，allpoetry，beingaspeciesofpainting，approachesusnearertotheobjectsthananyotherspeciesofnarration，throwsastrongerlightuponthem，anddelineatesmoredistinctlythoseminutecircumstanceswhich，thoughtothehistoriantheyseemsuperfluous，servemightilytoenliventheimageryandgratifythefancy。Ifitbenotnecessary，asinthe，toinformuseachtimetheherobuckleshisshoesandtieshisgarters，itwillberequisite，perhaps，toenterintoagreaterdetailthaninthe，wheretheeventsarerunoverwithsuchrapiditythatwescarcehaveleisuretobecomeacquaintedwiththesceneoraction。Wereapoet，therefore，tocomprehendinhissubjectanygreatcompassoftimeorseriesofevents，andtraceupthedeathofHectortoitsremotecausesintherapeofHelenorthejudgmentofParis，hemustdrawouthispoemtoanimmeasurablelengthinordertofillthislargecanvasswithjustpaintingandimagery。
Thereader\'simagination，inflamedwithsuchaseriesofpoeticaldescriptions，andhispassions，agitatedbyacontinualsympathywiththeactors，mustflaglongbeforetheperiodofnarrationandmustsinkintolassitudeanddisgustfromtherepeatedviolenceofthesamemovements。
，thatanepicpoetmustnottracethecausestoanygreatdistancewillfurtherappearifweconsideranotherreason，whichisdrawnfromapropertyofthepassionsstillmoreremarkableandsingular。Itisevidentthatinajustcompositionalltheaffectionsexcitedbythedifferenteventsdescribedandrepresentedaddmutualforcetoeachother；andthat，whiletheheroesareallengagedinonecommonscene，andeachactionisstronglyconnectedwiththewhole，theconcerniscontinuallyawake，andthepassionsmakeaneasytransitionfromoneobjecttoanother。
Thestrongconnectionoftheevents，asitfacilitatesthepassageofthethoughtorimaginationfromonetoanother，facilitatesalsothetransfusionofthepassionsandpreservestheaffectionstillinthesamechannelanddirection。OursympathyandconcernforEvepreparesthewayforalikesympathywithAdam:Theaffectionispreservedalmostentireinthetransition，andthemindseizesimmediatelythenewobjectasstronglyrelatedtothatwhichformerlyengageditsattention。Butwerethepoettomakeatotaldigressionfromhissubjectandintroduceanewactornowayconnectedwiththepersonages，theimagination，feelingabreachinthetransition，wouldentercoldlyintothenewscene；wouldkindlebyslowdegrees；andinreturningtothemainsubjectofthepoemwouldpass，asitwere，uponforeigngroundandhaveitsconcerntoexciteanewinordertotakepartywiththeprincipalactors。Thesameinconveniencefollowsinalesserdegreewherethepoettraceshiseventstotoogreatadistanceandbindstogetheractionswhich，thoughnotaltogetherdisjoined，havenotsostrongaconnectionasisrequisitetoforwardthetransitionofthepassions。Hencearisestheartificeofobliquenarrationemployedintheand——
wheretheheroisintroduced，atfirst，neartheperiodofhisdesigns，andafterwardsshowsus，asitwereinperspective，themoredistanteventsandcauses。Bythismeans，thereader\'scuriosityisimmediatelyexcited；theeventsfollowwithrapidity，andinaverycloseconnection；
andtheconcernpreservedalive，andcontinuallyincreasesbymeansofthenearrelationoftheobjects，fromthebeginningtotheendofthenarration。
Thesameruletakesplaceindramaticpoetry；norisiteverpermittedinaregularcompositiontointroduceanactorwhohasnoconnection，orbutasmallone，withtheprinciplepersonagesofthefable。Thespectator\'sconcernmustnotbedivertedbyanyscenesdisjoinedandseparatedfromtherest。Thisbreaksthecourseofthepassions，andpreventsthatcommunicationoftheseveralemotionsbywhichonesceneaddsforcetoanother，andtransfusesthepityandterrorwhichitexcitesuponeachsucceedingsceneuntilthewholeproducesthatrapidityofmovementwhichispeculiartothetheater。Howmustitextinguishthiswarmthoraffectiontobeentertainedonasuddenwithanewactionandnewpersonagesnowayrelatedtotheformer；tofindsosensibleabreachorvacuityinthecourseofthepassions，bymeansofthisbreachintheconnectionofideas；andinsteadofcarryingthesympathyofonesceneintothefollowing，tobeobligedeverymomenttoexciteanewconcern，andtakepartyinanewsceneofaction？
Butthoughthisruleofunityofactionbecommontodramaticandepicpoetry，wemaystillobserveadifferencebetwixtthemwhichmay，perhaps，deserveourattention。Inboththesespeciesofcompositionitisrequisitetheactionbeoneandsimple，inordertopreservetheconcernorsympathyentireandundiverted:Butinepicornarrativepoetry，thisruleisalsoestablisheduponanotherfoundation，/VIZ\\。thenecessitythatisincumbentoneverywritertoformsomeplanordesignbeforeheenteronanydiscourseornarration，andtocomprehendhissubjectinsomegeneralaspectorunitedviewwhichmaybetheconstantobjectofhisattention。Astheauthorisentirelylostindramaticcompositions，andthespectatorsupposeshimselftobereallypresentattheactionsrepresented，thisreasonhasnoplacewithregardtothestage；butanydialogueorconversationmaybeintroducedwhich，withoutimprobability，mighthavepassedinthatdeterminateportionofspacerepresentedbythetheater。Hence，inallourEnglishcomedies，eventhoseofC/ONGREVE\\，theunity
ofactionisneverstrictlyobserved；butthepoetthinksitsufficientifhispersonagesbeanywayrelatedtoeachotherbyblood，orbylivinginthesamefamily；andheafterwardsintroducestheminparticularscenes，wheretheydisplaytheirhumorsandcharacterswithoutmuchforwardingthemainaction。ThedoubleplotsofT/ERENCE\\arelicensesofthesamekind，butinalesserdegree。Andthoughthisconductbenotperfectlyregular，itisnotwhollyunsuitabletothenatureofcomedy，wherethemovementsandpassionsarenotraisedtosuchaheightasintragedy；atthesametimethatthefictionorrepresentationpalliates，incomedegree，suchlicenses。Inanarrativepoem，thefirstpropositionordesignconfinestheauthortoonesubject；andanydigressionsofthisnaturewould，atfirstview，berejectedasabsurdandmonstrous。NeitherB/OCCACE\\，L/A\\F/ONTAINE\\，noranyauthorofthatkind，thoughpleasantrybetheirchiefobject，
haveeverindulgedthem。
Toreturntothecomparisonofhistoryandepicpoetry，wemayconcludefromtheforegoingreasoningsthatasacertainunityisrequisiteinallproductions，itcannotbewantingtohistorymorethantoanyother；thatinhistorytheconnectionamongtheseveraleventswhichunitesthemintoonebodyistherelationofcauseandeffect，thesamewhichtakesplaceinepicpoetry；andthat，inthelattercomposition，thisconnectionisonlyrequiredtobecloserandmoresensibleonaccountofthelivelyimaginationandstrongpassionswhichmustbetouchedbythepoetinhisnarration。theP/ELOPONNESIAN\\warisapropersubjectforhistory，thesiegeofA/THENS\\foranepicpoem，andthedeathofA/LCIBIADES\\foratragedy。
Asthedifference，therefore，betwixthistoryandepicpoetryconsistsonlyinthedegreesofconnectionwhichbindtogetherthoseseveraleventsofwhichtheirsubjectiscomposed，itwillbedifficult，ifnotimpossible，bywordstodetermineexactlytheboundswhichseparatethemfromeachother。Thatisamatteroftastemorethanofreasoning；andperhapsthisunitymayoftenbediscoveredinasubjectwhere，atfirstview，andfromanabstractconsideration，weshouldleastexpecttofindit。
ItisevidentthatH/OMER\\，inthecourseofhisnarration，exceedsthefirstpropositionofhissubject；andthattheangerofA/CHILLES\\，whichcausedthedeathofH/ECTOR\\，isnotthesamewiththatwhichproducedsomanyillstotheG/REEKS\\。Butthestrongconnectionbetwixtthesetwomovements，thequicktransitionfromonetotheother，thecontrastbetwixttheeffectsofconcordanddiscordamongsttheprinces，andthenaturalcuriositywehavetoseeA/CHILLES\\inactionaftersolongrepose——allthesecausescarryonthereader，andproduceasufficientunityinthesubject。
ItmaybeobjectedtoM/ILTON\\thathehastraceduphiscausestotoogreatadistance，andthattherebellionoftheangelsproducesthefallofmanbyatrainofeventswhichisbothverylongandverycasual。Nottomentionthatthecreationoftheworld，whichhehasrelatedatlength，isnomorethecauseofthatcatastrophethanofthebattleofP/HARSALIA\\，oranyothereventthathaseverharpooned。
Butifweconsider，ontheotherhand，thatalltheseevents，therebellionoftheangels，thecreationoftheworld，andthefallofman，eachotherinbeingmiraculous，andoutofthecommoncourseofnature；thattheyaresupposedtobeintime；andthat，beingdetachedfromallotherevents，andbeingtheonlyoriginalfactswhichrevelationdiscovers，theystriketheeyeatonce，andnaturallyrecalleachothertothethoughtorimagination——ifweconsiderallthesecircumstances，I
say，weshallfindthatthesepartsoftheactionhaveasufficientunitytomakethembecomprehendedinonefableornarration。Towhichwemayaddthattherebellionoftheangelsandthefallofmanhaveapeculiarresemblance，asbeingcounterpartstoeachother，andpresentingtothereaderthesamemoralofobediencetoourCreator。
TheseloosehintsIhavethrowntogetherinordertoexcitethecuriosityofphilosophers，andbegetasuspicionatleastifnotafullpersuasionthatthissubjectisverycopious，andthatmanyoperationsofthehumanminddependontheconnectionorassociationofideaswhichishereexplained。Particularly，thesympathybetwixtthepassionsandimaginationwill，perhaps，appearremarkable；whileweobservethattheaffections，excitedbyoneobject，passeasilytoanotherconnectedwithit，buttransfusethemselveswithdifficulty，ornotatall，alongdifferentobjectswhichhavenomannerofconnectiontogether。Byintroducingintoanycompositionpersonagesandactionsforeign
toeachother，aninjudiciousauthorlosesthatcommunicationofemotionsbywhichalonehecaninteresttheheartandraisethepassionstotheirproperheightandperiod。thefullexplicationofthisprincipleandallitsconsequenceswouldleadusintoreasoningstooprofoundandtoocopiousfortheseEssays。Itissufficientforus，atpresent，tohaveestablishedthisconclusion，thatthethreeconnectingprinciplesofallideasaretherelationsof，，and。
SECTIONIV。
ScepticalDoubtsConcerningtheOperationsoftheUnderstanding。
PARTI。
A/LL\\theobjectsofhumanreasonorenquirymaynaturallybedividedintotwokinds，towit，，and。OfthefirstkindarethesciencesofGeometry，Algebra，andArithmetic；andinshort，everyaffirmationwhichiseitherintuitivelyordemonstrativelycertain。，isapropositionwhichexpressesarelationbetweenthesefigures。，expressesarelationbetweenthesenumbers。Propositionsofthiskindarediscoverablebythemereoperationofthought，withoutdependenceonwhatisanywhereexistentintheuniverse。
Thoughthereneverwereacircleortriangleinnature，thetruthsdemonstratedbyEuclidwouldforeverretaintheircertaintyandevidence。
Mattersoffact，whicharethesecondobjectsofhumanreason，arenotascertainedinthesamemanner；norisourevidenceoftheirtruth，howevergreat，ofalikenaturewiththeforegoing。Thecontraryofeverymatteroffactisstillpossible；becauseitcanneverimplyacontradiction，andisconceivedbythemindwiththesamefacilityanddistinctness，asifeversoconformabletoreality。isnolessintelligibleaproposition，andimpliesnomorecontradictionthantheaffirmation，。Weshouldinvain，therefore，attempttodemonstrateitsfalsehood。Wereitdemonstrativelyfalse，itwouldimplyacontradiction，andcouldneverbedistinctlyconceivedbythemind。
Itmay，therefore，beasubjectworthyofcuriosity，toenquirewhatisthenatureofthatevidence
whichassuresusofanyrealexistenceandmatteroffact，beyondthepresenttestimonyofoursenses，ortherecordsofourmemory。Thispartofphilosophy，itisobservable，hasbeenlittlecultivated，eitherbytheancientsormoderns；andthereforeourdoubtsanderrors，intheprosecutionofsoimportantanenquiry，maybethemoreexcusable；whilewemarchthroughsuchdifficultpathswithoutanyguideordirection。Theymayevenproveuseful，byexcitingcuriosity，anddestroyingthatimplicitfaithandsecurity，whichisthebaneofallreasoningandfreeenquiry。Thediscoveryofdefectsinthecommonphilosophy，ifanysuchtherebe，willnot，I
presume，beadiscouragement，butratheranincitement，asisusual，toattemptsomethingmorefullandsatisfactorythanhasyetbeenproposedtothepublic。
Allreasoningsconcerningmatteroffactseemtobefoundedontherelationof。Bymeansofthatrelationalonewecangobeyondtheevidenceofourmemoryandsenses。Ifyouweretoaskaman，whyhebelievesanymatteroffact，whichisabsent；forinstance，thathisfriendisinthecountry，orinF/RANCE\\；hewouldgiveyouareason；andthisreasonwouldbesomeotherfact；asaletterreceivedfromhim，ortheknowledgeofhisformerresolutionsandpromises。Amanfindingawatchoranyothermachineinadesertisland，wouldconcludethattherehadoncebeenmeninthatisland。Allourreasoningsconcerningfactareofthesamenature。Andhereitisconstantlysupposedthatthereisaconnexionbetweenthepresentfactandthatwhichisinferredfromit。Weretherenothingtobindthemtogether，the
inferencewouldbeentirelyprecarious。Thehearingofanarticulatevoiceandrationaldiscourseinthedarkassuresusofthepresenceofsomeperson:Why？becausethesearetheeffectsofthehumanmakeandfabric，andcloselyconnectedwithit。Ifweanatomizealltheotherreasoningsofthisnature，weshallfindthattheyarefoundedontherelationofcauseandeffect，andthatthisrelationiseithernearorremote，directorcollateral。Heatandlightarecollateraleffectsoffire，andtheoneeffectmayjustlybeinferredfromtheother。
Ifwewouldsatisfyourselves，therefore，concerningthenatureofthatevidence，whichassuresusofmattersoffact，wemustenquirehowwearriveattheknowledgeofcauseandeffect。
Ishallventuretoaffirm，asageneralproposition，whichadmitsofnoexception，thattheknowledgeofthisrelationisnot，inanyinstance，attainedbyreasonings；butarisesentirelyfromexperience，whenwefindthatanyparticularobjectsareconstantlyconjoinedwitheachother。Letanobjectbepresentedtoamanofeversostrongnaturalreasonandabilities；ifthatobjectbeentirelynewtohim，hewillnotbeable，bythemostaccurateexaminationofitssensiblequalities，todiscoveranyofitscausesoreffects。A/DAM\\，thoughhisrationalfacultiesbesupposed，attheveryfirst，entirelyperfect，couldnothaveinferredfromthefluidityandtransparencyofwaterthatitwouldsuffocatehim，orfromthelightandwarmthoffirethatitwouldconsumehim。Noobjecteverdiscovers，bythequalitieswhichappeartothesenses，eitherthecauseswhichproducedit，ortheeffectswhichwillarisefromit；norcanourreason，unassistedbyexperience，everdrawanyinferenceconcerningrealexistenceandmatteroffact。
Thisproposition，，willreadilybeadmittedwithregardtosuchobjects，asweremembertohaveoncebeenaltogetherunknowntous；sincewemustbeconsciousoftheutterinability，whichwethenlayunder，offoretellingwhatwouldarisefromthem。Presenttwosmoothpiecesofmarbletoamanwhohasnotinctureofnaturalphilosophy；hewillneverdiscoverthattheywilladheretogetherinsuchamannerastorequiregreatforcetoseparatetheminadirectline，whiletheymakesosmallaresistancetoalateralpressure。Suchevents，asbearlittleanalogytothecommoncourseofnature，arealsoreadilyconfessedtobeknownonlybyexperience；nordoesanymanimaginethattheexplosionofgunpowder，ortheattractionofaloadstone，couldeverbediscoveredbyarguments。Inlikemanner，whenaneffectissupposedtodependuponanintricatemachineryorsecretstructureofparts，wemakenodifficultyinattributingallourknowledgeofittoexperience。Whowillassertthathecangivetheultimatereason，whymilkorbreadispropernourishmentforaman，notforalionoratyger？
Butthesametruthmaynotappear，atfirstsight，tohavethesameevidencewithregardtoevents，whichhavebecomefamiliartousfromourfirstappearanceintheworld，whichbearacloseanalogytothewholecourseofnature，andwhicharesupposedtodependonthesimplequalitiesofobjects，withoutanysecretstructureofparts。
Weareapttoimaginethatwecoulddiscovertheseeffectsbythemereoperationofourreason，withoutexperience。Wefancy，thatwerewebroughtonasuddenintothisworld，wecouldatfirsthaveinferredthatoneBilliard-ballwouldcommunicatemotiontoanotheruponimpulse；andthatweneedednottohavewaitedfortheevent，inordertopronouncewithcertaintyconcerningit。Suchistheinfluenceofcustom，that，whereitisstrongest，itnotonlycoversournaturalignorance，butevenconcealsitself，andseemsnottotakeplace，merelybecauseitisfoundinthehighestdegree。
Buttoconvinceusthatallthelawsofnature，andalltheoperationsofbodieswithoutexception，areknownonlybyexperience，thefollowingreflectionsmay，perhaps，suffice。Wereanyobjectpresentedtous，andwerewerequiredtopronounceconcerningtheeffect，whichwillresultfromit，withoutconsultingpastobservation；afterwhatmanner，Ibeseechyou，mustthemindproceedinthisoperation？Itmustinventorimaginesomeevent，whichitascribestotheobjectasitseffect；anditisplainthatthisinventionmustbeentirelyarbitrary。Themindcanneverpossiblyfindtheeffectinthesupposedcause，bythemostaccuratescrutinyandexamination。Fortheeffectistotallydifferentfromthecause，andconsequentlycanneverbediscoveredinit。MotioninthesecondBilliard-ballisaquitedistincteventfrommotioninthefirst；noristhereanythingintheonetosuggestthesmallesthintoftheother。Astoneorpieceofmetalraisedintotheair，andleftwithoutanysupport，immediatelyfalls:Buttoconsiderthematter，
isthereanythingwediscoverinthissituationwhichcanbegettheideaofadownward，ratherthananupward，oranyothermotion，inthestoneormetal？
Andasthefirstimaginationorinventionofaparticulareffect，inallnaturaloperations，isarbitrary，whereweconsultnotexperience；somustwealsoesteemthesupposedtieorconnexionbetweenthecauseandeffect，whichbindsthemtogether，andrendersitimpossiblethatanyothereffectcouldresultfromtheoperationofthatcause。WhenIsee，forinstance，aBilliard-ballmovinginastraightlinetowardsanother；evensupposemotioninthesecondballshouldbyaccidentbesuggestedtome，astheresultoftheircontactorimpulse；mayInotconceive，thatahundreddifferenteventsmightaswellfollowfromthatcause？Maynotboththeseballsremainatabsoluterest？Maynotthefirstballreturninastraightline，orleapofffromthesecondinanylineordirection？Allthesesuppositionsareconsistentandconceivable。Whythenshouldwegivethepreferencetoone，whichisnomoreconsistentorconceivablethantherest？Allourreasonings
willneverbeabletoshowusanyfoundationforthispreference。
Inaword，then，everyeffectisadistincteventfromitscause。Itcouldnot，therefore，bediscoveredinthecause，andthefirstinventionorconceptionofit，，mustbeentirelyarbitrary。Andevenafteritissuggested，theconjunctionofitwiththecausemustappearequallyarbitrary；sincetherearealwaysmanyothereffects，which，toreason，mustseemfullyasconsistentandnatural。Invain，therefore，shouldwepretendtodetermineanysingleevent，orinferanycauseoreffect，withouttheassistanceofobservationandexperience。
Hencewemaydiscoverthereasonwhynophilosopher，whoisrationalandmodest，haseverpretendedtoassigntheultimatecauseofanynaturaloperation，ortoshowdistinctlytheactionofthatpower，whichproducesanysingleeffectintheuniverse。Itisconfessed，thattheutmosteffortofhumanreasonistoreducetheprinciples，productiveofnaturalphenomena，toagreatersimplicity，andtoresolvethemanyparticulareffectsintoafewgeneralcauses，bymeansofreasoningsfromanalogy，experience，andobservation。Butastothecausesofthesegeneralcauses，weshouldinvainattempttheirdiscovery；
norshallweeverbeabletosatisfyourselves，byanyparticularexplicationofthem。Theseultimatespringsandprinciplesaretotallyshutupfromhumancuriosityandenquiry。Elasticity，gravity，cohesionofparts，communicationofmotionbyimpulse；theseareprobablytheultimatecausesandprincipleswhichweshalleverdiscoverinnature；andwemayesteemourselvessufficientlyhappy，if，byaccurateenquiryandreasoning，wecantraceuptheparticularphenomenato，ornearto，thesegeneralprinciples。Themostperfectphilosophyofthenaturalkindonlystavesoffourignorancealittlelonger:Asperhapsthemostperfectphilosophyofthemoralormetaphysicalkindservesonlytodiscoverlargerportionsofit。Thustheobservationofhumanblindnessandweaknessistheresultofallphilosophy，andmeetsusateveryturn，inspiteofourendeavourstoeludeoravoidit。
Norisgeometry，whentakenintotheassistanceofnaturalphilosophy，everabletoremedythisdefect，orleadusintotheknowledgeofultimatecauses，byallthataccuracyofreasoningforwhichitissojustlycelebrated。
Everypartofmixedmathematicsproceedsuponthesuppositionthatcertainlawsareestablishedbynatureinheroperations；andabstractreasoningsareemployed，eithertoassistexperienceinthediscoveryoftheselaws，ortodeterminetheirinfluenceinparticularinstances，whereitdependsuponanyprecisedegreeofdistanceandquantity。
Thus，itisalawofmotion，discoveredbyexperience，thatthemomentorforceofanybodyinmotionisinthecompoundratioorproportionofitssolidcontentsanditsvelocity；
andconsequently，thatasmallforcemayremovethegreatestobstacleorraisethegreatestweight，if，byanycontrivanceormachinery，wecanincreasethevelocityofthatforce，soastomakeitanovermatchforitsantagonist。Geometryassistsusintheapplicationofthislaw，bygivingusthejustdimensionsofallthepartsandfigureswhichcanenterintoanyspeciesofmachine；butstillthediscoveryofthelawitselfisowingmerelytoexperience，andalltheabstractreasoningsintheworldcouldneverleadusonesteptowardstheknowledgeofit。
Whenwereason，andconsidermerelyanyobjectorcause，asitappearstothemind，independentofallobservation，itnevercouldsuggesttousthenotionofanydistinctobject，suchasitseffect；muchless，showustheinseparableandinviolableconnexionbetweenthem。Amanmustbeverysagaciouswhocoulddiscoverbyreasoningthatcrystalistheeffectofheat，andiceofcold，withoutbeingpreviouslyacquaintedwiththeoperationofthesequalities。
PARTII。
B/UT\\wehavenotyetattainedanytolerablesatisfactionwithregardtothequestionfirstproposed。
Eachsolutionstillgivesrisetoanewquestionasdifficultastheforegoing，andleadsusontofartherenquiries。Whenitisasked，theproperanswerseemstobe，thattheyarefoundedontherelationofcauseandeffect。Whenagainitisasked，itmayberepliedinoneword，E/XPERIENCE\\。Butifwestillcarryonoursiftinghumour，andask，thisimpliesanewquestion，whichmaybeofmoredifficultsolutionandexplication。Philosophers，thatgivethemselvesairsofsuperiorwisdomandsufficiency，haveahardtaskwhentheyencounterpersonsofinquisitivedispositions，whopushthemfromeverycornertowhichtheyretreat，andwhoaresureatlasttobringthemtosomedangerousdilemma。
Thebestexpedienttopreventthisconfusion，istobemodestinourpretensions；andeventodiscoverthedifficultyourselvesbeforeitisobjectedtous。Bythismeans，wemaymakeakindofmeritofourveryignorance。
Ishallcontentmyself，inthissection，withaneasytask，andshallpretendonlytogiveanegativeanswertothequestionhereproposed。Isaythen，that，evenafterwehaveexperienceoftheoperationsofcauseandeffect，ourconclusionsfromthatexperiencearenotfoundedonreasoning，oranyprocessoftheunderstanding。Thisanswerwemustendeavourbothtoexplainandtodefend。
Itmustcertainlybeallowed，thatnaturehaskeptusatagreatdistancefromallhersecrets，andhasaffordedusonlytheknowledgeofafewsuperficialqualitiesofobjects；whilesheconcealsfromusthosepowersandprinciplesonwhichtheinfluenceofthoseobjectsentirelydepends。Oursensesinformusofthecolour，weight，andconsistenceofbread；butneithersensenorreasoncaneverinformusofthosequalitieswhichfititforthenourishmentandsupportofahumanbody。Sightorfeelingconveysanideaoftheactualmotionofbodies；butastothatwonderfulforceorpower，whichwouldcarryonamovingbodyforeverinacontinuedchangeofplace，andwhichbodiesneverlosebutbycommunicatingittoothers；ofthiswecannotformthemostdistantconception。Butnotwithstandingthisignoranceofnaturalpowers[11]andprinciples，wealwayspresume，whenweseelikesensiblequalities，thattheyhavelikesecretpowers，andexpectthateffects，similartothosewhichwehaveexperienced，willfollowfromthem。Ifabodyoflikecolourandconsistencewiththatbread，whichwehaveformerlyeat，bepresentedtous，wemakenoscrupleofrepeatingtheexperiment，andforesee，
withcertainty，likenourishmentandsupport。Nowthisisaprocessofthemindorthought，ofwhichIwouldwillinglyknowthefoundation。Itisallowedonallhandsthatthereisnoknownconnexionbetweenthesensiblequalitiesandthesecretpowers；andconsequently，thatthemindisnotledtoformsuchaconclusionconcerningtheirconstantandregularconjunction，byanythingwhichitknowsoftheirnature。Astopast，itcanbeallowedtogiveandinformationofthosepreciseobjectsonly，andthatpreciseperiodoftime，whichfellunderitscognizance:Butwhythisexperienceshouldbeextendedtofuturetimes，andtootherobjects，whichforaughtweknow，maybeonlyinappearancesimilar；thisisthemainquestiononwhichIwouldinsist。Thebread，whichIformerlyeat，nourishedme；thatis，abodyofsuchsensiblequalitieswas，atthattime，enduedwithsuchsecretpowers:Butdoesitfollow，
thatotherbreadmustalsonourishmeatanothertime，andthatlikesensiblequalitiesmustalwaysbeattendedwithlikesecretpowers？Theconsequenceseemsnowisenecessary。Atleast，itmustbeacknowledgedthatthereishereaconsequencedrawnbythemind；thatthereisacertainsteptaken；aprocessofthought，andaninference，whichwantstobeexplained。Thesetwopropositionsarefarfrombeingthesame，，and。
Ishallallow，ifyouplease，thattheonepropositionmayjustlybeinferredfromtheother:Iknow，infact，thatitalwaysisinferred。Butifyouinsistthattheinferenceismadebyachainofreasoning，Idesireyoutoproducethatreasoning。Theconnexionbetweenthesepropositionsisnotintuitive。Thereisrequiredamedium，whichmayenablethemindtodrawsuchaninference，ifindeeditbedrawnbyreasoningandargument。Whatthatmediumis，Imustconfess，passesmycomprehension；anditisincumbentonthosetoproduceit，whoassertthatitreallyexists，andistheoriginofallourconclusionsconcerningmatteroffact。
Thisnegativeargumentmustcertainly，inprocessoftime，becomealtogetherconvincing，ifmanypenetratingandablephilosophersshallturntheirenquiriesthiswayandnoonebeeverabletodiscoveranyconnectingpropositionorintermediatestep，whichsupportstheunderstandinginthisconclusion。Butasthequestionisyetnew，everyreadermaynottrustsofartohisownpenetration，astoconclude，becauseanargumentescapeshisenquiry，thatthereforeitdoesnotreallyexist。Forthisreasonitmayberequisitetoventureuponamoredifficulttask；andenumeratingallthebranchesofhumanknowledge，endeavourtoshowthatnoneofthemcanaffordsuchanargument。
Allreasoningsmaybedividedintotwokinds，namely，demonstrativereasoning，orthatconcerningrelationsofideas，andmoralreasoning，orthatconcerningmatteroffactandexistence。Thattherearenodemonstrativeargumentsinthecaseseemsevident；sinceitimpliesnocontradictionthatthecourseofnaturemaychange，andthatanobject，seeminglylikethosewhichwehaveexperienced，maybeattendedwithdifferentorcontraryeffects。MayI
notclearlyanddistinctlyconceivethatabody，fallingfromtheclouds，andwhich，inallotherrespects，resemblessnow，hasyetthetasteofsaltorfeelingoffire？Isthereanymoreintelligiblepropositionthantoaffirm，thatallthetreeswillflourishinD/ECEMBER\\andJ/ANUARY\\，anddecayinM/AY\\andJ/UNE\\？Nowwhateverisintelligible，andcanbedistinctlyconceived，impliesnocontradiction，andcanneverbeprovedfalsebyanydemonstrativeargumentorabstractreasoning。
Ifwebe，therefore，engagedbyargumentstoputtrustinpastexperience，andmakeitthestandardofourfuturejudgment，theseargumentsmustbeprobableonly，orsuchasregardmatteroffactandrealexistenceaccordingtothedivisionabovementioned。Butthatthereisnoargumentofthiskind，mustappear，ifourexplicationofthatspeciesofreasoningbeadmittedassolidandsatisfactory。Wehavesaidthatallargumentsconcerningexistencearefoundedontherelationofcauseandeffect；thatourknowledgeofthatrelationisderivedentirelyfromexperience；andthatallourexperimentalconclusionsproceeduponthesuppositionthatthefuturewillbeconformabletothepast。Toendeavour，therefore，theproofofthislastsuppositionbyprobablearguments，orargumentsregardingexistence，mustbeevidentlygoinginacircle，andtakingthatforgranted，whichistheverypointinquestion。
Inreality，allargumentsfromexperiencearefoundedonthesimilaritywhichwediscoveramongnaturalobjects，andbywhichweareinducedtoexpecteffectssimilartothosewhichwehavefoundtofollowfromsuchobjects。Andthoughnonebutafoolormadmanwilleverpretendtodisputetheauthorityofexperience，ortorejectthatgreatguideofhumanlife，itmaysurelybeallowedaphilosophertohavesomuchcuriosityatleastastoexaminetheprincipleofhumannature，whichgivesthismightyauthoritytoexperience，andmakesusdrawadvantagefromthatsimilaritywhichnaturehasplacedamongdifferentobjects。
Fromcauseswhich，appear，weexpectsimilareffects。Thisisthesumofallourexperimentalconclusions。Nowitseemsevidentthat，ifthisconclusionwereformedbyreason，itwouldbeasperfectatfirst，andupononeinstance，asaftereversolongacourseofexperience。Butthecaseisfarotherwise。Nothingsolikeaseggs；yetnoone，onaccountofthisappearingsimilarity，expectsthesametasteandrelishinallofthem。Itisonlyafteralongcourseofuniformexperimentsinanykind，thatweattainafirmrelianceandsecuritywithregardtoaparticularevent。Nowwhereisthatprocessofreasoningwhich，fromoneinstance，drawsaconclusion，sodifferentfromthatwhichitinfersfromahundredinstancesthatarenowisedifferentfromthatsingleone？
ThisquestionIproposeasmuchforthesakeofinformation，aswithanintentionofraisingdifficulties。Icannotfind，Icannotimagineanysuchreasoning。ButIkeepmymindstillopentoinstruction，ifanyonewillvouchsafetobestowitonme。
Shoulditbesaidthat，fromanumberofuniformexperiments，weaconnexionbetweenthesensiblequalitiesandthesecretpowers；this，Imustconfess，seemsthesamedifficulty，couchedindifferentterms。Thequestionstillrecurs，onwhatprocessofargumentthisisfounded？Whereisthemedium，theinterposingideas，whichjoinpropositionssoverywideofeachother？
Itisconfessedthatthecolour，consistence，andothersensiblequalitiesofbreadappearnot，ofthemselves，tohaveanyconnexionwiththesecretpowersofnourishmentandsupport。Forotherwisewecouldinferthesesecretpowersfromthefirstappearanceofthesesensiblequalities，withouttheaidofexperience；contrarytothesentimentofallphilosophers，andcontrarytoplainmatteroffact。
Here，then，isournaturalstateofignorancewithregardtothepowersandinfluenceofallobjects。Howisthisremediedbyexperience？Itonlyshowsusanumberofuniformeffects，resultingfromcertainobjects，andteachesusthatthoseparticularobjects，atthatparticulartime，wereendowedwithsuchpowersandforces。Whenanewobject，endowedwithsimilarsensiblequalities，isproduced，weexpectsimilarpowersandforces，andlookforalikeeffect。Fromabodyoflikecolourandconsistencewithbreadweexpectlikenourishmentandsupport。Butthissurelyisasteporprogressofthemind，whichwantstobeexplained。Whenamansays，Andwhenhesays，；heisnotguiltyofatautology，norarethesepropositionsinanyrespectthesame。Yousaythattheonepropositionisaninferencefromtheother。Butyoumustconfessthattheinferenceisnotintuitive；neitherisitdemonstrative:Ofwhat
natureisit，then？Tosayitisexperimental，isbeggingthequestion。Forallinferencesfromexperiencesuppose，astheirfoundation，thatthefuturewillresemblethepast，andthatsimilarpowerswillbeconjoinedwithsimilarsensiblequalities。Iftherebeanysuspicionthatthecourseofnaturemaychange，andthatthepastmaybenoruleforthefuture，allexperiencebecomesuseless，andcangiverisetonoinferenceorconclusion。Itisimpossible，therefore，thatanyargumentsfromexperiencecanprovethisresemblanceofthepasttothefuture；sincealltheseargumentsarefoundedonthesuppositionofthatresemblance。Letthecourseofthingsbeallowedhithertoeversoregular；thatalone，withoutsomenewargumentorinference，provesnotthat，forthefuture，itwillcontinueso。Invaindoyoupretendtohavelearnedthenatureofbodiesfromyourpastexperience。Theirsecretnature，andconsequentlyalltheireffectsandinfluence，maychange，withoutanychangeintheirsensiblequalities。
Thishappenssometimes，andwithregardtosomeobjects:Whymayitnothappenalways，andwithregardtoallobjects？
Whatlogic，whatprocessorargumentsecuresyouagainstthissupposition？Mypractice，yousay，refutesmydoubts。
Butyoumistakethepurportofmyquestion。Asanagent，I
amquitesatisfiedinthepoint；butasaphilosopher，whohassomeshareofcuriosity，Iwillnotsayscepticism，I
wanttolearnthefoundationofthisinference。Noreading，noenquiryhasyetbeenabletoremovemydifficulty，orgivemesatisfactioninamatterofsuchimportance。CanI
dobetterthanproposethedifficultytothepublic，eventhough，perhaps，Ihavesmallhopesofobtainingasolution？
Weshallatleast，bythismeans，besensibleofourignorance，ifwedonotaugmentourknowledge。
Imustconfessthatamanisguiltyofunpardonablearrogancewhoconcludes，becauseanargumenthasescapedhisowninvestigation，thatthereforeitdoesnotreallyexist。
Imustalsoconfessthat，thoughallthelearned，forseveralages，shouldhaveemployedthemselvesinfruitlesssearchuponanysubject，itmaystill，perhaps，berashtoconcludepositivelythatthesubjectmust，therefore，passallhumancomprehension。Eventhoughweexamineallthesourcesofourknowledge，andconcludethemunfitforsuchasubject，theremaystillremainasuspicion，thattheenumerationisnotcomplete，ortheexaminationnotaccurate。Butwithregardtothepresentsubject，therearesomeconsiderationswhichseemtoremoveallthisaccusationofarroganceorsuspicionofmistake。
Itiscertainthatthemostignorantandstupidpeasants——nayinfants，nayevenbrutebeasts——improvebyexperience，andlearnthequalitiesofnaturalobjects，byobservingtheeffectswhichresultfromthem。Whenachildhasfeltthesensationofpainfromtouchingtheflameofacandle，hewillbecarefulnottoputhishandnearanycandle；
butwillexpectasimilareffectfromacausewhichissimilarinitssensiblequalitiesandappearance。Ifyouassert，therefore，thattheunderstandingofthechildisledintothisconclusionbyanyprocessofargumentorratiocination，Imayjustlyrequireyoutoproducethatargument；norhaveyouanypretencetorefusesoequitableademand。Youcannotsaythattheargumentisabstruse，andmaypossiblyescapeyourenquiry；sinceyouconfessthatitisobvioustothecapacityofamereinfant。Ifyouhesitate，therefore，amoment，orif，afterreflection，youproduceanyintricateorprofoundargument，you，inamanner，giveupthequestion，andconfessthatitisnotreasoningwhichengagesustosupposethepastresemblingthefuture，andtoexpectsimilareffectsfromcauseswhichare，toappearance，similar。ThisisthepropositionwhichI
intendedtoenforceinthepresentsection。IfIberight，I
pretendnottohavemadeanymightydiscovery。AndifIbewrong，Imustacknowledgemyselftobeindeedaverybackwardscholar；sinceIcannotnowdiscoveranargumentwhich，itseems，wasperfectlyfamiliartomelongbeforeI
wasoutofmycradle。
SECTIONV。
ScepticalSolutionoftheseDoubts。
PARTI。
T/HE\\passionforphilosophy，likethatforreligion，seemsliabletothisinconvenience，that，thoughitaimsatthecorrectionofourmanners，andextirpationofourvices，itmayonlyserve，byimprudentmanagement，tofosterapredominantinclination，andpushthemind，withmoredeterminedresolution，towardsthatsidewhichalreadytoomuch，bythebiasandpropensityofthenaturaltemper。Itiscertainthat，whileweaspiretothemagnanimousfirmnessofthephilosophicsage，andendeavourtoconfineourpleasuresaltogetherwithinourownminds，wemay，atlast，renderourphilosophylikethatofE/PICTETUS\\，andother，onlyamorerefinedsystemofselfishness，andreasonourselvesoutofallvirtueaswellassocialenjoyment。Whilewestudywithattentionthevanityofhumanlife，andturnallourthoughtstowardstheemptyandtransitorynatureofrichesandhonours，weare，perhaps，allthewhileflatteringournaturalindolence，which，hatingthebustleoftheworld，anddrudgeryofbusiness，seeksapretenceofreasontogiveitselfafullanduncontrolledindulgence。Thereis，however，onespeciesofphilosophywhichseemslittleliabletothisinconvenience，andthatbecauseitstrikesinwithnodisorderlypassionofthehumanmind，norcanmingleitselfwithanynaturalaffectionor
propensity；andthatistheA/CADEMIC\\orS/CEPTICAL\\philosophy。Theacademicsalwaystalkofdoubtandsuspenseofjudgment，ofdangerinhastydeterminations，ofconfiningtoverynarrowboundstheenquiriesoftheunderstanding，andofrenouncingallspeculationswhichlienotwithinthelimitsofcommonlifeandpractice。Nothing，therefore，canbemorecontrarythansuchaphilosophytothesupineindolenceofthemind，itsrasharrogance，itsloftypretensions，anditssuperstitiouscredulity。Everypassionismortifiedbyit，excepttheloveoftruth；andthatpassionneveris，norcanbe，carriedtotoohighadegree。Itissurprising，therefore，thatthisphilosophy，which，inalmosteveryinstance，mustbeharmlessandinnocent，shouldbethesubjectofsomuchgroundlessreproachandobloquy。But，perhaps，theverycircumstancewhichrendersitsoinnocentiswhatchieflyexposesittothepublichatredandresentment。Byflatteringnoirregularpassion，itgainsfewpartizans:Byopposingsomanyvicesandfollies，itraisestoitselfabundanceofenemies，whostigmatizeitaslibertine，profane，andirreligious。
Norneedwefearthatthisphilosophy，whileitendeavourstolimitourenquiriestocommonlife，shouldeverunderminethereasoningsofcommonlife，andcarryitsdoubtssofarastodestroyallaction，aswellasspeculation。Naturewillalwaysmaintainherrights，andprevailintheendoveranyabstractreasoningwhatsoever。
Thoughweshouldconclude，forinstance，asintheforegoingsection，that，inallreasoningsfromexperience，thereisasteptakenbythemindwhichisnotsupportedbyanyargumentorprocessoftheunderstanding；thereisnodangerthatthesereasonings，onwhichalmostallknowledgedepends，willeverbeaffectedbysuchadiscovery。Ifthemindbenotengagedbyargumenttomakethisstep，itmustbeinducedbysomeotherprincipleofequalweightandauthority；andthatprinciplewillpreserveitsinfluenceaslongashumannatureremainsthesame。Whatthatprincipleismaywellbeworththepainsofenquiry。
Supposeaperson，thoughendowedwiththestrongestfacultiesofreasonandreflection，tobebroughtonasuddenintothisworld；hewould，indeed，immediatelyobserveacontinualsuccessionofobjects，andoneeventfollowinganother；buthewouldnotbeabletodiscoveranythingfarther。Hewouldnot，atfirst，byanyreasoning，beabletoreach
theideaofcauseandeffect；sincetheparticularpowers，bywhichallnaturaloperationsareperformed，neverappeartothesenses；norisitreasonabletoconclude，merelybecauseoneevent，inoneinstance，precedesanother，thatthereforetheoneisthecause，theothertheeffect。Theirconjunctionmaybearbitraryandcasual。Theremaybenoreasontoinfertheexistenceofonefromtheappearanceoftheother。Andinaword，suchaperson，withoutmoreexperience，couldneveremployhisconjectureorreasoningconcerninganymatteroffact，orbeassuredofanythingbeyondwhatwasimmediatelypresenttohismemoryandsenses。