist to jury: The defendant does not suffer from schizophrenia. I ought to know, I have a Masters degree in Grief Therapy.Our foreign policy needs revision. Just look at the experts who support my view: Miss Piggy, fifteen logic professors, and five taxi cab drivers.
48Appeal to TraditionThis fallacy is committed when it is argued that because somethingwas done a certain way in the past, it should continue to be done that way.
49ExamplesWomen should not work outside the home. My mother did not work, my grandma did not work, and neither will you.What do you mean I need to change my History text? I have been using this text for the past 50 years and I will continue to use it. Who cares if it is out of print?
50Hasty GeneralizationThis fallacy is committed when the reasoner ‘rushes to judgment’ or a conclusion based on too little evidence.
51ExamplesThe first two apples I took out of that barrel had holes in them, so probably all of the apples in that barrel have holes in them.He must be poor. He has a beard and is wearing dirty clothes. We should give him some money.
52Biased SampleThis fallacy is committed when the sample used as evidence in an argument is not representative of opinions being generalized about.
53Examples100% of the people surveyed believe that drunker driving laws are too strict. (note: the survey was taken outside of liquor stores and bars)100% of the people surveyed believe that abortion is wrong. (note: the survey was given to people on their way out of church on Sunday morning)
54Unknowable StatisticThis fallacy is committed when you cite as evidence statistics that simply cannot be known by anyone.
55ExamplesThe majority of people, although they will never admit it, believe that abortion is wrong.80% of people world-wide believe that there are aliens from other planets among us.
56False Cause Post Hoc, ergo Propter Hoc This fallacy is committed when you assert that because two eventsoccur one after the other, that the first is the cause of the second.
57ExamplesLightning flashed and then the lights went out. The lightning caused the lights to go out.You went in Harriet’s hospital room and then she died. You killed her.
58Non SequitorThis fallacy occurs when the premises of an argument are entirelyirrelevant to the conclusion drawn.
59ExamplesPlato wrote in dialogue form and it is difficult to separate his views from those of his opponents. So he is a lousy philosopher.You did not do your homework today, so you must be a rotten husband to your wife.
60Black or WhiteThis fallacy is committed when you argue that since you opponent doesn’t agree with your position, then he must agree with the extreme of your position. You try to make you opponent or audience think that there are only two choices (yours and the extreme), when in fact there are many.
61ExamplesSo you don’t think that prisoners should be allowed to watch cable. Well, you would have them all in isolation, and eating nothing but bread and water.You don’t believe in buying diamonds for Valentine’s Day? Well, you must think that all women are just here to serve and slave for you.
63Fallacies of Presumption These fallacies occur when the arguments presume - in some way - what they are trying to prove, or they presume evidence of some type.
64There are Many Types of Fallacies of Presumption
65Begging the QuestionThis fallacy occurs when the arguer presents evidence for the conclusion as true, but the evidence presented is either an opinion or the arguer offers no proof that the evidence is in fact true.
66ExamplesTo be a good president, it is necessary to have at least 30 years of political experience. Jesse Jackson has not had that much political experience, so he would not make a good president.To be a good student, you must study at least four hours per night, per subject. Harry works all night and does not have time to study that long. He will fail.
67Circular ReasoningThis fallacy is committed when the argument fails to prove anything because it takes for granted what it is supposed to prove.
68ExamplesBeautiful women are the best type to date because they are beautiful and fun to date.Candidate X must not be trusted because he is deceptive.Abortion is wrong because it is immoral.Smoking marijuana is wrong because taking drugs is wrong.
69Suppressed EvidenceThis fallacy is committed when relevant evidence is purposely omitted in the argument because it is contrary to what the author is trying to prove.
70Examples R.J. Reynolds Tobacco Company memos “Jesse Jackson will not make an effective president because he has never held political office.” Here, the arguer fails to make note of the fact that Jackson does have experience in foreign policy, and he also fails to note that there have been other presidents who never held political office before becoming president.
71Fallacies of Ambiguity These fallacies occur when one word in an argument may betaken to have two or more distinct meanings.
72EquivocationThis fallacy occurs when the same word is used in two different senses in an argument.
73ExamplesEvery mystery is a religious belief and the whereabouts of the killer is a mystery. Therefore, the whereabouts of the killer is a religious belief.Computers get viruses and you have a virus so you must be a computer.
74AmphibolyThis fallacy occurs when the grammar of a statement is ambiguous and allows for more than one interpretation.
75Examples Save trash and waste paper Rummage sale ad: “The ladies will have cast off clothing in the church basement.”
77False AnalogyThis fallacy is committed when you compare two items, and argue that because they have some characteristics in common, they must have another characteristic in common. However, you ignore or fail to point out relevant dissimilarities.
78ExamplesA computer has a memory, can make predictions and can store information. The human mind also does these things. The human mind also dreams, so computers can dream as well.Note: Here the arguer fails to take into consideration relevant differences between the human mind and a computer.
79Slippery SlopeHere it is argued that if one event is allowed to occur, then a whole series of consequences will also occur. Or if you accept one point, then you must accept a series of other points. The consequences may be either good or bad.
80ExamplesMother to daughter (who is on a diet): “If you eat that donut, then you will eat the whole box, and then you will gain back all of your weight, and then you will have to buy all new clothes and and a new car, and you will never get married.Mother to daughter: If you lose weight, you will become a beauty queen, and then a movie star, etc.
81Straw ManHere the arguer misinterprets or misrepresents an argument or position for the purpose of attacking it. He or she then concludes that the real position has been refuted, when in fact the misrepresentation was refuted.
82ExamplesMr. X states: “My opponent in this debate has argued that our prisons release hardened criminals back into society. He recommends more rehabilitation. He mentioned job training, therapy, and other educational programs. Well, I certainly don’t like all the prison riots and so forth,but I don’t think that we should change prisons into schools and hospitals, and certainly not vacation resorts!!!!”
83Red HerringYou commit this fallacy when you introduce a “logically separate and irrelevant issue into the discussion.”
84ExamplesYou say that abortion is wrong and that it is murder. But do you know how many other ‘murders’ are committed by incompetent doctors everyday? A lot, that’s how many.You say that women should have the same rights as men? Now why is such a beautiful woman like yourself worried about such things? You should be worried about getting a rich husband.