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Lemon Bay High SchoolAP Language and CompositionENC 1102Mr. Hertz

Please take out a few pieces of paper and a pen or pencil. Write yourname, the date, your class period, and a title at the top of the paper:“Logical Fallacies” Warm Up Prompt: “Whether you know what fallacies are or not, tryto describe at least two situations where an argument is made thatdoes not logically make sense. That is, the argument one is makingmay kind of be valid, but for some reason is not. Do your best toexplain or describe your two arguments.” When we are finished writing, we will share some responses. Pleasetake notes on the class discussion.

Fallacies are common errors inreasoning that will undermine thelogic of your argument. Can be either illegitimatearguments or irrelevant points. Often identified because they lackevidence that supports theirclaim. Avoid fallacies in your ownarguments and watch for them inthe arguments of others.(From Purdue Online Writing Lab)

1. Ad HominemA. A occurs before B. Therefore A is the cause of B.2. Straw ManB. Premise inc. the claim that the conclusion is true.3. Appeal to Common PracticeC. Purported expert makes a claim about a given topic.4. Begging the QuestionD. Attacking someone’s character, not the claim.5. Slippery SlopeE. Irrelevant top is presented to divert attention.6. False DilemmaF. X is commonly accepted, therefore X is correct7. Red HerringG. Conclusion about a large pop. using small sample8. Post Hoc Ergo Propter HocH. Either X is true or Y is True. If Y is false, X is true.9. Hasty GeneralizationI. One event must inevitably follow the other.10. Appeal to AuthorityJ. Substitute one position with closely related position.

Please take notes on the following lecture. You will bepresented with an abundance of information and exampleson fallacies. There will be ten total fallacies in this lesson. For each fallacy: Write the name of the fallacy and underline it. Write the definition of the fallacy Write the “mathematical” example. Choose one more example (there will be several) and write it. Do your best! Ask questions! Seek to understand!

Definition—A claim or argument is rejected on the basis of some irrelevant factabout the author of or the person presenting the claim or argument. Typically, this fallacy involves two steps:1.2.an attack against the character of the person making the claim, her circumstances, orher actions is madeSecond, this attack is taken to be evidence against the claim or argument the person inquestion is making (or presenting). This type of “argument” has the following form:1. Person A makes claim X.2. Person B makes an attack on person A.3. Therefore A’s claim is false. Ad Hominem is a fallacy because the character, circumstances, or actions of aperson do not have a bearing on the truth or falsity of the claim being made.

EXAMPLE: #1:Bill: “I believe that abortion is morally wrong.”Dave: “Of course you would say that, you’re apriest.”Bill: “What about the arguments I gave to supportmy position?”Dave “Those don’t count. Like I said, you’re apriest, so you have to say that abortion is wrong.Further, you are just a lackey to the Pope, so I can’tbelieve what you say.” EXAMPLE #2:How can we accept Jill’s argument in favor ofabortion rights when she herself has had three ofthem?

The Straw Man fallacy is committed:“when a person simply ignores a person'sactual position and substitutes a distorted,exaggerated or misrepresented version of thatposition.” This sort of "reasoning" has the following pattern:1. Person A has position X.2. Person B presents position Y (a distorted version of X).3. Person B attacks position Y.4. Therefore X is false/incorrect/flawed.

EXAMPLE #1:Jones: "The university just cut our yearly budget by 10,000."Smith: "What are we going to do?"Brown: "I think we should eliminate one of the teaching assistantpositions. That would take care of it."Jones: "We could reduce our scheduled raises instead."Brown: "I can't understand why you want to bleed us dry like that,Jones."EXAMPLE #2:Jill: "We should clean out the closets. They are getting a bit messy."Bill: "Why, we just went through those closets last year. Do we have toclean them out everyday?"Jill: "I never said anything about cleaning them out every day. You justwant to keep all your junk forever, which is just ridiculous."

The Appeal to Common Practice is a fallacy with the followingstructure:1. X is a common action.2. Therefore, X is correct/moral/justified/ reasonable, etc. The basic idea behind the fallacy is that the fact that most peopledo X is used as "evidence" to support the action or practice. It is a fallacy because the mere fact that most people dosomething does not make it moral, correct, justified, orreasonable.

EXAMPLE #1:Director Jones is in charge of running a state waste management program. When it isfound that the program is rife with corruption, Jones says "This program has itsproblems, but nothing goes on in this program that doesn't go on in all stateprograms."EXAMPLE #2:"Yeah, I know some people say that cheating on tests is wrong. But we all know thateveryone does it, so it's okay."EXAMPLE #3:"Sure, some people buy into that equality crap. However, we know that everyone payswomen less than men. It's okay, too. Since everyone does it, it can't really be wrong."

A fallacy in which “the premises include the claimthat the conclusion is true or (directly orindirectly) assume that the conclusion is true.” This sort of "reasoning" typically has the followingform: 1. Premises in which the truth of the conclusion is claimed orthe truth of the conclusion is assumed (either directly orindirectly). 2. Claim C (the conclusion) is true. Assuming a claim is true does not serve as evidencefor that claim. This is especially clear in particularly blatant cases: "Xis true. The evidence for this claim is that X is true."

EXAMPLE #1:Bill: "God must exist."Jill: "How do you know."Bill: "Because the Bible says so."Jill: "Why should I believe the Bible?"Bill: "Because the Bible was written by God."EXAMPLE #2:"The belief in God is universal. After all, everyonebelieves in God."EXAMPLE #3:"If such actions were not illegal, then they would not beprohibited by the law."

A fallacy in which “a person asserts that some event mustinevitably follow from another without any argument for theinevitability of the event in question.” In most cases, there are a series of steps or gradations betweenone event and the one in question. Furthermore, no reason is given as to why the intervening steps orgradations will simply be bypassed. This "argument" has the following form:1. Event X has occurred (or will or might occur).2. Therefore event Y will inevitably happen.This sort of "reasoning" is fallacious because there is no reason tobelieve that one event must inevitably follow from another withoutan argument for such a claim.

EXAMPLE #1:We have to stop the tuition increase! The next thing you know, they'll becharging 40,000 a semester!"EXAMPLE #2:"The US shouldn't get involved militarily in other countries. Once thegovernment sends in a few troops, it will then send in thousands to die."EXAMPLE #3:“President Obama’s executive order calls for background checks on peoplewho buy guns. Yeah right! He really wants to take all our guns away anddestroy the Second Amendment!!”EXAMPLE #4:"We've got to stop them from banning pornography. Once they start banningone form of literature, they will never stop. Next thing you know, they will beburning all the books!"

Also known as the “Either/Or” fallacy. A False Dilemma is a fallacy in which a person uses the following pattern of"reasoning":1. Either claim X is true or claim Y is true (when X and Y could both be false).2. Claim Y is false.3. Therefore claim X is true. This line of "reasoning" is fallacious because if both claims could be false, then itcannot be inferred that one is true because the other is false.

EXAMPLE #1:1. Either 1 1 4 or 1 1 12.2. It is not the case that 1 1 4.3. Therefore 1 1 12.EXAMPLE #2:Senator Jill: "We'll have to cut education funding this year."Senator Bill: "Why?"Senator Jill: "Well, either we cut the social programs or we live witha huge deficit and we can't live with the deficit."EXAMPLE #3:"Look, you are going to have to make up your mind. Either youdecide that you agree to abide by the laws in this country or movesomewhere else."

A fallacy in which “an irrelevant topic is presented in order todivert attention from the original issue.” The basic idea is to "win" an argument by leading attention awayfrom the argument and to another topic. This sort of "reasoning" has the following form:1. topic A is under discussion.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.This sort of "reasoning" is fallacious because merely changing thetopic of discussion does not count as an argument against a claim.

EXAMPLE #1:"Argument" against a bond measure for public parks:"We admit that this bond measure for public parks is popular. Butwe also urge you to note that there are so many bond issues onthis ballot that the whole thing is getting ridiculous." (topicswitches from the issue of funding parks to the election and bondmeasures in general)EXAMPLE #2:"Argument" against an equal rights law for homosexuals:"I recommend you don't support the equal right proposition forgays; they're just trying to get special privileges by callingattention to themselves." (topic switches from equal rights togetting special privileges)

From the Latin. Has been traditionally interpreted as "After this,therefore, because of this." A Post Hoc is a fallacy with the following form:1. A occurs before B.2. Therefore A is the cause of B. This fallacy is committed “when it is concluded that one eventcauses another simply because the proposed cause occurredbefore the proposed effect.” The fallacy involves concluding that A causes or caused Bbecause A occurs before B. Yet there is not sufficient evidence toactually warrant such a claim.

EXAMPLE #1: I had been doing pretty poorly this season.Then my girlfriend gave me neon laces for my spikes and Iwon my next three races. If I keep on wearing them I can'thelp but win!EXAMPLE #2: Joan is scratched by a cat while visiting herfriend. Two days later she comes down with a fever. Joanconcludes that the cat's scratch must be the cause of herillness.EXAMPLE #3: The Republicans pass a new tax reform lawthat benefits wealthy Americans. Shortly thereafter theeconomy takes a nose dive. The Democrats claim that the taxreform caused the economic woes and they push to get ridof it.

This fallacy is committed, “when a person draws a conclusion abouta population based on a sample that is not large enough.” It hasthe following form:1. Sample A, which is too small, is taken from population P.2. Conclusion B is drawn about Population P based on Sample A. The fallacy is committed when not enough of a population areobserved to warrant the conclusion. Hasty Generalization, like any fallacy, might have a true conclusion.However, as long as the reasoning is fallacious there is no reason toaccept the conclusion based on that reasoning.

Example #1:Smith, who is from England, decides to attendgraduate school at Ohio State University. He hasnever been to the US before. The day after hearrives, he is walking back from an orientationsession and sees two white (albino) squirrelschasing each other around a tree. In his nextletter home, he tells his family that Americansquirrels are white.Example #2:Sam: “Barry Bonds uses steroids!”Bill: “All those pro athletes are cheating, steroidshooting bums!”

An Appeal to Authority is a fallacy with the followingform:1. Person A is (claimed to be) an authority on subject S.2. Person A makes claim C about subject S.3. Therefore, C is true. This fallacy is committed, “when the person inquestion is not a legitimate authority on thesubject.” More formally, if person A is not qualified to makereliable claims in subject S, then the argument will befallacious.

Please go through your notes and make sure each of the tenfallacies are underlined. Please make sure your name and the title of the lesson isclearly written at the top of the page. Then please gather your notes together and turn them intothe box.