chap003 language and definitions & chap004 fallacies

8/13/2019 Chap003 Language and Definitions & Chap004 Fallacies

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McGraw-Hill/Irwin 2005 The McGraw-Hill Companies, Inc. All rights reserve . 1 - 1


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3Chapter

Introduction toLogic and Critical

Thinking

Language andDefinitions


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Introduction

!i""erent lang#ages$Their varies #ses%"#nctions$ anThe n#m&er o" "orms it ta'es.


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Language Functions (1 of 3)

Ma(or "#nctions%#ses)In"ormative$*+pressive$ an

!irectiveess common "#nctions%#ses)

Ceremonial$er"ormance


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*+amplesMa(or "#nctions%#ses)

In"ormative) the train has eparte /.

*+pressive) that s sweet o" 1o#/.!irective) rive care"#ll1/.

ess common "#nctions%#ses)Ceremonial) how o 1o# o/ 3 wor s ma1 com&ine

e+pressive an other "#nctions.er"ormance) I promise to &e p#nct#al in "#t#re/ 3 wor s

themselves serve to per"orm the "#nction the1 anno#nce$other e+amples I regret/, an I accept 1o#r o""er/ etc.


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4se o" lang#age m#st &e isting#ishe "rom the "orms o"lang#age, which are eclarative, e+clamator1, imperativean interrogative. *+amples)

!eclarative) its hot an h#mi /, A is a isting#ishe st# ent/etc.*+clamator1) oh m1 Go /, that s "antastic/ etc.Imperative) ta'e o"" 1o#r shoes/, change 1o#r note&oo'/ etc.Interrogative) where i 1o# get this "rom /, how i 1o#

re #ce so m#ch weight / etc.ang#age that serves an1one o" the principle "#nctions ma1

ta'e an1 o" the "o#r grammatical "orms.


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Emotive Language, NeutralLanguage, and Disputes

A given sentence or passage can serve several"#nctions 3 that is, "or e+ample, it can e+press "eelingwhile reporting "acts. Th#s a clever #se o" lang#agecan lea to nee less mis#n erstan ings an isp#tes.*motive meaning co#l &e sharpl1 i""erent to the

literal meanings o" some wor s. *+ample)6. me ical vocalar1 ealing with h#man repro #ctive an elimination

is ne#tral, 1et some wor s are ta'en as v#lgar$ there are seven irt1 wor s/that cant &e #se in the 47 me ia.

In logic, we generall1 strive "or lang#age that is, as "aras possi&le, "ree o" istortion that emotive meaning

intro #ce.


8/45 McGraw-Hill/Irwin 2005 The McGraw-Hill Companies, Inc. All rights reserve . 1 - 8

Disputes and Ambiguit

Man1 isp#tes arise #e to an am&ig#o#s #se o"lang#age.!isp#tes "all into three categories)

8&vio#sl1 gen#ine isp#tes$Merel1 ver&al isp#tes$ anApparentl1 ver&al t reall1 gen#ine.

A goo starting point "or those involve withhan ling isp#te resol#tions is to "irst chec' whetherthere is some am&ig#it1 that can &e eliminate &1clari"1ing the alternative meanings in pla1.



Definitions and !"eir #ses



4Chapter


Thinking

Fallacies



$"at is Fallacy?

Fallacies are defects that weaken arguments.

First, fallacious arguments are very, very common and can bequite persuasive, at least to the causal reader or listener. You

can find dozens of examples of fallacious reasoning innewspapers, advertisements, and other sources.

Second, it is sometimes hard to evaluate whether an argumentis fallacious.

n argument might be very weak, somewhat weak, somewhatstrong, or very strong. n argument that has several stages or

parts might have some strong sections and some weak ones.



%lassification of Fallacies (1 of &)

Fallacies of!9elevanc e! where premises are simply not relevant

to the conclusion"

!e"ective in #ction ! where premises, althoughrelevant, are so weak and ineffective that relying onthem is a blunder"

res#mption ! where too much is assumed in the premises" andAm&ig#it1 ! arises from equivocal use of words or

phrases.




:allacies o" relevanc e!#he appeal to populace"#he appeal to emotions $pity etc%"#he red herring! where attention is deliberately deflected away

from the issue under discussion%"#he straw man! in which case position of the opponent is

depicted as being more extreme&unreasonable than is 'ustified bywhat is being asserted"#he attack on person"#he appeal to force" and(issing the point $irrelevant conclusion%




:allacies o" e"ective in #ction !#he argument from ignorance! position held as true or false

merely because it has not been proved otherwise"#he appeal to inappropriate authority" taking the word of an

expert for granted"False cause" and)asty generalization! a single or a few inadequate cases as a

base for applying the conclusion to all or most of the cases.

:allac1 o" pres#mption !ccident"*omplex question" and

+egging the question.



%lassification of Fallacies (' of &)

:allac1 o" pres#mption !ccident" in which generalization is mistakenly

applied to a particular case to which the generalization

does not apply"*omplex question" where question is asked in such a

way as to presuppose the truth of some conclusion buried in that question" and

+egging the question! in which conclusion is stated orassumed in anyone of the premises.



%lassification of Fallacies (& of &)

:allac1 o" am&ig#it1 !quivocation" where two or more meaning of a word

are used, accidently or deliberately, in different parts of

the argument"mphiboly! in which a loose or awkward use of words

can be interpreted in more than one ways"ccent! variation in emphasis in premise$s% and

conclusion"*omposition" and-ivision.



Hasty Generalization

!e"inition ! (aking assumptions about a whole group or range ofcases based on a sample that is inadequate $usually because it isatypical or 'ust too small%.

Stereotypes about people $ frat boys are drunkards, grad students arenerdy, etc.% are a common example of the principle underlying hastygeneralization.

*+ample ! (y roommate said her philosophy class was hard, andthe one /0m in is hard, too. ll philosophy classes must be hard1

#wo people0s experiences are, in this case, not enough on which to base aconclusion.



Missing the Point

!e"inition ! #he premises of an argument do support a particularconclusion22but not the conclusion that the arguer actually draws.

*+ample ! #he seriousness of a punishment should match theseriousness of the crime. 3ight now, the punishment for drunkdriving may simply be a fine. +ut drunk driving is a very seriouscrime that can kill innocent people. So the death penalty should bethe punishment for drunk driving.

#he argument actually supports several conclusions22 #he punishment fordrunk driving should be very serious, in particular22but it doesn0t supportthe claim that the death penalty, specifically, is warranted.



False Cause

#his fallacy gets its name from the 4atin phrase post hoc, ergo propter hoc ,which translates as after this, therefore because of this.

!e"inition ! ssuming that because + comes after , caused +. 5f course, sometimes one event really does cause another one that comes later22for

example, if / register for a class, and my name later appears on the roll, it0s true that

the first event caused the one that came later. +ut sometimes two events that seemrelated in time aren0t really related as cause and event. #hat is, correlation isn0t thesame thing as causation.

*+amples ! 6resident 7ones raised taxes, and then the rate of violent crimewent up. 7ones is responsible for the rise in crime.8

#he increase in taxes might or might not be one factor in the rising crime rates, butthe argument hasn0t shown us that one caused the other.



Appeal to Authority

!e"inition ! 5ften we add strength to our arguments by referringto respected sources or authorities and explaining their positionson the issues we0re discussing.

/f, however, we try to get readers to agree with us simply by impressingthem with a famous name or by appealing to a supposed authority whoreally isn0t much of an expert, we commit the fallacy of appeal to authority.

*+ample ! 9e should abolish the death penalty. (any respected people, such as actor :uy )andsome, have publicly stated theiropposition to it.

9hile :uy )andsome may be an authority on matters having to do withacting, there0s no particular reason why anyone should be moved by his

political opinions22he is probably no more of an authority on the death penalty than the person writing the paper.



Appeal to Emotions Pity!

!e"inition ! #he appeal to pity takes place when an arguer tries to get people toaccept a conclusion by making them feel sorry for someone.

*+ample ! / know the exam is graded based on performance, but you shouldgive me an . (y cat has been sick, my car broke down, and /0ve had a cold, soit was really hard for me to study1

#he conclusion here is You should give me an . +ut the criteria for getting an have to do with learning and applying the material from the course" the principle thearguer wants us to accept $people who have a hard week deserve 0s% is clearlyunacceptable.

*+ample ! /t0s wrong to tax corporations22think of all the money they give to

charity, and of the costs they already pay to run their businesses1



Appeal to Ignorance

!e"inition ! /n the appeal to ignorance, the arguer basically says, 4ook, there0s noconclusive evidence on the issue at hand. #herefore, you should accept my conclusionon this issue.

*+ample ! 6eople have been trying for centuries to prove that :od exists. +ut no onehas yet been able to prove it. #herefore, :od does not exist.

)ere0s an opposing argument that commits the same fallacy!

6eople have been trying for years to prove that :od does not exist. +ut no one has yet been able to prove it. #herefore, :od exists.

/n each case, the arguer tries to use the lack of evidence as support for a positive claim aboutthe truth of a conclusion. #here is one situation in which doing this is not fallacious! /f qualifiedresearchers have used well2thought2out methods to search for something for a long time, theyhaven0t found it, and it0s the kind of thing people ought to be able to find, then the fact that theyhaven0t found it constitutes some evidence that it doesn0t exist.



"tra# Man

!e"inition ! 5ne way of making our own arguments stronger is to anticipateand respond in advance to the arguments that an opponent might make. #hearguer sets up a wimpy version of the opponent;s position and tries to score

point by knocking it down.

*+ample ! Feminists want to ban all pornography and punish everyonewho reads it1 +ut such harsh measures are surely inappropriate, so thefeminists are wrong! porn and its readers should be left in peace.

#he feminist argument is made weak by being overstated22in fact, mostfeminists do not propose an outright ban on porn or any punishment for thosewho merely read it" often, they propose some restrictions on things like child

porn, or propose to allow people who are hurt by porn to sue publishers and producers, not readers, for damages.



$ed Herring

!e"inition ! 6artway through an argument, the arguer goes off on a tangent, raising aside issue that distracts the audience from what0s really at stake. 5ften, the arguer neverreturns to the original issue.

*+ample ! :rading this exam on a curve would be the most fair thing to do. fter all,classes go more smoothly when the students and the professor are getting along well.4et0s try our premise2conclusion outlining to see what0s wrong with this argument!

6remise! *lasses go more smoothly when the students and the professor are getting along well.*onclusion! :rading this exam on a curve would be the most fair thing to do.

9hen we lay it out this way, it0s pretty obvious that the arguer went off on a tangent22the fact that something helps people get along doesn0t necessarily make it more fair"fairness and 'ustice sometimes require us to do things that cause conflict. +ut the

audience may feel like the issue of teachers and students agreeing is important and bedistracted from the fact that the arguer has not given any evidence as to why a curvewould be fair.



%egging the &uestion

!e"inition ! complicated fallacy, an argument that begs the question asks the reader to simplyaccept the conclusion without providing real evidence

the argument either relies on a premise that says the same thing as the conclusion $which you mighthear referred to as being circular or circular reasoning %, or simply ignores an important $butquestionable% assumption that the argument rests on.Sometimes people use the phrase beg the question as a sort of general criticism of arguments, to

mean that an arguer hasn0t given very good reasons for a conclusion, but that0s not the meaning we0regoing to discuss here.

*+amples ! ctive euthanasia is morally acceptable. /t is a decent, ethical thing to helpanother human being escape suffering through death. 4et0s lay this out in premise2conclusionform!

6remise! /t is a decent, ethical thing to help another human being escape suffering through death.*onclusion! ctive euthanasia is morally acceptable.

/f we translate the premise, we0ll see that the arguer has really 'ust said the same thing twice!decent, ethical means pretty much the same thing as morally acceptable, and help anotherhuman being escape suffering through death means active euthanasia. So the premise

basically says, active euthanasia is morally acceptable, 'ust like the conclusion does1 #hearguer hasn0t yet given us any real reasons why euthanasia is acceptable" instead, she has left usasking well, really, why do you think active euthanasia is acceptable< )er argument begs$that is, evades% the real question $think of beg off %.


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E'ui(ocation

!e"inition ! quivocation is sliding between two or more differentmeanings of a single word or phrase that is important to theargument.

*+ample ! :iving money to charity is the right thing to do. Socharities have a right to our money.

#he equivocation here is on the word right ! right can mean bothsomething that is correct or good $as in / got the right answers on the test %and something to which someone has a claim $as in everyone has a right tolife %.Sometimes an arguer will deliberately, sneakily equivocate, often on words

like freedom, 'ustice, rights, and so forth" other times, theequivocation is a mistake or misunderstanding. ither way, it0s importantthat you use the main terms of your argument consistently.

) )


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Can you name this Fallacy?

=% /t is ridiculous to have spent thousands ofdollars to rescue those two whales trapped in therctic ice. 9hy look at all the people trapped in

'obs they don;t like.

3 - ) 33/>:


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?% 6lagiarism is deceitful because it is dishonest.

+ ::/>: #) @A S#/5>


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B% 9ater fluoridation affects the brain. *itywide,student;s test scores began to drop five monthsafter fluoridation began.

65S# )5* $false cause%


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C% / know three redheads who have terribletempers, and since nnabel has red hair, /;ll betshe has a terrible temper too.

) S#Y : > 3 4/D #/5>


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E% Supreme *ourt 7ustice +yron 9hite was an ll2merican football player while in college, so howcan you say that athletes are dumb 3 4/D #/5>


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% 9hy should we put people on trial when weknow they are guilty: #) @A S#/5>


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G% You support capital punishment 'ust because youwant an 8eye for an eye,H but / have several goodreasons to believe that capital punishment is

fundamentally wrongI

S#3 9 ( >


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J% #he meteorologist predicted the wrong amountof rain for (ay. 5bviously the meteorologist isunreliable.

) S#Y : > 3 4/D #/5>


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K% You know 7ane Fonda;s exercise video;s must beworth the money. 4ook at the great shape she;s in.

65S# )5* $false cause%


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=L% 9e have to stop the tuition increase1 #he nextthing you know, they0ll be charging MCL,LLL asemester1

S4/66 3Y S456


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==% #he book Investing for Dummies really helpedme understand my finances better. #he book Chess

for Dummies was written by the same author, was published by the same press, and costs about thesame amount, so it would probably help meunderstand my finances as well.

9 N > 45:Y


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=?% /0m positive that my work will meet yourrequirements. / really need the 'ob since mygrandmother is sick.

66 4 #5 6/#Y


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=B% *rimes of theft and robbery have beenincreasing at an alarming rate lately. #heconclusion is obvious, we must reinstate the death

penalty immediately.

(/SS/>: #) 65/>#


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=C% /0m not a doctor, but / play one on the hit series+imbos and Studmuffins in the 53. You can takeit from me that when you need a fast acting,effective and safe pain killer there is nothing betterthan (orphi-ope ?LLL. #hat is my consideredmedical opinion.

66 4 #5 A#)53/#Y


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4

Chapter


Thinking

Fallacies


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"lippery "lope

!e"inition ! #he arguer claims that a sort of chain reaction, usually endingin some dire consequence, will take place, but there0s really not enoughevidence for that assumption.

#he arguer asserts that if we take even one step onto the slippery slope, wewill end up sliding all the way to the bottom" he or she assumes we can0t stophalfway down the hill.

*+ample ! nimal experimentation reduces our respect for life. /f we don0trespect life, we are likely to be more and more tolerant of violent acts likewar and murder. Soon our society will become a battlefield in whicheveryone constantly fears for their lives. /t will be the end of civilization. #o

prevent this terrible consequence, we should make animal experimentationillegal right now.

Since animal experimentation has been legal for some time and civilization hasnot yet ended, it seems particularly clear that this chain of events won0tnecessarily take place.

Also *no#n as+the Camel,s

-ose


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.ea* Analogy

!e"inition ! (any arguments rely on an analogy between two or more ob'ects,ideas, or situations. /f the two things that are being compared aren0t really alike inthe relevant respects, the analogy is a weak one, and the argument that relies on itcommits the fallacy of weak analogy.

*+ample ! :uns are like hammers22they0re both tools with metal parts that could beused to kill someone. nd yet it would be ridiculous to restrict the purchase of

hammers22so restrictions on purchasing guns are equally ridiculous.9hile guns and hammers do share certain features, these features $having metal parts, being tools, and being potentially useful for violence% are not the ones at stake in decidingwhether to restrict guns. 3ather, we restrict guns because they can easily be used to killlarge numbers of people at a distance. #his is a feature hammers do not share22it0d be hardto kill a crowd with a hammer. #hus, the analogy is weak, and so is the argument based onit.

/f you think about it, you can make an analogy of some kind between almost anytwo things in the world! (y paper is like a mud puddle because they both get

bigger when it rains $/ work more when /0m stuck inside% and they0re both kind ofmurky. So the mere fact that you draw an analogy between two things doesn0t provemuch, by itself.


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False /ichotomy

!e"inition ! /n false dichotomy, the arguer sets up the situation soit looks like there are only two choices. #he arguer then eliminatesone of the choices, so it seems that we are left with only oneoption! the one the arguer wanted us to pick in the first place.

*+ample ! *aldwell )all is in bad shape. ither we tear it downand put up a new building, or we continue to risk students0 safety.5bviously we shouldn0t risk anyone0s safety, so we must tear the

building down.#he argument neglects to mention the possibility that we might repair the building or find some way to protect students from the risks in question22forexample, if only a few rooms are in bad shape, perhaps we shouldn0t holdclasses in those rooms.


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=?% 4ook, you are going to have to make up yourmind. ither you decide that you can afford thisstereo, or you decide you are going to do without

music for a while.

F 4S -/*)5#5(Y $-ilemma%

chap003 language and definitions & chap004 fallacies

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