Introduction to Philosophy EXAM 1

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A r g u m e n t s 2

INFORMAL FALLACIES AND OTHER MUNDANE

POINTS ABOUT LOGIC

¡ Before introducing and discussing informal fallacies (the main subject of this lecture), we’ll need a definition of fallacies more generally.

¡ Fir st, let’s star t with a basic definition: A fallacy is an error in reasoning that tends to be psychologically per suasive.

¡ As we learned last time, once we have determined that there is an argument, and then determined what the conclusion is and what the premises are, then we can evaluate the argument. This can sometimes be quite easy like in Ex. 1 and 2 below:

INTRODUCTION

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¡ Ex 1 . Two plus two equals four. So, the Miami Heat will win the NBA Championship.

§ Or

¡ Ex 2. Denver was the last dinosaur. John likes dinosaurs. So, John must have destroyed all the unicorns.

INTRODUCTION

¡ But when an argument is not so easy to evaluate then it is impor tant (and helpful, generally) to know that arguments can go wrong in one of two ways:

§ Logical form is bad

§ Premises are false (something about the content not the structure)

¡ Informal fallacies are instances of both these problems!

INTRODUCTION

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¡ Indeed! Even if the logic is per fect, if the premises are false – any of them – then we are not rationally compelled to think that the conclusion is true. This need not force the per son who constructs the argument to give up. It might be possible (and likely it is entirely plausible) to reconstruct the argument in such a way as to not need the faulty premise. It will be an impor tant tool for you when you evaluate arguments to be able to determine if any given premise of an argument is false. It is ver y common to encounter arguments that make error s (logical or substantive). Many such faulty arguments look power ful, though, and we need to be ver y careful about them.

INTRODUCTION

¡ First, some points about Formal fallacies.

§ You remember that fallacies are _________(?)

§ For the most part, we are going to be interested in informal fallacies but I would quickly like to look at Formal Fallacies.

§ Ex 3. If nepotism is wrong, then it is destructive. And it is destructive. So, nepotism is wrong. §  This is an instance of the formal fallacy called “Af firming the

Consequent”. §  Bowel movement example.

FORMAL FALLACIES

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¡  Ex 4 . If g ood inte nt ions m ake g ood s e rm ons , t he n Reve re nd McGuire is a good pre ac he r. Unfor t unate ly, t hey don’t , so he ’s not .

§  This is an instance of the formal fallacy called “Denying the Antecedent”.

¡  Ex 5 . All cant aloupe s are m e lons . All wate rm e lons are m e lons . S o, all wate rm e lons are cant aloupe s .

§  This is an instance of the formal fallacy called “The Undistributed Middle”.

¡  T h e s e will be as m uc h as you ne e d to k now for t h e cour s e . If you care to know more t he n he ad ove r to Rat ionalW iki or about .com ’s pag e on arg um e nt s .

FORMAL FALLACIES

¡  It is im por t ant to g et s om e bas ics about arg um e nt s out of t he way before moving for ward with in formal fal l aci es. T he fir st t h ing I’d like to dis cus s is s om e not s o f ar-fet c h e d rule s of e ng ag e m e nt ( T H E P RINC IP LES , bro! ) :

¡  P rinc iple 1 – Ide nt if y t h e pre m is e s and t h e c o nc lus io n. ¡  P 2 – Elim inate exc e s s ve rbiag e . ¡  P 3 – Em ploy unifo rm lang uag e . ¡  P 4 – B e f air and c h arit able in inte rpret ing an arg um e nt . ¡  P 5 – D o not c o nf us e s ubc o nc lus io ns w it h t h e final c o nc lus io n.

§ These will help you engage better (more fruitfully and honestly) with your fellow interlocutor.

A METHODOLOGICAL AND TERMINOLOGICAL ASIDE

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¡  T h e s e can be put into broade r cate g orie s , wh ic h s h ould h e lp in re m e m be ring and unde r s t anding t h e m .

¡  Fallacies of Relevance

¡  Ad hominem ("Argument against the man" from Latin): Such arguments attempt to disprove another argument by undermining the integrity of the person making the argument. In this case, one critiques the person rather than the belief itself, or the argument itself. Often, this strategy makes an appeal to the reader based on some bias of the person making the argument.

INFORMAL FALLACIES

§  Ex XX. Bob’s argument against abortion cannot be believed, because Bob is a committed Catholic, and he’s biased in favor of pro-life.

§  Ex XX. Jones argues for vegetarianism. He says it is wrong to kill animals unless you really need them for food, and that, as a matter of fact, nearly everyone can get enough food without eating meat. But Jones is just a nerdy intellectual. So, we can safely conclude that vegetarianism remains what it has always been—nonsense!

§  EX. XX. This theory about a new cure for cancer has been introduced by a women known for her Marxist sympathies. We shouldn’t listen to her ideas because egalitarians are all socialist assholes.

INFORMAL FALLACIES

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¡  Ad hominem ¡  Ex. XX.

INFORMAL FALLACIES

¡  A last note on Ad H o m inum :

§ Only if we can show that someone’s character somehow makes the claim dubious are we justified in rejecting the claim because of a individual's personality. Though such a circumstance is rare, not all appeals to character are irrelevant. When might it be relevant? When the circumstance of the person in question pertains to his/her qualifications to be a legitimate authority on the matter. When the character of the person in question is in question with respect to something known about him/her specifically regarding the present deliberation.

INFORMAL FALLACIES

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¡  Tu Q u o q u e ( " Yo u , a l s o " o r " Yo u ' r e a n ot h e r " , f ro m L a t i n ) : T h i s i s a fo r m o f t h e a d h o m i n e m . O f te n a p e r s o n w i l l d i s m i s s s o m e b e l i e f o r a r g u m e n t f ro m a n ot h e r p e r s o n b e c a u s e t h a t ot h e r p e r s o n d o e s n ot a c t c o n s i s te n t l y w i t h t h e b e l i e f t h ey r e c o m m e n d . I n s h o r t , w h et h e r o r n ot a p e r s o n i s a hy p o c r i te i s i r r e l eva n t r e g a r d i n g t h e t r u t h o f t h e i r c l a i m .

§  Ex 10. Dad tells me I should not lie. He says lying is wrong because it makes people stop trusting one another. But I’ve heard my Dad lie. Sometimes he calls in “sick” to work when he isn’t really sick . So, lying isn’t actually wrong—Dad just doesn’t like it when I lie.

§  Ex 11 . Bin Laden and U.S. sponsored terrorism.

§  EX. XX. If you think communal living is the way to go, then why aren’t you living in a kibbutz!

§  EX. XX. German Chancellor's outrage over being wiretapped.

INFORMAL FALLACIES

¡  Ad B aculum Fallacy ( Appe al to Force ) : These sor ts of arg um e nt s involve de fe nding / jus t ifying t h e conclus ion by a t h re at to t h e we ll-be ing of t hose who do not acce pt it . T he t h re at m ay be im plicit or ex plic it .

§  Ex 12. Mr. Jones you helped us impor t the drugs. For this, the Boss is grateful. But now you say you’re entitled to 50 percent of the profits. The Boss says you’re entitled to 10 percent. Unless you see things the Boss’s way, you’re going to have a ver y nasty accident. So, you’re entitled to 10 percent. Got it?

§  Ex 13. Lately, there has been a lot of negative criticism of our policy on dental benefits. Let me tell you something, people. If you want to keep working here, you need to understand that our policy is fair and reasonable. I won’t have anybody working here who thinks our policy is unfair or unreasonable.

INFORMAL FALLACIES

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¡  Ad Po p u l u m ( A p p e a l to t h e Pe o p l e ) : i s a n a t te m p t to p e r s u a d e a p e r s o n ( o r g ro u p ) by a p p e a l i n g to t h e d e s i r e to b e a c c e p te d o r va l u e d by ot h e r s . Po l i t i c i a n s o f te n d o t h i s a t p o l i t i c a l r a l l i e s by p u m p i n g u p a c row d a n d m a k i n g t h o s e i n d i v i d u a l s w i t h i n t h e c row d ( b e c a u s e o f t h e i r d e s i r e to b e p a r t o f t h e g ro u p ) fe e l l i ke h i s / h e r p o i n t i s m o r e p e r s u a s i ve b e c a u s e t h ey a r e a m o n g s t a c h e e r i n g c row d , l i ke i n t h e exa m p l e b e l ow.

§  Ex 14. I look at you all, and I tell you, I am proud to be here. Proud to belong to a par ty that stands for what is good for America. Proud to cast my lot with the kind of people who make this nation great. Proud to stand with men and women who can get our nation back on its feet. Yes, there are those who criticize us, who label our view of trade agreements as “protectionist”. But when I look at you hard-working people, I know we’re right, and the critics are wrong (-the crowd cheers!-).

§  Ex 15. Ms. Riley, are you saying that President Bush made a moral error when he decided to go to war with Iraq? I can’t believe my ears. That’s not how Americans feel. Not true Americans, anyway. You are an American, aren’t you, Ms. Riley?

INFORMAL FALLACIES

¡  Re d H e rring : T he raising of an irre levant issue during an arg um e nt . T h is is one of t h e favorite te c h nique s of polit ical s pin do c to r s . It us ually c o m e s into play w h e n s o m e o ne want s to c o nv inc e yo u t h at t h e o ppo ne nt ’s po s it io n is w ro ng .

§  Ex. XX. “Ever y woman ought to have the right to abor tion. All those pro-lifers obstruct the entrance of clinics, get in women’s faces, and threaten doctors.”

§  All of this may be true, but no matter because the behavior of the pro-lifers has absolutely no relevance to whether or not women should have a right to abortion.

INFORMAL FALLACIES

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¡ Ad Misericordiam (Appeal to Pity) ¡ Is an argument mean to win someone over by playing with their

emotions (namely, sympathy or pity). ¡  E x . X X . J i l l : " H e ' d b e a te r r i b l e c o a c h fo r t h e te a m . "

Bill: "He had his hear t set on the job, and it would break if he didn't get it." J i l l : " I g u e s s h e ' l l d o a n a d e q u a te j o b . ”

¡  E x . X X . " I ' m p o s i t i ve t h a t my wo rk w i l l m e et yo u r r e q u i r e m e n t s . I

r e a l l y n e e d t h e j o b s i n c e my g r a n d m ot h e r i s s i c k ”

¡  E x . X X . " I s h o u l d r e c e i ve a n ' A ' i n t h i s c l a s s . A f te r a l l , i f I d o n ' t g et a n ' A ' I wo n ' t g et t h e fe l l ow s h i p t h a t I wa n t . "

INFORMAL FALLACIES

¡  Fallacies involving insuf ficient evidence

¡  Appeal to I gnorance : W he n some one use s a lac k of k nowle dge as a jum ping of f point for t h e ir own ot h e r wis e unfounde d s pe c ulat io ns . It do e s not fo llow t h at , s im ply be c aus e we h ave not confirm e d t h at s om et h ing is t rue , t h at it is fals e , nor doe s it follow t hat , s im ply be caus e we have n’t s hown t hat s o m et h ing is f als e , t h at it is t rue ( o r wo r t hy o f be lie f ) .

§  Ex 16. After Centuries of tr ying, no one has been able to prove that reincarnation occurs. So, at this point, I think we can safely say conclude that reincarnation does not occur.

§  Ex 17. Evolution and the God of the gaps.

INFORMAL FALLACIES

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¡ False Cause Fallacy § occurs when one cites to sequential events as evidence

that the first caused the second.

§  Ex. XX. Obama is a terrible president because he is black.

§  Ex. XX. Ever y day, I eat cereal for breakfast. One time, I had a muf fin instead, and there was a major ear thquake in my city. I've eaten cereal ever since.

§  Ex. XX. "Defense attorney Ellis Rubin claims Ronald Zamora's constant exposure to T V crime shows such as re-runs of 'Kojak' and 'Police Woman' was responsible for 'diseasing his mind and impairing his behavior controls.' 'Without the influence of television ... there would not have been any crime,' Rubin argued."

INFORMAL FALLACIES

¡ False Cause Fallacy §  Ex. XX.

INFORMAL FALLACIES

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¡  Fa l l a c i e s i nvo l v i n g a m b i g u i t y ¡  E q u i vo c a t i o n Fa l l a c y: I t o c c u r s w h e n t wo ( o r m o r e ) m e a n i n g s o f a

wo r d ( o r p h r a s e ) a r e u s e d i n a c o n tex t i n w h i c h va l i d i t y r e q u i r e s a s i n g l e m e a n i n g .

¡  Ex 19. I agree with Christians in their claims that God is love. But unlike Christians, I’m not afraid to draw the obvious logical consequence: Love is God.

¡  Ex XX. The priest told me I should have faith. I have faith that my son will do well in school this year. Therefore, the priest should be happy with me.

¡  Ex XX. Why should you question the Theor y of Evolution? Because it's called the 'theor y of evolution', so evolution is an unproven assumption!

¡  Ex.XX. The elements of the moral argument on the status of unborn life… strongly favor the conclusion that this unborn segment of humanity has a right not to be killed, at least. Without laying out all the evidence here, it is fair to conclude from medicine that the humanity of the life growing in a mother's womb is undeniable and, in itself, a power ful reason for treating the unborn with respect.

INFORMAL FALLACIES

¡  C o m po s it io n : T his is t he flipside of t he be low ( Div ision) . Just be caus e s om et hing is t rue of t he m e m be r s of a g roup ( e g , pos s e s s s om e t rait ) , it doe s not follow t hat t he g roup as a whole posse sse s t hat t rait . T he se come in t wo forms

¡  Par t - W h o le ¡ Ex 21 . Ever y par t of that car is light, therefore the car is light.

¡ Ex 22. The atoms that make up the body are invisible (to the naked eye), therefore the body should be invisible (to the naked eye).

¡  Me mbe r s-Group

¡ Ex 24. Elephants eat more than humans. So, elephants as a group eat more than humans as a group.

INFORMAL FALLACIES

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¡  Div ision: It is a mist ake to t hink t hat be cause somet hing is t rue of a wh ole it is als o t rue of it s par t s . S im ilarly, one e rr s whe n t hinking t hat , ne ce ssarily, if somet hing is t rue of a group of pe ople it is t rue of e ac h me mbe r of t he group.

§  Ex 25. The Senate committee on Intelligence is a ver y influential group in Washington. Jim is on that committee, and is thus ver y influential in Washington.

§  Ex 26. Einstein’s brain is more ef fective than my brain, thus the cells that make up Einstein’s brain are more ef fective than the cells that make up my brain.

INFORMAL FALLACIES

¡  Fallacies involving unwarrante d pre m is e s

¡  Petitio P rinc ipii ( B e g g ing t h e Que s t ion) : T his occur s whe n t he conclusion is use d somewhe re as a pre mise in t he argume nt .

§  Ex 27. The Bible says that God exists. The Bible is true because God wrote it. Therefore, God exists.

§  Ex XX. If it’s on T V, it has to be a good show, because only good shows get on T V.

§  Ex. XX. John: "Why didn't you include Lorena's poetr y in the student publication?"  Anne: "Because it was judged as not suf ficiently wor thy of publication."

INFORMAL FALLACIES

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¡  Quic k as ide on t he us e of “ be g g ing t he que s t ion” :

§ The phrase “beg the question” is frequently misused. You might hear someone say, “And that statistic begs the following question …” No! It might prompt the question, it might raise the question, but it does not beg the question. You can’t have the conclusion also be one of the premises, otherwise the whole notion of an argument (when one claim is used to support some other claim) makes no sense. To put it another way, the formal expression of this fallacy is: P is untrue because P is untrue.

INFORMAL FALLACIES

¡  Fa l s e D i l e m m a : We f r e q u e n t l y r e a d a n d h e a r t h a t o n e m u s t p i c k a s i d e , o n e m u s t s t a n d fo r o r a g a i n s t s o m et h i n g . I n m o s t c a s e s , t h e r e a r e m o r e t h a n j u s t t wo a l te r n a t i ve s o r p o s s i b i l i t i e s . B u t t h e p e r s o n w h o m a ke s t h e f a l s e d i l e m m a t r i e s to fo rc e yo u to a g r e e w i t h h i s s i d e , s i n c e i f yo u d o n ’ t t h a t wo u l d m a ke yo u l o o k e i t h e r l i ke a n i d i ot o r i m m o r a l .

§  Ex 28. You either go to college and make something of yourself or you fail at life with no chance of making good money and living a good life.

§  Ex 29. “You’re either for us or against us.” You’re either a patriot or a traitor.” “Either we have to fight an all out militar y war against the countries that suppor t terrorists or we must die as spineless victims.”

§  Ex. XX. Good students will study and learn without the threat of an exam, and bad students won't study and learn even with the threat of an exam. So, exams ser ve no purpose

INFORMAL FALLACIES

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¡  S l i p p e r y S l o p e : T h i s i s a c o n c l u s i o n b a s e d o n t h e p r e m i s e t h a t i f A h a p p e n s , t h e n e v e n t u a l l y t h r o u g h a s e r i e s o f s m a l l s t e p s , t h r o u g h B , C , . . . , X , Y, Z w i l l h a p p e n , t o o , b a s i c a l l y e q u a t i n g A a n d Z . S o , i f w e d o n ' t w a n t Z t o o c c u r, A m u s t n o t b e a l l o w e d t o o c c u r e i t h e r. T h e s e a r e g i v e n w i t h o u t c i t i n g m u c h e v i d e n c e .

¡  E x . X X . T h e r u l i n g s e e m s l i k e t h e b e g i n n i n g o f a t o t a l i t a r i a n s t a t e . J u d g e O w e n s i s v i o l a t i n g t h e c o n c e p t o f t h e s e c r e t b a l l o t b y d e m a n d i n g t h a t f a c u l t y m e m b e r s r e v e a l h o w t h e y v o t e d . N e x t t h e g o v e r n m e n t w i l l w a n t t o p r o h i b i t s e c r e t v o t i n g i n u n i o n s , p r o f e s s i o n a l o r g a n i z a t i o n s , c o r p o r a t i o n s , a n d f i n a l l y i n t h e g e n e r a l e l e c t i o n .

¡  E x . X X I f w e b a n H u m m e r s b e c a u s e t h e y a r e b a d f o r t h e e n v i r o n m e n t e v e n t u a l l y t h e g o v e r n m e n t w i l l b a n a l l c a r s , s o w e s h o u l d n o t b a n H u m m e r s .

¡  E X . X X ( 1 ) I f y o u b u y a G r e e n D a y a l b u m , t h e n n e x t y o u ’ l l b e b u y i n g B u z z c o c k s a l b u m s , a n d b e f o r e y o u k n o w i t y o u ’ l l b e a p u n k w i t h g r e e n h a i r a n d e v e r y t h i n g . Yo u d o n ’ t w a n t t o b e c o m e a p u n k . S o , y o u s h o u l d n ’ t b u y a G r e e n D a y a l b u m .

INFORMAL FALLACIES

§ Straw Man: Such arguments are direct responses to an opposing position. Straw man arguments distor t their opposition, changing their meaning, distor ting them in such a way as to make it ver y easy to topple them. In this case, one makes dif fering opinions look like they suppor t positions which

§ (i) are easy to disprove, and

§ (ii) are not in fact the position of the opposition.

INFORMAL FALLACIES

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¡  Ex XX. Jim says: I think that some of the poor ought to receive limited public assistance in the form of housing and job training. Bob responds: Your position is ultimately communist, which was shown to be a failure in the economic failure of the Soviet Union and the rest of Eastern Europe.

¡  Ex XX. Susan advocates the legalization of cocaine. But I cannot agree with any position based on the assumption that cocaine is bad for you and that a society of drug addicts can’t flourish. So, I disagree with Susan.

¡  S e e h ow t h is v iolate s principle 4 above ? ! ? !

INFORMAL FALLACIES

¡  EX . X X . From a draf t of a bill ( H C R 74 ) cons ide re d by t he Louis iana St ate Le g is lat ure in 2 0 01 :[ 7 ] W h e re as , t h e writ ing s of Charle s Dar win, t he fat he r of evolut ion, promote d t he jus t ificat ion of racis m , and his book s On t he Orig in of S pe cie s and T h e De s ce nt of Man pos t ulate a h ie rarc hy of s upe rior and infe rior race s . . . . T he re fore , be it re s olve d t hat t he le g is lat ure of Louisiana doe s he re by de plore all inst ance s and all ide olog ie s of racis m , doe s he re by re je ct t he core conce pt s of Dar winist ide ology t hat ce r t ain race s and classe s of humans are inh e re nt ly s upe rior to ot h e r s , and doe s h e re by conde m n t h e ex te nt to wh ic h t h e s e ph ilos oph ie s h ave be e n us e d to jus t ify and approve racis t pract ice s .

INFORMAL FALLACIES