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Fallacies. Ignorance is not bliss… . What is a fallacy?. an error in the reasoning process jumping to a conclusion an appeal that does not support an argument. The three criteria for reliable reasoning:. sufficiency relevance acceptability. Inductive Reasoning.
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Fallacies Ignorance is not bliss…
What is a fallacy? • an error in the reasoning process • jumping to a conclusion • an appeal that does not support an argument The three criteria for reliable reasoning: • sufficiency • relevance • acceptability
Inductive Reasoning • a general conclusion based on specific evidence • conclusion goes beyond observations that led to it • there is always a gap between evidence and conclusion (called an inductive leap) • we use the three criteria to try and minimize the gap • we use questions to test the quality of an induction • we use logical fallacies to eliminate errors in reasoning
Inductive Reasoning • is the claim a clear one? • is the claim a strong one? • does the hypothesis account for all the facts? • do you know any relevant facts which conflict? • does another hypothesis also explain the same facts? • what further evidence is needed for support? • what is the source of the evidence?
Catalogue of Inductive Fallacies Hasty Generalization:an argument in which the premises fail to provide sufficient support for the claim. It is a vast claim made with insufficient evidence • Teachers have it made. I have a cottage next door to a teacher, and all he does all summer is swim, sail, and relax in the sun • When I was in Detroit last week, this huge black guy mugged me. Blacks should be sent back to Africa. • President Clinton’s scandal just shows that politicians really have no morals. • I read an editorial in the Sault Star about teens that was totally biased. That paper is useless! • Old people should have their driver’s licenses suspended. Some old geezer almost mowed me down in the parking lot.
Catalogue of Inductive Fallacies Non Sequitur:the premise is irrelevant and therefore does not prove the claim. The claim does not follow logically from the reasons • The Minister of Health for Canada was asked to investigate the validity of the nutritional claims made by Kellogg’s for their product Corn Flakes. The response in parliament was: “As for the nutritional value of Corn Flakes, the milk you have with them has great nutritional value.” • A doll sold at Christmas was found to have a sharp spike protruding from its neck when the head was removed (which children did quite easily). When a complaint was received by Consumer Affairs, the response was: “All the legislation in Ontario won’t protect a child from the normal hazards of everyday life.” • Why can’t my curfew be 1:00 a.m.? Brian’s mom lets him stay out ‘til 1:00. • Avatar is the best movie I’ve ever seen. It will definitely win best picture at the Academy Awards.
Catalogue of Inductive Fallacies Problematic Premise:This fallacy occurs when one or more of the reasons is unacceptable because of lack of authority or lack of truth. An undefended reason which requires defense is labelled problematic. • Many young people who today hold responsible jobs were once the recipients of good beatings from their parents. If there are any bleeding hearts out there who think this is harsh, let them read Proverbs in the Bible. “Spare the rod, spoil the child”. • People should be able to go out in public without clothes on. I heard Howard Stern say so on his show. Man, I love that guy. • We have too many laws in Ontario. People are tired of being controlled. If we just let the people follow their instincts, their good human nature will prevail and they will do the right thing. We should get rid of all those restrictive laws! • You had better be good and noble in this life, because if you aren’t, you’ll be reincarnated as a dung beetle in your next life.
Catalogue of Inductive Fallacies Causal Connection:In this fallacy, two events are connected without proof in a cause/effect relationship. One thing is believed to have caused the other to happen without proof. This fallacy is also known as post hoc ergo propter hoc (after this, therefore, because of this) • I don’t wanna say nuthin, but I know he didn’t have a drinkin’ problem ‘fore he met her. • She’s lovely! She’s engaged! She uses Oil of Olay! • Ever since we changed to Celsius, our weather has gotten colder. • any and ALL superstitions are causal connections. • Sex education leads to promiscuity, unwanted pregnancies, and infidelity. • You shouldn’t teach critical thinking in India because it will cause the breakdown of their social system.
Catalogue of Inductive Fallacies Slippery Slope:This fallacy is a causal connection taken too far, often indicating a worst-case scenario in “if this continues, then this will happen” mode. An argument is slippery when it designates a first and last step in a causal chain, when the intervening steps have not occurred. • Smoking marijuana leads to harder drugs like crack and then you’re dead. • If we let women become CEOs, you can kiss corporate America good-bye. • Don’t stop reading your Bible. Before long, you’ll be breaking all of the commandments with a blatant disregard for human life. • If you have no problem with gum chewing in class, then why not let students eat and drink as well? Hell, let’s just destroy the blackboards, bring in a disco ball and they can bump and grind naked in anarchic atavism.
Catalogue of Inductive Fallacies Red Herring:This fallacy is also known as distraction, a form of non sequitur, which puts up a smoke screen to cloud the issue.Sometimes the support shifts to another point entirely to lead the reader astray. • Under-aged drinking laws should definitely be tougher. Drunk driving laws are even worse because other people’s lives are at stake. Death by car? You may as well just give people automatic weapons. It’s ridiculous. • Yes the water in Walkerton tastes a bit funny, but did you know that those darn teachers, who are public employees, paid by your tax dollars, are making gross amounts of money working from only 9:00 to 3:00? Plus they get all the major holidays off? What gives?? (Mike Harris) • English? Pfftt… who needs that? I’m never going to England. Uptight, mannerly idiots who are engrossed in their glorious soccer team instead of the fact that they have bad teeth. Big book of British smiles anyone? • There’s no way O.J. did it. He is in the Football Hall of Fame. He’s also an actor. Did you see him in Airplane? Actors are such great people. Keanu Reeves is awesome!
Catalogue of Inductive Fallacies Straw Man:this fallacy is a misrepresentation of someone else's position so that it can be attacked more easily (i.e.) a “straw” version. After the misrepresented position is attacked and defeated, the arguer concludes that the original position has been demolished. • Abortion is murder. (Now spend 10 minutes proving that murder is awful, then come back at the end and say again that abortion is wrong…) • What I object to most about those people who oppose capital punishment is that they believe that the lives of convicted murderers are more important than the lives of the police and prison guards who protect us. But, obviously, since the lives of those who protect us are of the greatest value, no one should oppose capital punishment. • “I'm a very controversial figure to the animal rights movement. They no doubt view me with some measure of hostility because I am constantly challenging their fundamental premise that animals are superior to human beings.” (Rush Limbaugh)
Catalogue of Inductive Fallacies The following 5 fallacies are the result of pre-judgment or prejudice. Judgment is the process of reaching a conclusion after a consideration of the facts. Prejudice is the process of reaching a conclusion before consideration of the facts; hence, it is illogical. Labelling:This fallacy is name-calling. A label is attached to a person, thing, or issue which causes it to be pre-judged negatively. Labels are easy to apply but difficult to remove. • People who disagree with our policies are ignorant, anti-Canadian dorks. • Shows like Ellen should be taken off the air – she’s just a faggot. • CSI Miami is the stupidest show I’ve ever watched. David Caruso is a tool. • Some of Ontario’s laws are Draconian – our leaders are just a bunch Fascists. • I don’t agree with your views on abortion. You’re an idiot and your friends are tramps.
Catalogue of Inductive Fallacies Stereotyping:This fallacy occurs when a person has an unvarying conception of a person, group, idea, etc. which allows for no individuality or critical judgment. It is the placing of people into pre-conceived slots in your mind. • Don’t expect much from that guy. He goes to the Hank. • Americans annoy me. They are loud, arrogant, obnoxious people. • That basketball team must be awesome. Look at all the black dudes. • We should get rid of welfare. Those people are just milking the system. • Females shouldn’t take up space in university math classes. They belong in easier subjects like art, music, or history .
Catalogue of Inductive Fallacies Ad Hominem:This fallacy is an attack on the individual instead of the issue involved. The person’s character, nationality, religion, associates, etc. may be attacked. • That guy shouldn’t run for office. His wife is an alcoholic. • What does he know about social responsibility? He just got out of prison. • It’s easy for you to condemn abortion. You can’t have children. • Chretien wasn’t a good prime minister. He couldn’t even speak properly. • Harper can cut all the federal programs he wants to – he’s a millionaire. It won’t affect him at all.
Catalogue of Inductive Fallacies Ad Populum:This fallacy is an appeal to the emotions or prejudices of a large group (a team, a school, a country, a nationality). It is also termed mass appeal. • Decent, upright citizens will not listen to a word he says. • Our television is made in Canada, by Canadians, for Canadians. • The polls suggest the Liberals will win by a landslide. Join the winning team! • Anyone who is the least bit patriotic will vote against Quebec’s separation. • Only an idiot would argue with Flood. • Any teacher who won’t join the protest is a traitor to our cause.
Catalogue of Inductive Fallacies Transfer:This fallacy is a transfer of an idea, feeling, fame, infamy, etc. from one thing to another, without any logical connection. It is a borrowing of prestige or ill-fame and applying it to an unconnected issue. • Wayne Gretzky eats Wheaties – you should too. • We ought to get out of the U.N. Churchill warned us about foreign alliances. • The NDP believes in high income taxes, just like the Marxists… • Bell Telephone ads, like the one where an old man receives a call from his grandson who is on the beach at Dieppe where his grandfather fought in the war. He thanks his grandfather for fighting for freedom and are tears aplenty. • Beautiful people used to sell all kinds of products. • Cut my hair? That sounds like something Hitler would say…
Catalogue of Inductive Fallacies False Analogy:Analogies are used to clarify or explain ideas. When a comparison of two objects (or events) which have at least one area of similarity is used as proof in an argument, the analogy becomes false. There are more dissimilarities than similarities. • Employees are like nails. Just as nails must be hit on the head in order to make them work, so must employees. • Government is like a business. Just as business must be a moneymaking enterprise, so must government. • Minds, like rivers, can be broad. The broader the river, the shallower it is. People with broad minds are shallow. • Smoking is all right, so long as you moderate it. Too much of anything is harmful. Heck, too much applesauce can kill you… • Don’t worry about your boyfriend. So he dumped you. Men are like subways… a new one will come along in 7 minutes.
Catalogue of Inductive Fallacies Ad Misericordiam:This fallacy is also known as a sob story. It is an irrelevant appeal to pity or sympathy. There are legitimate appeals – “Save the Children” campaigns with pictures of real starving children are relevant. • Don’t send me to prison. I have a wife and six kids to support. • Sirrrr… please postpone our fallacy test. We’ve been loaded down with work, October is depressing, our parents don’t understand us, blah blah blah.. • My client shouldn’t be convicted of murdering his parents. He had an unhappy childhood. • You have to give me an “A”. I need it to get into Med school. My entire life will be ruined if I don’t get an “A”. • We can’t possibly pay all those negligent death claims. The airline will fold.
Catalogue of Inductive Fallacies Black & White Thinking:This fallacy oversimplifies an issue by polarizing it into extremes, into an either/or situation. It fails to recognize “gray” or “middle” areas in an issue. • Listen. Either we ban pornography or we let everybody see it. • You’re either deaf or stupid. Which is it? • Are you sane or insane? • The human race is evil by nature or inherently good. Pick one. • Women! They’re either yelling at you because of some misdirected moon-blood aggression or they’re snuggling up all nice and cozy ‘cause they want something… • Of course abortion is a complex issue, but in the end, it stays or it goes. So are you pro-life or pro-choice?
Catalogue of Inductive Fallacies Fallacy of the Beard:This fallacy oversimplifies an issue by failing to recognize differences within the issue. An issue is simplified by seeing one side only, often resulting in sweeping, unsupported, opinionated statements. • All murderers should be executed. • Abortion is wrong and no woman should be allowed to have one. • All art is subversive and all artists should be arrested. • Television is a blight upon our society and should be strictly censored. • Men are slime! • Blacks have natural rhythm.
Catalogue of Inductive Fallacies Ad Baculum:This fallacy is also called appeal to forceor scare tactics. There is a threat of unpleasant conditions if the individual does not agree with the situation. • You had better agree with the Director if you expect to keep your job. • You better stop performing abortions or one day you might just find out how much you value your family. • Accept the truth of the Catholic Church or face the rack. (Inquisition) • The jury better find O.J. innocent or there will be rioting in the streets. • Our paper certainly deserves the support of every German. We shall continue to forward copies to you and hope you will not want to expose yourself to unfortunate circumstances. (Nazi notice to readers who let their subscriptions to the Party newspaper lapse.) • Voting “yes” for the new Iranian constitution will appease the will and wrath of God Almighty. (Ayatollah Khomeini)
Catalogue of Inductive Fallacies Complex Question:This fallacy occurs when two otherwise unrelated points are combined as a single proposition wherein the individual is expected to accept or reject both points when in reality one may be acceptable and the other not. It is often termed a loaded question. • Do you support freedom and the right to bear arms? • Have you stopped beating your wife? • How can you be so stupid? • When are you gonna grow up? • Have you stopped cheating on your math tests? • When are you going to become responsible?
Catalogue of Inductive Fallacies Neglected Aspect:This fallacy involves the selective omission of information necessary for making a valid judgment. It is usually information damaging to the argument which is omitted. • Nuclear power is a great benefit to mankind. It supplies great sources of energy and is used in medical treatment. • Our foreign policy is a great success. Our relations with Britain, the U.S., and France have never been better. • Mom, can I go to the party at Sue’s? Her parents are going to be there. (for the first hour only…) • The U.S. performed very well at the Nagano Olympic winter games. We won women’s hockey gold. • Canada’s record on human rights is the envy of the world. We are a true democracy.
Catalogue of Inductive Fallacies Begging the Question:This fallacy assumes the validity of the claim instead of offering valid reasons to support it. It also takes the form of circularity in which the reason is merely the claim restated.. • Is it right that we prosecute someone who practices euthanasia? Yes. The law is the law. • Foreigners are unreliable because they’re not Canadians. • Should the U.S. bomb Iraq or wait for diplomacy to work? Diplomacy doesn’t work – Nuke ‘em! • Dubya is incapable of making good decisions because he is incompetent. • God must exist. How do you know? Because the Bible says He does. Why should I believe the Bible? Because, it’s the word of God.
Catalogue of Inductive Fallacies Ad Ignorantiam:this fallacy is an appeal to ignorance where someone attempts to argue something false because it cannot be proved true (or vice versa). It misplaces the burden of proof. • I have an invisible fire-breathing dragon in my garage… Until you prove this is false, my claim is true. • No one has ever proved 100% that UFOs exist, therefore they don’t exist. • Obviously UFOs exist – no one has been able to prove that they don’t. * note that appeals to ignorance can work in either direction • No further questions on fallacies? Good. You must be ready for a test. • Of course he’s a communist. There’s nothing in his file to say that he isn’t. • I definitely have ghosts at my camp – I got a weird reading on an EMF meter. No way dude. It’s probably just from nearby electric cables. But there's no electricity in the area. OMG bra, it’s a ghost!!