Thereseemtobefourconditions，thecompletefulfilmentofwhichwouldestablishasignificantproposition，apparentlyself-evident，inthehighestdegreeofcertaintyattainable:andwhichmustbeapproximatelyrealisedbythepremisesofourreasoninginanyinquiry，ifthatreasoningistoleaduscogentlytotrustworthyconclusions。
　　I。Thetermsofthepropositionmustbeclearandprecise。TherivaloriginatorsofmodernMethodology，DescartesandBacon，viewitheachotherinthestressthattheylayonthispoint；andthelatter’swarningagainstthe``notionesmaleterminatæ；’’ofordinarythoughtispeculiarlyneededinethicaldiscussion。InfactmychiefbusinessintheprecedingsurveyhasbeentofreethecommontermsofEthics，asfaraspossible，fromobjectiononthisscore。
　　II。Theself-evidenceofthepropositionmustbeascertainedbycarefulreflection。Itisneedfultoinsistonthis，becausemostpersonsareliabletoconfoundintuitions，ontheonehandwithmereimpressionsorimpulses，whichtocarefulobservationdonotpresentthemselvesasclaimingtobedictatesofReason；andontheotherhand，withmereopinions，towhichthefamiliaritythatcomesfromfrequenthearingandrepetitionoftengivesafalseappearanceofself-evidencewhichattentivereflectiondisperses。InsuchcasestheCartesianmethodoftestingtheultimatepremisesofourreasonings，byaskingourselvesifweclearlyanddistinctlyapprehendthemtobetrue，maybeofrealuse；thoughitdoesnot，asDescartessupposed，affordacompleteprotectionagainsterror。
　　Arigorousdemandforself-evidenceinourpremisesisavaluableprotectionagainstthemisleadinginfluenceofourownirrationalimpulsesonourjudgments:whileatthesametimeitnotonlydistinguishesasinadequatethemereexternalsupportofauthorityandtradition，butalsoexcludesthemoresubtleandlatenteffectoftheseinfashioningourmindstoafacileandunquestioningadmissionofcommonbutunwarrantedassumptions。
　　AndwemayobservethattheapplicationofthistestisespeciallyneededinEthics。
　　For，ontheonehand，itcannotbedeniedthatanystrongsentiment，howeverpurelysubjective，isapttotransformitselfintothesemblanceofanintuition；anditrequirescarefulcontemplationtodetecttheillusion。
　　Whateverwedesireweareapttopronouncedesirable:andwearestronglytemptedtoapproveofwhateverconductgivesuskeenpleasure。Andontheotherhand，amongtherulesofconducttowhichwecustomarilyconform，therearemanywhichreflectionshowstobereallyderivedfromsomeexternalauthority:sothateveniftheirobligationbeunquestionable，theycannotbeintuitivelyascertained。ThisisofcoursethecasewiththePositiveLawofthecommunitytowhichwebelong。Thereisnodoubtthatweought，——atleastgenerallyspeaking，——toobeythis:butwhatitiswecannotofcourseascertainbyanyprocessofabstractreflection，butonlybyconsultingReportsandStatutes。Here，however，thesourcesofknowledgearesodefiniteandconspicuous，thatweareinnodangerofconfoundingtheknowledgegainedfromstudyingthemwiththeresultsofabstractcontemplation。Thecaseissomewhatdifferentwiththetraditionalandcustomaryrulesofbehaviourwhichexistineverysociety，supplementingtheregulativeoperationofLawproper:hereitismuchmoredifficulttodistinguishtheruleswhichamoralmaniscalledupontodefineforhimself，bytheapplicationofintuitivelyknownprinciples，fromthoseastowhichsomeauthorityexternaltotheindividualisrecognisedasthefinalarbiter。
　　WemayillustratethisbyreferringtotwosystemsofruleswhichwehavebeforecomparedwithMorality；
　　theLawofHonour，andtheLawofFashionorEtiquette。Inoticedthatthereisanambiguityinthecommonterms`honourable’and`dishonourable’；
　　whicharenodoubtsometimesused，likeethicalterms，asimplyinganabsolutestandard。Still，whenwespeakoftheCodeofHonourweseemtomeanrulesofwhichtheexactnatureistobefinallydeterminedbyanappealtothegeneralopinionofwell-bredpersons:weadmitthatamanisinasense`dishonoured’whenthisopinioncondemnshim，eventhoughwemaythinkhisconductunobjectionableorevenintrinsicallyadmirable。[3]Similarly，whenweconsiderfromthepointofviewofreasontherulesofFashionorEtiquette，somemayseemusefulandcommendable，someindifferentandarbitrary，someperhapsabsurdandburdensome:butneverthelesswerecognisethatthefinalauthorityonmattersofEtiquetteisthecustomofpolitesociety；whichfeelsitselfundernoobligationofreducingitsrulestorationalprinciples。YetitmustbeobservedthateachindividualinanysocietycommonlyfindsinhimselfaknowledgenotobviouslyincompleteoftherulesofHonourandEtiquette，andanimpulsetoconformtothemwithoutrequiringanyfurtherreasonfordoingso。Eachoftenseemstoseeataglancewhatishonourableandpolitejustasclearlyasheseeswhatisright:anditrequiressomeconsiderationtodiscoverthatintheformercasescustomandopinionaregenerallythefinalauthorityfromwhichthereisnoappeal。Andeveninthecaseofrulesregardedasdistinctlymoral，wecangenerallyfindanelementthatseemstousasclearlyconventionalasthecodesjustmentioned，whenwecontemplatethemoralityofothermen，eveninourownageandcountry。Hencewemayreasonablysuspectasimilarelementinourownmoralcode:andmustadmitthegreatimportanceoftestingrigorouslyanyrulewhichwefindthatwehaveahabitualimpulsetoobey；toseewhetheritreallyexpressesorcanbereferredtoaclearintuitionofrightness。
　　III。Thepropositionsacceptedasself-evidentmustbemutuallyconsistent。Here，again，itisobviousthatanycollisionbetweentwointuitionsisaproofthatthereiserrorinoneortheother，orinboth。Still，wefrequentlyfindethicalwriterstreatingthispointverylightly。Theyappeartoregardaconflictofultimaterulesasadifficultythatmaybeignoredorputasideforfuturesolution，withoutanyslurbeingthrownonthescientificcharacteroftheconflictingformulæ；。
　　Whereassuchacollisionisabsoluteproofthatatleastoneoftheformulæ；
　　needsqualification:andsuggestsadoubtwhetherthecorrectlyqualifiedpropositionwillpresentitselfwiththesameself-evidenceasthesimplerbutinadequateone；andwhetherwehavenotmistakenforanultimateandindependentaxiomonethatisreallyderivativeandsubordinate。
　　IV。SinceitisimpliedintheverynotionofTruththatitisessentiallythesameforallminds，thedenialbyanotherofapropositionthatIhaveaffirmedhasatendencytoimpairmyconfidenceinitsvalidity。Andinfact`universal’or`general’consenthasoftenbeenheldtoconstitutebyitselfasufficientevidenceofthetruthofthemostimportantbeliefs；andispracticallytheonlyevidenceuponwhichthegreaterpartofmankindcanrely。Apropositionacceptedastrueuponthisgroundalonehas，ofcourse，neitherself-evidencenordemonstrativeevidenceforthemindthatsoacceptsit；still，thesecureacceptancethatwecommonlygivetothegeneralisationsoftheempiricalsciencesrests——eveninthecaseofexperts——largelyonthebeliefthatotherexpertshaveseenforthemselvestheevidenceforthesegeneralisations，anddonotmateriallydisagreeastoitsadequacy。Anditwillbeeasilyseenthattheabsenceofsuchdisagreementmustremainanindispensablenegativeconditionofthecertaintyofourbeliefs。ForifIfindanyofmyjudgments，intuitiveorinferential，indirectconflictwithajudgmentofsomeothermind，theremustbeerrorsomewhere:andifIhavenomorereasontosuspecterrorintheothermindthaninmyown，reflectivecomparisonbetweenthetwojudgmentsnecessarilyreducesmetemporarilytoastateofneutrality。Andthoughthetotalresultinmymindisnotexactlysuspenseofjudgment，butanalternationandconflictbetweenpositiveaffirmationbyoneactofthoughtandtheneutralitythatistheresultofanother，itisobviouslysomethingverydifferentfromscientificcertitude。
　　NowiftheaccountgivenoftheMoralityofCommonSenseintheprecedingchaptersbeinthemaincorrect，itseemsclearthat，generallyspeaking，itsmaximsdonotfulfiltheconditionsjustlaiddown。Solongastheyareleftinthestateofsomewhatvaguegeneralities，aswemeettheminordinarydiscourse，wearedisposedtoyieldthemunquestioningassent，anditmaybefairlyclaimedthattheassentisapproximatelyuniversal——inthesensethatanyexpressionofdissentiseccentricandparadoxical。
　　Butassoonasweattempttogivethemthedefinitenesswhichsciencerequires，wefindthatwecannotdothiswithoutabandoningtheuniversalityofacceptance。
　　Wefind，insomecases，thatalternativespresentthemselves，betweenwhichitisnecessarythatweshoulddecide；butbetweenwhichwecannotpretendthatCommonSensedoesdecide，andwhichoftenseemequallyornearlyequallyplausible。Inothercasesthemoralnotionseemstoresistalleffortstoobtainfromitadefiniterule:inothersitisfoundtocomprehendelementswhichwehavenomeansofreducingtoacommonstandard，exceptbytheapplicationoftheUtilitarian——orsomesimilar——method。EvenwhereweseemabletoeducefromCommonSenseamoreorlessclearreplytothequestionsraisedintheprocessofdefinition，theprinciplethatresultsisqualifiedinsocomplicatedawaythatitsself-evidencebecomesdubiousorvanishesaltogether。Andthusineachcasewhatatfirstseemedlikeanintuitionturnsouttobeeitherthemereexpressionofavagueimpulse，needingregulationandlimitationwhichitcannotitselfsupply，butwhichmustbedrawnfromsomeothersource:oracurrentopinion，thereasonablenessofwhichhasstilltobeshownbyareferencetosomeotherprinciple。
　　Inorderthatthisresultmaybeadequatelyexhibited，ImustaskthereadertotravelwithmeagainthroughtheseriesofprincipleselicitedfromCommonSenseinthepreviouschapters，andtoexaminethemfromasomewhatdifferentpointofview。Before，ourprimaryaimwastoascertainimpartiallywhatthedeliverancesofCommonSenseactuallyare:
　　wehavenowtoaskhowfartheseenunciationscanclaimtobeclassedasIntuitiveTruths。
　　Thereadershouldobservethatthroughoutthisexaminationadoubleappealismade；ontheonehandtohisindividualmoralconsciousness，and，ontheotherhand，totheCommonSenseofmankind，asexpressedgenerallybythebodyofpersonsonwhosemoraljudgmentheispreparedtorely。Iaskhim1whetherhecanstateaclear，precise，self-evidentfirstprinciple，accordingtowhichheispreparedtojudgeconductundereachhead:and2ifso，whetherthisprincipleisreallythatcommonlyappliedinpractice，bythosewhomhetakestorepresentCommonSense。
　　Ifwebeginbyconsideringthedutyofactingwisely，discussedinchap。iii。，wemayseemperhapstohavebeforeusanaxiomofundoubtedself-evidence。Foractingwiselyappearedtomeantakingtherightmeanstothebestends；i。e。takingthemeanswhichReasonindicatestotheendswhichReasonprescribes。Anditisevidentthatitmustberighttoactreasonably。Equallyundeniableistheimmediateinferencefrom，ornegativeaspectof，thisprinciple；
　　thatitiswrongtoactinoppositiontorationaljudgment。This，takeninconnexionwiththeempiricalfactofimpulsesinourmindsconflictingwithReason，gives——asanotherself-evidentprinciple——themaximofTemperanceorSelf-controlinitswidestinterpretation；i。e。`ThatreasonshouldnevergivewaytoAppetiteorPassion’。AndtheseprincipleshavesometimesbeenenouncedwithnolittlesolemnityasansweringthefundamentalquestionofEthicsandsupplyingthebasisorsummaryofadoctrineofPractice。
　　Butthisstatementofprinciplesturnsouttobeoneofthosestages，soprovokinglyfrequentinthecourseofethicalreflection，which，asfaraspracticalguidanceisconcerned，arereallybriefcircuits，leadingusbacktothepointfromwhichwestarted。
　　Orrather，topreventmisapprehension，itshouldbeobservedthatthemaximsjustgivenmaybeunderstoodintwosenses:inonesensetheyarecertainlyself-evident，buttheyarealsoinsignificant:inanothersensetheyincludemoreorlessdistinctlyadirectiontoanimportantpracticalduty，butassounderstoodtheylosetheirself-evidence。ForiftherulesofWisdomandSelf-controlmean1thatweoughtalwaystodowhatweseetobereasonable，and2thatwearenottoyieldtoanyimpulseurgingusinanoppositedirection；theysimplyaffirmthatitisourduty1generally，and2underspecialtemptations，todowhatwejudgetobeourduty:[2]
　　andconveynoinformationastothemethodandprinciplesbywhichdutyistobedetermined。
　　Butiftheserulesarefurtherunderstoodastheysometimesareunderstoodtoprescribethecultivationofahabitofactingrationally；thatis，ofreferringeachacttodefinitelyconceivedprinciplesandends，insteadofallowingittobedeterminedbyinstinctiveimpulses；
　　thenIcannotseethattheaffirmationofthisasanuniversalandabsoluteruleofdutyisself-evidentlytrue。ForwhenReasonisconsiderednotinthepresentasactuallycommanding，butasanEndofwhichafullerrealisationhastobesoughtinthefuture；thepointofviewfromwhichitssovereigntyhastobejudgedisentirelychanged。ThequestionisnolongerwhetherthedictatesofReasonoughtalwaystobeobeyed，butwhetherthedictationofReasonisalwaysaGood；whetheranydegreeofpredominanceofReasonovermereImpulsemustnecessarilytendtotheperfectionoftheconsciousselfofwhichbothareelements。Anditissurelynotself-evidentthatthispredominancecannotbecarriedtoofar；andthatReasonisnotratherself-limiting，intheknowledgethatrationalendsaresometimesbetterattainedbythosewhodonotdirectlyaimatthemasrational。CertainlyCommonSenseisinclinedtoholdthatinmanymattersinstinctisabetterspringofactionthanreason:thusitiscommonlysaidthatahealthyappetiteisabetterguidetodietthanadoctor’sprescription:and，again，thatmarriageisbetterundertakenasaconsequenceoffallinginlovethaninexecutionofatranquilanddeliberatedesign:andwebeforeobservedchap。iv。thatthereisacertainexcellenceinservicesspringingfromspontaneousaffectionwhichdoesnotattachtosimilaractsdonefrompuresenseofduty。Andinthesamewayexperienceseemstoshowthatmanyactsrequiringpromptitudeandvigourarelikelytobemoreenergeticandeffective，andthatmanyactsrequiringtactanddelicacyarelikelytobemoregracefulandpleasanttoothers，iftheyaredonenotinconsciousobediencetothedictatesofReasonbutfromothermotives。Itisnotnecessaryheretodecidehowfarthisviewistrue:itsufficestosaythatwedonotknowintuitivelythatitisnottruetosomeextent；wedonotknowthattheremaynotbe——tousePlato’sanalogy——over-governmentintheindividualsoulnolessthaninthestate。Theresiduum，then，ofclearintuitionwhichwehavesofarobtained，istheinsignificantpropositionthatitisourdutytodowhatwejudgetobeourduty。