03-analyzing arguments-basics ver nov 2011

8/3/2019 03-Analyzing Arguments-Basics VER NOV 2011

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Argumentation

Top ic 3

Par

t 1 of2

The

Basics


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Quotes to Ponder

Much that is taught in collegeclasses grows soon out of date,

but the skills of correct reasoning

never become obsolete.

- Irving M. Copi& Carl Cohen


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Do you find hisargumentconvincing?

Why Not?

Hey!! Folks!!ALLsmartpeople drinkXXX!!

I drinkXXXall the time!!I am a smartperson!!

So, do you drinkXXX??


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What is an

Argument


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Argument? Yes&

No.


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Analyzing Arguments

Hisconditionhas gotten

worsesince webled him.

Oh no,well

have tobleedhim

again.

Teenpregnancyis up this

year.

We

need toget rid ofthose sexeducation

classes!You designed

the site, its clearlyyour fault!

I havent sold

a single ice watersnorkeling kit onmy site.

Are You Convinced?Why Not?


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Analyzing Arguments

ArgumentA claim put forward& defendedwithreasons.

Statement / ClaimA sentence that can sensibly be

regardedas eithertrue/false.

Definitions ofImportant Terms:

truefalse

TruthValue


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Examples ofStatements / Claims:

~Redis a color.

~Kuala Lumpuris in Singapore.

~Ghosts do exist.

~Titanicis a bettermovie than Star Wars.

or Youve got tobeJOKING!!


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Statementsare eitherpremisesorconclusions, depending on their

role in an argument.Premises

Statementswhichare used to supportotherstatements.

Conclusion

Statements whichare supportedbyotherstatements.

Crucial elementthatmakesa group ofstatements anargumentis an inference.Aninferenceis supposed to establish

the truth ofconcluding statement.

inference


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Arguments composed of

Analyzing Arguments

Premise (s)

Ar

gum

ent

Premise (s)Statementsclaimedtoprovide evidenceforanother statement, theconclusion.

ConclusionStatementthat thepremises

are claimed to prove/support.

Conclusion


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Three things aboutstatements:

1. 2. 3.

1. A sentence may be used to expressmore than one statement.

Example,

Roses are red& violets are blue.


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2. Notall sentences are statements.

Examples,Where is yourhouse?(Question)

Close yourbook!(Command)

Please submityourassignment.(Request)

Let us study tonight.(Proposal)

InsertyourID into the column.(Instruction)

Oh, my goodness!(Exclamation)

Nonstatements

truefalse

Truth

ValueNonstatementshaveNO


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Some sentences look likenonstatements,are actuallystatements & can be used in

arguments. Here are two examples:

Rhetorical Question

Ought Imperative

Alyssa, you should quit smoking. Dont you

realize how bad that is for your health?

Commencement address: Do not read beautymagazines. They will only make you feel ugly.

(Mary Schmich)


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Exclusions to nonstatements

RhetoricalQuestions OughtImperative&

Rhetorical QuestionsLooks like a questionbutactuallyassertions ofgood/bad.

E.g. Andy, you should quit smoking. Dontyou realize how bad it is for your health?

Assertions something stronglybelieved

statements


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Ought ImperativeLooks like a commandbut actuallyassertions.

E.g. Do not read beauty magazines.They will only make you feel ugly.

(You oughtorshouldnot read.)

Exclusions to nonstatements

RhetoricalQuestions OughtImperative&

statements


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3. Considercontextin which theparticular expression is used.

Example,

Dont cry.might becommandin onecontext&ought imperativein another

context.

Dontcry.

Dontcry.

command ought imperative

Ought imperative: intended to assert a value orought judgmentabout what is good/bador

right/wrong.


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Premises&

conclusions

A

rgu

me

nt


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Premise Conclusion

Put forward as atruth, but whichis not proven.

It is hot in here.

This is a verybeautiful car.

People of this

town are angry.

Statement you wantothers to agree.

Drawnfrompremise (s).

Examples,We need to get out.

You should buy thisbeautiful car.

The factory should be

built elsewhere.


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IdentifyingPremises&Conclusions

Since, for, seeing that,

in view of the fact that,because, given that, as,

as indicated by.

E.g. I would not agreewith you seeing thatyou have made thedecision without my

concern.

Therefore, it follows

that, wherefore, as aresult, suggests that,

thus, consequently, for

this reason, so, whichshows that, that is why,accordingly, we may

infer that, implies that,

hence, proves that.

PremiseIndicators ConclusionIndicators


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IdentifyingPremises &Conclusions

However, beware of these examples!!

I havent seen you sincelast year.

I wouldnt mindseeing thatmovie again.

Sometimes there is no indicator.E.g. Cats are smarter than dogs.

You cant get 8 cats to pull a sled through snow.


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I havent seen you since high school.

Thusfar everything has been great.

It was so cold that even the

ski resorts shut down.There is water on the floorbecause

the sink overflowed.

In noneof these examplesdoes the term in red

function as an indicator word.


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Exercises

2.1 Statement/Non-Statement.

2.2 Identifypremises&

conclusions.


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1. Capital punishment is wrong.

2. Can vegetarians eat animal crackers?3. Ali is the greatest striker in football history.

4. What do you say we stop at the next stop?

5. Lee was the first prime minister of Singapore.

6. Lets party!

7. Great!8. Keep off the grass. (sign)

9. If Sally calls, tell her Im at the library.

10. I hope Peter likes his new job.

2.1 Statement/Non-Statement.

Statement

Non-Statement

Statement

Non-Statement

Statement

Non-Statement

Statement

Non-Statement

Non-Statement

Statement

i l i


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2.2 Identifypremises&conclusions.

1. Since light takes time to reach our

eyes, all that we see really existed inthe past.

2. Life changes when you least expect itto. The future is uncertain. So seizethis day, seize this moment, & makethe most of it.

3. Take care of a good name: for thisshall continue with thee, more than a

thousand treasures precious & great.

i l i


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2.2 Identifypremises&conclusions.3. There is no definitive way to prove any one set of

religious beliefs to the exclusion of all others.For that reason religious freedom is a human right.

4. Science is based on experiment, on a willingness to

challenge old dogma, on an openness to see theuniverse as it really is. Accordingly, sciencesometimes requires courageat the very least thecourage to question the conventional wisdom.

5. Do not play your sound system loudly as you maynot be able to hear warning sirens from emergencyvehicles. In addition, hearing damage from loud

noise is almost undetectable until its too late.


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Class Activity

Make yourownstatements & arguments.

Askother studentsto identifythepremise (s)& the conclusion.

premise conclusion


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2 Types of Arguments

SimpleHas only a single conclusion.

Nosub conclusions.

ComplexContain at least1 sub conclusionto support a single main conclusion.

E.g. This is a beautiful car.You should buy this car.


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2 Types of Arguments

Example of acomplexargument,

We know thateitherA orB committedthe robbery.

ButAcouldnt have committed therobbery because he was in prisonwhen the robbery was committed.

Therefore, B committed the robbery.

Mr. A Mr. B

Robber!!

sub

conclusion


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What is NOTan Argument?

2 conditionsforArguments:

1. A group of2 ormorestatements

&

2. One of those statements

(conclusion) is claimedorintendedto beprovedor

supportedbyothers (premises).


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5 Types:1. Reports

2. Unsupported statementsofbelieforopinion

3. Conditional statements

4. Illustrations

5. Explanations


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REPORT

Name: Susan

Birth: 20 / 06 / 80

Hometown: Muar

Hobby: ReadingAmbition: Doctor

E.g. Susan was born in 1980,in Malaysia. She grew up in

a small town, Muar & .

To conveyinformationabout a subject, not tooffer reasons why onestatement should be

accepted on basis of others.

Reports


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Example (1/2),

Belief: I believe in God.God is the One who created us& we will return to Him

once we die.

Unsupported statements ofbelieforopinion

orAssertion


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Example (2/2),

Opinion: People are not free. Those

who think they are free are hopelesslynave. People are no more able to controltheir own destinies than are ants,& its just anti-scientific to say so.


Unsupported statements ofbelieforopinion


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Examples,

Ifit rains, thenthe picnic

will be cancelled.You must speak French

if you grew up in Quebec.

Bonjour!!

Conditional Statementsif-thenstatements


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Intended to provide examples of a claimrather than toprove orsupportclaim.

Illustrations

Examples,

Many children like to engage in privatespeech. E.g.3 year-old Susan sometimestalk to herself when she plays with her doll.

Illustration: People are not free;just look athow many abusers were abused as a child.


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Try to showsomething is the case,notto prove it is the case.

Explanations

I fell down because thefloorwas slippery

( E x p l a n a t i o n ) . v e r s u s

Example,

Capital punishment should be abolishedbecauseinnocent people may be

mistakenly executed(Argument).

Arguments or


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I speak English because my parents sent meto a boarding school in Kuala Lumpur.

If Ali comes to the party, then Alice will cometo the party.

Explanation

Conditional Statement

Earth was much drier in the distant past

than it is now, & there were large deserts ininland areas. There were no flowering plantsthey evolved much later. The most commontrees were conifers.

Report

Exercise: Arguments orNon arguments

Arguments or


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How can you say that Manchester United is abetter football team than Chelsea? Wake up you

fool! No current English football team is ever betterthan Chelsea, not even Liverpool in the 70s! a fan

The smart school program deserves to besupported with more money. Not only does this

program develop the talents of our students, it alsoleads to more hard-working students. Furthermore,at current funding levels the program cannot beimplemented in many schools. a school teacher

Unsupported statement of belief or opinion

An argument

Exercise: Arguments orNon arguments


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Exercise 2.4

D e t e r m i n e w h i c h o f t h e

f o l l o w i n g p a s s a g e sc o n t a i n arguments & w h i c h do not .

l i


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Evaluating Arguments

To evaluate arguments,ask 2 questions:

1. Are thepremises true?

2. Can thepremisesprovide

good reasonsfor itsconclusion?

l i


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Are thepremises true?

Canpremisesprovidegood reasonsfor its conclusion?

Evaluating Arguments

Evidence

Principle of

RationalAcceptance

Deductivearguments

Inductivearguments

Overview

A P i T ?

To evaluate


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Are the Premises True?

To evaluate, ask2 questions:

1. It is true if it is supportedbyevidence.

2. It uses the Principle ofRational Acceptance.

To evaluate

3 points

R i l A


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Principle ofRational Acceptance

1. The claim does not conflictwithpersonal experience &

observations.Be aware that sometimes

ourinterpretation of ourobservation& experience

is not accurate .

Point

l R i l A


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2. Does the claim conflict withourbackground beliefs?

Background beliefs:network of conscious & unconsciousbeliefs we use as a framework.

Make sure our beliefs are accurate& well grounded. Never believe withoutsufficient evidence &never believe more

strongly than evidence warrants.

Point

i i l R ti l A t


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3. Does a claim come froma crediblesource?

We should accept a claim onauthorityifit comes from a

credible source thatwe haveno good reason to doubt.

Point

i i l R ti l A t


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1. Source is notgenuineexpertorauthority.

2. Source is speakingoutside the area ofhis experience.

Expert?

Good reasons to doubtthecredib i l i ty include:

P i i l R ti l A t


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Good reasons to doubtthecredibilityinclude:

3. The source is biased/ hasmotive to lie ormislead.

4. Accuracyof the sourcespersonal observations orexperiences is doubtful.

P i i l R ti l A t


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Good reasons to doubtthecredibilityinclude:

5. Source is a mediaor internet source thatis generallyunreliable.

6. Claim made by source is in itself,highly implausible/unlikely.

C h P i id

To evaluate


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Can thePremise provideGood Reasonsfor its Conclusions?

2 kinds ofarguments:

DeductiveInductive

All arguments are(categorically) either

Deductive or Inductive


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Deductivearguments try to

prove theirconclusionswith rigorous,

inescapable

logic.

Inductivearguments try to

showtheirconclusions areplausible or

likelygiventhe premise (s).

Deductive Inductive

D d ti I d ti t


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Deductive&Inductive argumentsAllmen are mortal. (premise)

Gandhi was a man. (premise)

Gandhi was mortal. (conclusion)

Deductive argument

Gandhi was Indian. (premise)

MostIndians love curry. (premise)

Gandhi possibly loved curry. (conclusion)

Inductive argument

D d ti A t (1/3)


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Deductive Arguments (1/3)

Attempt to showconclusionsmustbe truegiven thepremises asserted.

Allmammals have hair. Pet Xis a mammal.

Pet

X

Conclusion???

D d ti A t (2/3)


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Example,

1) Allhumans are not perfect.


Yourparents are humans.

Therefore, yourparents

are not perfect.(So love them without condition)

Ded cti e Arg ments (3/3)


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Example,2) If a studentlives in

Regal Park,then he is an MMU student.M

M

U The studentdoes live inRegal Park.

So, he is an MMU student.

Deductive Arguments


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Deductive Arguments

If hes rich, he willorderexpensive wine.

He ISrich.

So, he willorderexpensive wine.

Waiter!!!

Wine year1911 !!!

Inductive Arguments (1/2)


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Simplyclaimthatconclusionsare likelyorprobablegiventhepremises offered.

XYTherefore, it is likelythe next

Malaysian Prime Minister will be a man.

Every previous MalaysianPrime Minister has been a man.

Example,



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Everyrubyso far discoveredhas been red. So,probably

allrubies are red.

AllHarry Potter novels have

been good. Therefore, thenextHarry Potter novelwill

likely be good Key differences (1 2 3)


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Key differences (1,2,3)

Deductive InductiveIfpremises aretrue,then the conclusionmustbe true.

Ifpremises aretrue,then the conclusionis

probablytrue.Conclusion followsnecessarilyfrompremises.

Conclusion followsprobablyfrompremises.

Premisesprovideconclusiveevidencefortruth

of theconclusion.

Premisesprovide good(butnot conclusive)evidencefortruth

of the conclusion.

Key differences (4 5)


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Key differences (4,5)

Deductive Inductive

Impossible for ALL thepremisesto be true&conclusionfalse.

Unlikelythatthepremisesaretrue&conclusionfalse.

Logicallyinconsistentto assertthepremises&denytheconclusion

(if you accept thepremises, then you

mustaccept theconclusion.)

Although logicallyconsistentto assertthe

premises & denythe

conclusion,conclusion is

probablytrueifthe

premises are true.

Conclusion


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Conclusion

A good argumenthas the following:

1. Allthepremises aretrue.

2. Premises provide good reasons toacceptconclusion. Deductivelysound& inductivelycogentargument.

3. Meetstandardsofcritical thinkingdiscussed in Topic 1.Clarity,Precision,

Accuracy, etc

Ded cti e

*Valid: so constructed


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DeductiveArguments

Valid* Invalid

(ALL areunsound)

Sound** Unsound

InductiveArguments

Strong Weak

(ALL areuncogent)

Cogent*** Uncogent

**Sound: having no

defect,sensible, valid.***Cogent: convincingor believable because

it is clear.

that if premises arejointly asserted, theconclusion cannot be

denied withoutcontradiction.

Conclusion


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Conclusion

Good Argumentdoes NOTmean:

Agrees with my viewsPersuasive argumentWell-written orwell-spoken argument

Exercise


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Exercise

Deductive or Inductive?

Common Patterns of


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Common Patternsof

Deductive Reasoning

HypotheticalSyllogismCategoricalSyllogismArgumentbyEliminationArgumentbased on MathematicsArgumentfromDefinition

Hypothetical Syllogism


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HypotheticalSyllogism

Syllogism three-line-argumentthat consists ofexactly2 premises

& aconclusion.

Hypotheticalsyllogism syllogismthat contains at least1 hypothetical

or conditional (if-then) premise

Premise 1 (Major Premise)Premise 2 (Minor Premise)Conclusion



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If then

Logic - conditional elementin aproposition, as

Caesar conquered Gaul,

inIfCaesar conquered Gaul,

he was a great general.

Logic - second memberof aconditional proposition, as

Caesar was a great general

inIf Caesar conquered Gaul,he was a great general.

Conditional Statement / Premise

*Caesar was a great generalif he conquered Gaul.

Antecedent Consequent

Consequent Antecedent




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Example, (1) Modus PonensIfA , thenB.

A. Therefore, B.

IfI want to get the scholarship,

then Id better study hard.I do want to get the scholarship.

Therefore Id better study hard

(fromponere, to

affirm-affirmingtheantecedent)



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Example,

(2) Chain ArgumentChain arguments consists of3 conditional statements linked

together in the following way.

IfA, thenB. IfB, thenC.

Therefore, ifA, thenC.AB

BC



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Example,

(2) Chain Argument

IfI dont study hard now,

I will not pass the subject.IfI dont pass the subject,

Ill be under probation.Therefore, ifI dont study hard

now, Ill be under probation.




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Example, (3) Modus Tollens(Denying theconsequent)

IfA , thenB.NotB. Therefore, notA.

If were in FOSEE, then were inMelaka. Were notin Melaka.

Therefore were not in FOSEE



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Example, (4) Denying theAntecedent

If you are the one who sends thoseflowers, you are a lovely person.

You are notthe one whosends me those flowers.

IfA , thenB.

NotA. Therefore, notB.

Therefore, you are not a lovely person.

Notreliable!!



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Example,

(5) Affirming theConsequent

If it is a banana, it is afruit.

It is afruit.

IfA , thenB.

B. Therefore,A.

Notreliable!!

Therefore, it is a banana.

Categorical Syllogism (1/2)


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CategoricalSyllogism (1/2)

Three-line argumentin whicheach statement begins with thewordAll, SomeorNo.

Example (1/3),

Allwhalesaremammals.Allmammalsare animals.

So, allwhalesareanimals.

whale

gorilla

lion

cow

Categorical Syllogism (2/2)


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CategoricalSyllogism (2/2)

Example (2/3),Allbatsarenocturnal animals.Nosalamandersarenocturnal animals.

Nosalamandersarebats.

Example (3/3),

Notennis playersareshort.Someadultsareshort.

Some adults are not tennis players

Argument by Elimination


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Argumentby Elimination

Seeks to logicallyrule outvarious possibilitiesuntil onlyasingle possibilityremains.

Therefore she went to class

But Susan did notgo to the library.

EitherSusan went to the

libraryorshe went to class.Example,

Argument based on


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Argumentbased on

Mathematics

Example,

Lighttravels at a rate of186,000 miles per second.

The sun is more than 93 million

miles distant from the earth.Therefore, it takes more than

eight minutesfor the suns light

to reach the earth.

93

millionm

iles

Math

Argument from Definition


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Argument from Definition

The conclusion is presentedas being truebydefinition.

Therefore, he is a doctor.

Peter is apediatrician.

Example,Pediatrician=doctor

Common Patterns of


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Common Patterns ofInductive Reasoning

Six common patterns,

Inductive generalization

Predictive argument

Argument from authority

Causal argument Statistical argument

Argument from analogy

Inductive Generalization (1/2)


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An argumentin which a generalizationis claimedto beprobably truebased on information about somemembers

of aparticular class. All, most.

Example,

Ive met 4Japanese people, & theywere hardworking. Therefore,probably,

most Japanese people are hardworking

Konnichiwa!!!



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Example,

All dinosaur bones so far discoveredhave been more than 65 million years old.

Therefore,

probably

ALL dinosaur bonesare more than65 million years old.


Predictive Argument


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Predictive Argument

Ap red ic t ion that isdefended with reasons .

Therefore,probably,

she will come late today

Example,

Amyalways

come late to class.

Must

hurry!!!

Argument from Authority


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Argument from Authority

Asserts a claim & then supports claimby citing somepresumed authorityorwitnesswho has said claim is true.

Therefore,probablythereis

a ghoston the

23rdfloor

Example,

My friend told me thathe

saw a ghoston the 23rdfloor.

Causal Argument


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Causal Argument

Assertsordenies that something isthe cause of something else.

Examples,

I cant log in the MMLS.The serverisprobablydown.

Rashid isnt allergic to peanuts.I saw him eat a bag of peanutson the flight from Langkawi.

Statistical Argument


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Statistical Argument

Example,

70% ofMMU studentsdrive to the campus.

Rosie is an MMU student.Most probably, shedrives to the campus.

Rests on statisticalevidence.

Air-Rosie

Argument from Analogy


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Argument from Analogy

Conclusion is claimed todepend on analogy(a comparisonofsimilarity)

between 2 or more things.

Basic logical pattern: These things are

similarin such-and-such ways.Therefore, theyreprobablysimilarin somefurther way.

Analogy


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~Aliis a graduate ofMMU University,& he is bright, assertive &polite.

~Mayis a graduate ofMMU University,& she is bright, assertive, &polite.

~Venu is a graduate ofMMU University.~ Therefore, most likely(orprobably),

Venu is bright, assertive, &polite.

Example, Ali May Venu

a ogy

Deductive


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Deductive

Validity

Inductive Strength

versus

Deductive

*Valid: so constructedthat if premises are


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DeductiveArguments

Valid* Invalid

(ALL areunsound)

Sound** Unsound

InductiveArguments

Strong Weak

(ALL areuncogent)

Cogent*** Uncogent

**Sound: having no


it is clear.

that if premises arejointly asserted, theconclusion cannot be



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DeductiveValidity

Valid?Invalid?

Validdoes notmean true.Validmeans that the argument

is well reasoned

Deductive Validity


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Deductive Validity

Validdeductive argument:logical ly rel iable

deductive argument(The conclusion really doesfollow

necessarilyfrom thepremises).

Premises ConclusionLeads to

Deductive Validity


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3 conditions:1. Ifpremisesare true,

conclusionmust be true.

2. The conclusionfollowsnecessarilyfrom thepremises.

3. It is impossible to assertallthepremises as true & deny

the conclusion

Deductive Validity

Deductive Validity


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educt e a d ty

Valid arguments can:1. Have obviouslyfalsepremises,

&false conclusion.

Example,

Allsquares are circles.Allcircles are triangles.

Therefore all squares are triangles

squares

triangles

circles

Deductive Validity


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2. Havefalsepremises,& a trueconclusion.

y

Example,Allfruits are vegetables.Caulifloweris afruit.

Therefore, caulifloweris a vegetable . cauliflower

Deductive Validity


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3. Have truepremises,& trueconclusions.

Example,If youre reading this, you are alive.

y

Therefore, youre alive.Youre reading this.

Deductive Validity


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However, valid arguments

y

All truepremises

FalseConclusion

CANNOT

CANNOThaveALL true premises,

& afalseconclusion.

Deductive Validity


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Invaliddeductive argument:the conclusiondoes not follow

necessarilyfrom thepremises.

y

Denying theantecedent,Affirming theconsequent.

Examples,

Notreliable!!

Denying the Antecedent Notli bl !!


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Argument of following form isinvalid:IfAthenB.NotA, therefore, NotB.

If youre hit by a car when youre 6 then youll dieyoung. But you were nothit by a car when you

were 6. Thus, you willnotdie young.

Example,

or or or

reliable!!

(Of course, you could be hit by a train or apianoor

at any other age after six or die of other causes!!)

Affirming the Consequent

Notli bl !!


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Argument of following form isinvalid:IfAthenB,Btherefore,A.

(Of course, even though thepremises are true,I might be in Johor, or any other state in Malaysia.)

If I am in Melaka, then I am in Malaysia.I am in Malaysia, thus, I am in Melaka.

Examples A B

If the factory is polluting the riverthen we see an increase in fish deaths.

And fish deaths have increased.Thus, the factory is polluting the river. x

x

reliable!!

Deductive Validity


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CONCLUSION

Validdoesnt mean good

ortrue argument.Validmeans argument is

well-reasoned,has a logically reliable

pattern of reasoning

y

Deductive

*Valid: so constructedthat if premises are


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Arguments

Valid* Invalid

(ALL areunsound)

Sound** Unsound

InductiveArguments

Strong Weak

(ALL areuncogent)

Cogent*** Uncogent

**Sound: having no


it is clear.

f pjointly asserted, theconclusion cannot be


Deductive Validity


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Ifargument is valid+premisestrue

y

Invalid, or have at least1false

premise, orboth

(good argument).

(bad argument)

unsounddeductive argument

sounddeductive argument

Quotes to Ponder


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Validdeductive argumentsare like steel traps.Once a person walks into the

trap by accepting thepremises,

there is no escape; the

conclusion follows necessarily.- Kathleen

Dean Moore

Q


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Inductive Strength

Weak

Strong

Inductive Strength


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Strong inductive argument:conclusion followsprobably

from thepremises.

Example,

Most models are thin & slim.Susan is a model.

Probably, she is thin & slim.

g

Inductive Strength


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Weak Inductive argument:the conclusionis notprobably

true even if thepremises are true.Example,

All Malaysian PM has been a man.Therefore, probably, the next

Malaysian PM will be a woman

g

Inductive Strength


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Strong inductive argumentcan:1. havefalsepremises, & a

probablyfalse conclusion.2. have truepremises, & a

probablytrueconclusion.

3. havefalsepremises, & aprobablytrueconclusion.

Inductive Strength


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Strong inductive argumentCANNOT??

have truepremises, & a

probablyfalseconclusion.

DeductiveA t

*Valid: so constructedthat if premises arej i tl t d th


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Arguments

Valid* Invalid

(ALL areunsound)

Sound** Unsound

InductiveArguments

Strong Weak

(ALL areuncogent)

Cogent*** Uncogent

**Sound: having no


it is clear.

jointly asserted, theconclusion cannot be


Inductive Strength


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Strong inductive argument+true premises

(good argument)Weak, or has atleast 1false premise

or both

cogentargument

uncogentargument(bad argument)

Quotes to Ponder


110/110

TheAimofArgument,or discussion,shouldnotbe victory,

butprogress.

- Joseph Joubert

03-analyzing arguments-basics ver nov 2011

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