limits of logic in politics slides - No Access, Magellan. Mark Bauer Department of Philosophy Center...

Post on 19-Mar-2018

223 views 5 download

Transcript of limits of logic in politics slides - No Access, Magellan. Mark Bauer Department of Philosophy Center...

Dr.MarkBauerDepartmentofPhilosophy

CenterforBioethicsandHumanitiesUniversityofColoradoDenver|AnschutzMedicalCenter

TheLimitsofLogicinPolitics

ReasoningasskilledactivityReasoningisactivity.

Itisaskilledactivity.

Itcanbebetterorworse……justasspeakingSpanish,playingpiano,orpullinga720.

“Better”,”worse”,“correct”,“incorrect”,“right”,and“wrong”,etc.presupposestandards.

Validity:- theconclusionmust betrueifthepremisesare- itisimpossible forthepremisestobetrueandtheconclusionfalse.

Invalidity:- theconclusionneednotbetrueifthepremisesare.- itispossiblefortheconclusiontobefalseevenifthepremisesaretrue.

Tworelatedwaystogowrong:1) Evidencefailstoexcludealternative

conclusions2) Evidenceisirrelevanttotheexclusionof

alternatives.Validity:thesingle

standardoflogic

PossibilitySpace

Paris

Seattle

NewYork

Denver

Add some facts: 1) Bob is in thewestern U.S.; and 2) Bob can seethe ocean.

Valid Inference: Bob is in Seattle.

PossibilitySpace

Paris

Seattle

NewYork

Denver

Add one fact: Bob is in the westernU.S.

Invalid inference: Bob is in Seattle.

Validity:- theconclusionmust betrueifthepremisesare-itisimpossible forthepremisestobetrueandtheconclusionfalse.

Invalidity:- theconclusionneednotbetrueifthepremisesare.- itispossiblefortheconclusiontobefalseevenifthepremisesaretrue.

Fragilitypointsincorehumanreasoning

• Groundfloorcognitiveprocessing• Emotiveoverrides• Base-linehumanlearningsystem• Communicativebandwidthlimits

TheGroundFloor:ConditionalsandDisjunction

Conditionals• Aconditionalisastatementcomposedofatleasttwocomponentstatementsinwhichthetruthofoneisconditionedontheother.

• Thatis,theseare“If…then…”sentences.• Theconditionalreflectsourbasicunderstandingforhowthingshangtogether.

• Initsdisguisedformintheuniversal,itreflectsourcategoricalknowledge.• “AllA’sareB’s”isequivalentto“IfxisA,thenx

isB”

• Itiswhatmakesourknowledgeactionable,knowing“BifA”allowsustobringaboutBbywayofAorblockAbyblockingB.

Disjunctions• Adisjunctionisastatementcomposedofatleasttwocomponentstatementsinwhichatleastonecomponentmustbetrueforthewholestatementtobetrue.

• Thatis,theseare“…or…”sentences.• Thedisjunctionreflectsthebasiccapacitytoconsideralternatives.

• Withoutthepossibilitytoformulate,consider,andevaluatealternatives,thereissimplynoproblem-solvingcapacities.

CorrectandIncorrectConditionalandDisjunctiveProcessing

ValidIfP,thenQ.P.So,Q

IfMaryisalive,thenthereisoxygen.Maryisalive.So,thereisoxygen.

IfP,thenQ.Not-Q.So,not-P.BobishereifJoeis.Bobisn’there.So,Joeisn’t.

IfP,thenQ.So,ifnot-Q,thennot-P.Iftherosesareblooming,thentheaphidsareout.So,iftheaphidsaren’tout,thentherosesaren’tblooming.

OnlyPorQ.Not-P.So,Q.Bobcanonlyhavethequeenorthejack.Hedoesn’thavethejack.So,Bobcanhavethequeen.

PorQ.P.Not(PandQ)So,not-QBobhaseitherthequeenorthejackbutnotboth.Bobhasthequeen.So,hedoesn’thavethejack.

InvalidIfP,thenQ.Q.So,P.

IfMaryisalive,thenthereisoxygen.Thereisoxygen.So,Maryisalive.

IfP,thenQ.Not-P.So,not-Q.BobishereifJoeis.Joeisn’there.So,Bobisn’t.

IfP,thenQ.So,ifQ,thenP.Iftherosesareblooming,thentheaphidsareout.So,iftheaphidsareout,thentherosesareblooming.

PorQ.Not-P.So,Q.Bobhasthequeenorthejack.Hedoesn’thavethejack.So,Bobhasthequeen.

PorQ.P.So,not-QBobhaseitherthequeenorthejack.Bobhasthequeen.So,hedoesn’thavethejack.

Whichofthebelowargumentsarevalid?

a) Ifnothingisleft,thechimpswillbecomeaggressive.Onlyshouldthechimpsbecomeaggressivewilltheyneedtobecaged.Providedthattheywillneedtobecaged,Maryshouldbepresenttosupervise.So,Maryshouldbepresenttosuperviseifnothingisleft.

b) Thatdogisbarkingagainiftheyarenotathome.Onlyifthelightsareonaretheyathome.Thelightsaren’ton.So,thatdogisbarkingagain.

c) Theratswillnoteatthepoisonedpeanutbutterprovidedthatpeanutbutterisanovelsubstanceintheirenvironment.Onlyiftheyaresatiatedwilltheratsnoteatthepoisonedpeanutbutter.Theratsaresatiated.So,thepeanutbutterisanovelsubstanceintheirenvironment.

d) Noneoftheabovearevalid.

EmotiveOverrides

• Degradationinrationalprocessing

• Alteredvaluation

• Rationalsuppressionorblock

Consider how hard it is, in normal conversation,to give voice to moral judgments without havingrecourse to the idiom of disgust or reference tothe concept of the disgusting. About persons andactions, we say … things like these: He gives methe creeps. He makes my skin crawl! Yuck! Thatmakes me what to puke. You’re revolting(repulsive, disgusting)! In a higher register wespeak of vile, odious, abhorrent, and loathsomecharacters and deeds… We perceive whatdisgusts and tend to imbue it with defectivemoral status. The Anatomy of Disgust (1997, 180)

Being so much in the gut, the idiom of disgust has certain virtues for voicingmoral assertions. It signals seriousness, commitment, indisputability,presentness, and reality. It drags the moral down from the skies towardwhich it often tends to float, wrests it from the philosophers andtheologians, and brings it back to us with a vengeance. The day-to-day nitty-gritty moral decision, moral policing, moral education, and morality talk aremore likely to involve the disgusting than the Good or the Right... that’s atleast partly because disgust … has the look of veracity about it. It is low andwithout pretense. We thus feel it trustworthy…. The Anatomy of Disgust(1997, 180-1)

WilliamIanMiller

Disgust

Somemoralemotions

DisgustFearHorrorandDreadContemptIndignation(righteousanger)Empathy

Thetargetsofemotiveresponsearenotusuallybakedin.

Theyaretoagreatdegreetheresponsetoenculturation.

Forexample,smallchildrenhavenodisgustresponse.

Moraltrainingisnotarationalprocess.But,theprocessdirectemotiveresponsestotheculturalapprovedtargets.

“moral reasoning does not cause moral judgment; rather,moral reasoning is usually a post-hoc construction, generatedafter a judgment has been reached.” “The Moral Emotions” inHandbook of Affective Sciences (2003)

JonathanHaidt

Summarizing Tetlock: “It is not surprising thatundergraduates disapprove of the administrator whomakes the wrong decision (refusing to pay); what is moreinteresting is that they also disapprove of theadministrator that makes the right decision (paying) butmulls over the dilemma… Tetlock suggests that wedisapprove of people who even consider certain morallyquestionable options; they are tainted by the act ofdeliberation.” Descartes’ Baby (2004, 128)

“We do have emotional reactions to certain situations, strong moral feelings, whatThomas Jefferson described as self-evident truths. These are not the products ofrational deliberation. We must know certain acts are wrong; we do not need reasons– and we are made uncomfortable when people try to find them.” Descartes’ Baby(2004, 129)

PaulBloom

Setup:Removedsixredballsfromcylinder.

Inference(1):Thecylindercontainsonlyredballs.Inference(2):Thecylinderlikelycontainsredballs.

Bothinferencesareequallylousy.

Observedinstancesdonotaffecttheprobabilityofunobserved.(Variantofthegambler’sfallacy.)

Gambler’sfallacy:assumingthatindependenteventsaredependent.

Thecognitiveerror:assumingthatanobservedpatternincreasestheprobabilityofitscontinuation.

SummaryofLearningSystemErrors

• Assumingthatanobservedpatternincreasestheprobabilityofitscontinuation.• Assumingthatunderlyinguniformitieswithoutreasonorcontrarytoevidencetosupportbeliefpatterncontinuation.(Thelatteristheresidualandanti-biologicalbeliefinhumannature,racenature,sexnatures,etc.)• Patternbias:assumingwithoutreasonthatanyobservedpatternmusthaveacausecannotberandom• PostHocErgoPropterHoc:assumingthatprioreventmustbethecauseoftheposteriorievent• Solutionbias:assumingpresentcasescanbesolvedinthesamewayasprioricases.

Facedwithlimitedinformationalbandwidth,thesuccessfulpoliticianwillrelyon• emotiveoverrides• irrelevancefallacies• Fallacyof‘MakingSense’

Constraintsoninformationalbandwidthsprivilegeirrationalpoliticaldiscourseoverrationalpoliticaldiscourse.

InformationalBandwidth

HijackingFallaciesofRelevance

Adhominem(PersonalAttack)torejectanargumentbyappealtopersonalirrelevantqualitiesofthepersonadvocatingtheargument.

Admisericordiam (AppealtoPity)aimstosupportsomeidea/argumentbyanappealtopity

AdPopulum (AppealtoPopularity)aimstosupportsomeidea/argumentbyanappealtothepopularityofthatidea/argument.

AdVericundiam (AppealtoAuthority)aimstosupportsomeidea/argumentbyanappealtoanauthorityfigurewhoseauthorityorexpertiseisirrelevanttothesubjectmatterathand.

Strawmanaimstosupportsomeidea/argumentbyrejectingacaricatureofanopponent’sposition.

RedHerringpresentsanapparentcriticismthatis,infact,irrelevanttotheclaim/argumentmade.

ArgumentfromTraditionaimstosupportaclaimbyappealingtothefactthattherelevantclaimhastraditionallyorpreviouslybeenaccepted.

TuQuoque (Youtoo,oranappealtohypocrisy)aimstocriticizeanopponent’spositionbynotingthattheopponent’sbehaviorhasbeeninconsistentwiththatposition.

PostHocErgoPropterHoc(FalseCause)toconcludethat,say,PisthecauseofQmerelybecausePtemporallyprecedesQ.

SlipperySlopeassumesthatsomeeventwillproduceaseriesoffurthereventswithoutanyjustificationthattheinitialeventsufficesfortheseries.

FallacyofComposition/Divisionassumesthatapropertytrueofapartis,thereby,trueofthewhole.Or,assumesthatapropertytrueofawholeis,thereby,trueofeachpart

AdIgnorantiumassumesthatsomeclaimistrue/falsebecausethereisnotevidencetothecontrary.(Themistakeisthattheabsenceofevidenceisnotevidenceofabsence.)

Adbaculum(AppealtoForce)aimstosupportsomeidea/argumentbyforce,coercion,orthreatofforce.

Fallacyof‘MakingSense’

Principle:thatsomethingmightbetrueorwouldbetruedoesnotimplythatitmay/is/mustbetrue.

‘Makessense’:

Relativetosomesetofassumptions,somethingispossibleormustbetrue.1)IfMarkwereagoat,thenhemightprefertosleepinthebarn.2)IfMarkwerethePresident,thenhewouldliveattheWhiteHouse.

Both1and2makesense.Botharereasonablytrue.

But,weareinnopositiontothinkthatImayprefertosleepinthebarnthiseveningorthatIdoliveintheWhiteHousewithoutempirical/observationalevidencethatIaminfactagoatoramthePresident.

Thefallacy:Assumingthatsomethingis trueonthebasisofthenothingmorethanitmakessensethatmightorwouldbetrue.

FallacyObservedintheWild

• Increasingcriminalpenaltiesondrugusersleadstoincreaseddeterrence

• Formerdrugusershavedistinctiveinsightandskillstohelpothersoffdrugswithoutneedforspecialtraining

• Increasedavailabilityofweaponsincreasescitizensafety

• Trickledowneconomics

• Anti-vaccineadvocatesaresimplyignorantandneedfurthereducation

• Violentvideogamesmakechildrenviolent

• Highself-esteemiskeytoacademicsuccess.

Fragilitypointsincorehumanreasoning

• Groundfloorcognitiveprocessing• Emotiveoverrides• Base-linehumanlearningsystem• Communicativebandwidthlimits

Arewedoomed?

Willpoliticaldiscoursebepermanentlyruledbytheirrationalfeaturesofourpsychology?