Love-is-a-Fallacy谬论

LoveisaFallacyWhatisafallacy?Afallacyistheuseofpoor,orinvalidreasoningfortheconstructionofanargument.Itisalsousedtorefertoanargumentwhichappearstobecorrectbutisnot.Anargumentinlogicpresentsevidenceinsupportofsomethesisorconclusion.Anargumenthastwocomponents:aconclusionandcertainpremises.Theconclusionissaidtobedrawnorinferredfromthepremises.Anargumentisdeductivelyvalidwhenitspremisesprovideevidencefortheconclusion.Anargumentthatfailstobeconclusivelydeducedisinvalid,itissaidtobefallacious.ArgumentLogicFallacies1.DictoSimpliciter（绝对判断）2.HastyGeneralization（轻率归纳）3.PostHoc（错误因果）4.ContradictoryPremises（矛盾前提）1.DictoSimpliciterPolly,Isaidgently,theargumentisafallacy.Exerciseisgoodisanunqualifiedgeneralization.Forinstance,ifyouhaveheartdisease,exerciseisbad,notgood.Manypeopleareorderedbytheirdoctorsnottoexercise.Youmustqualifythegeneralization.Youmustsayexerciseisusuallygood,orexerciseisgoodformostpeople.OtherwiseyouhavecommittedaDictoSimpliciter.Doyousee?1.DictoSimpliciter（绝对判断）DictoSimpliciterisanargumentbasedonanunqualifiedgeneralization.Theargumentappliesageneralruletoaparticularcaseinwhichsomespecialcircumstancesmaketheruleinapplicable.ExamplesWomenareonaveragenotasstrongasmenandlessabletoperformwellpolitically.Therefore,womencan'tpulltheirweightingovernmentwork.虽然女性确实在政界担任较少工作，但这不意味着女性群体中所有的人都是这样。JapanesewagedawartoChinese,whichhadnothingtodowithhumanitybuteverythingtodowithaggression.ThereforeeveryJapaneseisguiltyandshouldbecondemned.虽然日本侵华的邪恶战争任历历在目，但并不是所有的日本人都有罪，都应该受到谴责。2.HastyGeneralizationNextwetakeupafallacycalledHastyGeneralization.Listencarefully:Youcan'tspeakFrench.PeteyBurchcan'tspeakFrench.ImustthereforeconcludethatnobodyattheUniversityofMinnesotacanspeakFrench.Really?saidPolly,amazed.Nobody?Ihidmyexasperation.Polly,it'safallacy.Thegeneralizationisreachedtoohastily.Therearetoofewinstancetosupportsuchaconclusion.2.HastyGeneralization（轻率归纳）Hastygeneralizationisafallacyinwhichaconclusionisnotlogicallyjustifiedbysufficientorunbiasedevidence.Ahastygeneralizationalwaysproceedsfromtheparticulartothegeneral.HastyGeneralizationItspattern:XistrueforA.XistrueforB.XistrueforC.XistrueforD.Therefore,XistrueforE,F,G,etc.ExampleMikefailedbiologyexam.Janefailedbiologyexam.Mariafailedbiologyexam.Therefore,Iconcludethatmoststudentswhotakebiologyexamwillfailit.AnalysisInunderstandingandcharacterizinggeneralsituations,alogiciancannotnormallyexamineeverysingleexample.However,theexamplesusedininductivereasoningshouldbetypicaloftheproblemorsituationathand.MaybeMike,Jane,andMariaareexceptionallypoorstudents.Maybetheyweresickandmissedtoomanylectures.Ifalogicianwantstomakethecasethatmoststudentswillfailbiologyexam,sheshould(a)getaverylargesample--atleastonelargerthanthreeor(b)ifthatisn'tpossible,shewillneedtogooutofhiswaytoprovetothereaderthatherthreesamplesaresomehowrepresentativeofthenorm.3.PostHocListentothis:Let'snottakeBillonourpicnic.Everytimewetakeitoutwithus,itrains.Iknowsomebodyjustlikethat,sheexclaimed.Agirlbackhome-EulaBecker,hernameis.Itneverfails.Everysingletimewetakeheronapicnic...Polly,Isaidsharply,it'safallacy.EulaBeckerdoesn'tcausetherain.Shehasnoconnectionwiththerain.YouareguiltyofPostHocifyoublameEulaBecker.3.PostHoc（错误因果）PostHocisafallacyinwhichoneeventissaidtobethecauseofalatereventsimplybecauseitoccurredearlier.PostHocisafallacywiththefollowingform:1.AoccursbeforeB.2.ThereforeAisthecauseofB.ExamplesJoanisscratchedbyacatwhilevisitingherfriend.Twodayslatershecomesdownwithafever.Joanconcludesthatthecat'sscratchmustbethecauseofherillness.Mostyoungcriminalswatchviolentmoviesbeforetheycommittheircrimes;obviously,violentmoviesleadtojuveniledelinquency.甲事情发生在乙事情之前，这并不代表着先发生的甲事情就是后发生的乙事情的原因。4.ContradictoryPremisesIfGodcandoanything,canHemakeastonesoheavythatHewon'tbeabletoliftit?Ofcourse,sherepliedpromptly.ButifHecandoanything,Hecanliftthestone,Ipointedout.Yeah,shesaidthoughtfully.Well,thenIguessHecan'tmakethestone.ButHecandoanything,Iremindedher.Shescratchedherpretty,emptyhead.I'mallconfused,sheadmitted.Ofcourseyouare.Becausewhenthepremisesofanargumentcontradicteachother,therecanbenoargument.Ifthereisanirresistibleforce,therecanbenoimmovableobject.Ifthereisanimmovableobject,therecanbenoirresistibleforce.Getit?4.ContradictoryPremises（矛盾前提）ContradictoryPremisesisanargumentthatdrawsaconclusionfrominconsistentorincompatiblepremises.Essentially,apropositioniscontradictorywhenitassertsanddeniesthesamething.Sometimesitisdifficulttodistinguishbetweenrealandapparentincompatiblepremises.Let'slookattheexamplebelow.Afathersaidtohisson:youcantrustnoone.AnalysisThefatherwhoistryingtoconvincehischildthatnooneshouldbetrustedisobviouslymakinganexceptionofhimself.Ifhereallyweremakingincompatibleclaims('sinceyoushouldtrustnoone,andyoushouldtrustme'),norationalconclusioncouldorshouldbedrawnbythechild.However,theincompatiblepremisesareonlyapparent;thefatherhascarelesslyoverstatedthefirstpremise.Ifhehadsaid,Don'ttrustmostpeopleorTrustveryfewpeople,orDon'ttrustanyoneexceptme,hewouldhav