I
THETHREEHYPOTHESESRESPECTINGTHEHISTORYOFNATURE
Weliveinandformpartofasystemofthingsofimmensediversityandperplexity，whichwecallNature；anditisamatterofthedeepestinteresttoallofusthatweshouldformjustconceptionsoftheconstitutionofthatsystemandofitspasthistory。Withrelationtothisuniverse，manis，inextent，littlemorethanamathematicalpoint；indurationbutafleetingshadow；heisamerereedshakeninthewindsofforce。
ButasPascallongagoremarked，althoughamerereed，heisathinkingreed；andinvirtueofthatwonderfulcapacityofthought，hehasthepowerofframingforhimselfasymbolicconceptionoftheuniverse，which，althoughdoubtlesshighlyimperfectandinadequateasapictureofthegreatwhole，isyetsufficienttoservehimasachartfortheguidanceofhispracticalaffairs。IthastakenlongagesoftoilsomeandoftenfruitlesslabourtoenablemantolooksteadilyattheshiftingscenesofthephantasmagoriaofNature，tonoticewhatisfixedamongherfluctuations，andwhatisregularamongherapparentirregularities；anditisonlycomparativelylately，withinthelastfewcenturies，thattheconceptionofauniversalorderandofadefinitecourseofthings，whichwetermthecourseofNature，hasemerged。
But，onceoriginated，theconceptionoftheconstancyoftheorderofNaturehasbecomethedominantideaofmodernthought。
Toanypersonwhoisfamiliarwiththefactsuponwhichthatconceptionisbased，andiscompetenttoestimatetheirsignificance，ithasceasedtobeconceivablethatchanceshouldhaveanyplaceintheuniverse，orthateventsshoulddependuponanybutthenaturalsequenceofcauseandeffect。Wehavecometolookuponthepresentasthechildofthepastandastheparentofthefuture；and，aswehaveexcludedchancefromaplaceintheuniverse，soweignore，evenasapossibility，thenotionofanyinterferencewiththeorderofNature。
Whatevermaybemen’sspeculativedoctrines，itisquitecertainthateveryintelligentpersonguideshislifeandriskshisfortuneuponthebeliefthattheorderofNatureisconstant，andthatthechainofnaturalcausationisneverbroken。
Infact，nobeliefwhichweentertainhassocompletealogicalbasisasthattowhichIhavejustreferred。Ittacitlyunderlieseveryprocessofreasoning；itisthefoundationofeveryactofthewill。Itisbaseduponthebroadestinduction，anditisverifiedbythemostconstant，regular，anduniversalofdeductiveprocesses。Butwemustrecollectthatanyhumanbelief，howeverbroaditsbasis，howeverdefensibleitmayseem，is，afterall，onlyaprobablebelief，andthatourwidestandsafestgeneralisationsaresimplystatementsofthehighestdegreeofprobability。ThoughwearequiteclearabouttheconstancyoftheorderofNature，atthepresenttime，andinthepresentstateofthings，itbynomeansnecessarilyfollowsthatwearejustifiedinexpandingthisgeneralisationintotheinfinitepast，andindenying，absolutely，thattheremayhavebeenatimewhenNaturedidnotfollowafixedorder，whentherelationsofcauseandeffectwerenotdefinite，andwhenextra-
naturalagenciesinterferedwiththegeneralcourseofNature。
Cautiousmenwillallowthatauniversesodifferentfromthatwhichweknowmayhaveexisted；justasaverycandidthinkermayadmitthataworldinwhichtwoandtwodonotmakefour，andinwhichtwostraightlinesdoincloseaspace，mayexist。
Butthesamecautionwhichforcestheadmissionofsuchpossibilitiesdemandsagreatdealofevidencebeforeitrecognisesthemtobeanythingmoresubstantial。Andwhenitisassertedthat，somanythousandyearsago，eventsoccurredinamannerutterlyforeigntoandinconsistentwiththeexistinglawsofNature，men，whowithoutbeingparticularlycautious，aresimplyhonestthinkers，unwillingtodeceivethemselvesordeludeothers，askfortrustworthyevidenceofthefact。
Didthingssohappenordidtheynot？Thisisahistoricalquestion，andonetheanswertowhichmustbesoughtinthesamewayasthesolutionofanyotherhistoricalproblem。
SofarasIknow，thereareonlythreehypotheseswhicheverhavebeenentertained，orwhichwellcanbeentertained，respectingthepasthistoryofNature。Iwill，inthefirstplace，statethehypotheses，andthenIwillconsiderwhatevidencebearinguponthemisinourpossession，andbywhatlightofcriticismthatevidenceistobeinterpreted。
Uponthefirsthypothesis，theassumptionis，thatphenomenaofNaturesimilartothoseexhibitedbythepresentworldhavealwaysexisted；inotherwords，thattheuniversehasexisted，fromalleternity，inwhatmaybebroadlytermeditspresentcondition。
Thesecondhypothesisisthatthepresentstateofthingshashadonlyalimitedduration；andthat，atsomeperiodinthepast，aconditionoftheworld，essentiallysimilartothatwhichwenowknow，cameintoexistence，withoutanyprecedentconditionfromwhichitcouldhavenaturallyproceeded。
TheassumptionthatsuccessivestatesofNaturehavearisen，eachwithoutanyrelationofnaturalcausationtoanantecedentstate，isameremodificationofthissecondhypothesis。
Thethirdhypothesisalsoassumesthatthepresentstateofthingshashadbutalimitedduration；butitsupposesthatthisstatehasbeenevolvedbyanaturalprocessfromanantecedentstate，andthatfromanother，andsoon；and，onthishypothesis，theattempttoassignanylimittotheseriesofpastchangesis，usually，givenup。
ItissoneedfultoformclearanddistinctnotionsofwhatisreallymeantbyeachofthesehypothesesthatIwillaskyoutoimaginewhat，accordingtoeach，wouldhavebeenvisibletoaspectatoroftheeventswhichconstitutethehistoryoftheearth。Onthefirsthypothesis，howeverfarbackintimethatspectatormightbeplaced，hewouldseeaworldessentially，thoughperhapsnotinallitsdetails，similartothatwhichnowexists。Theanimalswhichexistedwouldbetheancestorsofthosewhichnowlive，andsimilartothem；theplants，inlikemanner，wouldbesuchasweknow；andthemountains，plains，andwaterswouldforeshadowthesalientfeaturesofourpresentlandandwater。Thisviewwasheldmoreorlessdistinctly，sometimescombinedwiththenotionofrecurrentcyclesofchange，inancienttimes；anditsinfluencehasbeenfeltdowntothepresentday。ItisworthyofremarkthatitisahypothesiswhichisnotinconsistentwiththedoctrineofUniformitarianism，withwhichgeologistsarefamiliar。
ThatdoctrinewasheldbyHutton，andinhisearlierdaysbyLyell。Huttonwasstruckbythedemonstrationofastronomersthattheperturbationsoftheplanetarybodies，howevergreattheymaybe，yetsoonerorlaterrightthemselves；andthatthesolarsystempossessesaself-adjustingpowerbywhichtheseaberrationsareallbroughtbacktoameancondition。
Huttonimaginedthatthelikemightbetrueofterrestrialchanges；althoughnoonerecognisedmoreclearlythanhethefactthatthedrylandisbeingconstantlywasheddownbyrainandriversanddepositedinthesea；andthatthus，inalongerorshortertime，theinequalitiesoftheearth’ssurfacemustbelevelled，anditshighlandsbroughtdowntotheocean。
But，takingintoaccounttheinternalforcesoftheearth，which，upheavingthesea-bottomgiverisetonewland，hethoughtthattheseoperationsofdegradationandelevationmightcompensateeachother；andthatthus，foranyassignabletime，thegeneralfeaturesofourplanetmightremainwhattheyare。
Andinasmuchas，underthesecircumstances，thereneedbenolimittothepropagationofanimalsandplants，itisclearthattheconsistentworkingoutoftheuniformitarianideamightleadtotheconceptionoftheeternityoftheworld。NotthatImeantosaythateitherHuttonorLyellheldthisconception——
assuredlynot；theywouldhavebeenthefirsttorepudiateit。
Nevertheless，thelogicaldevelopmentofsomeoftheirargumentstendsdirectlytowardsthishypothesis。
Thesecondhypothesissupposesthatthepresentorderofthings，atsomenoveryremotetime，hadasuddenorigin，andthattheworld，suchasitnowis，hadchaosforitsphenomenalantecedent。ThatisthedoctrinewhichyouwillfindstatedmostfullyandclearlyintheimmortalpoemofJohnMilton——theEnglishDivinaCommedia——\"ParadiseLost。\"Ibelieveitislargelytotheinfluenceofthatremarkablework，combinedwiththedailyteachingstowhichwehavealllistenedinourchildhood，thatthishypothesisowesitsgeneralwidediffusionasoneofthecurrentbeliefsofEnglish-speakingpeople。Ifyouturntotheseventhbookof\"ParadiseLost，\"youwillfindtherestatedthehypothesistowhichIrefer，whichisbrieflythis：
Thatthisvisibleuniverseofourscameintoexistenceatnogreatdistanceoftimefromthepresent；andthatthepartsofwhichitiscomposedmadetheirappearance，inacertaindefiniteorder，inthespaceofsixnaturaldays，insuchamannerthat，onthefirstofthesedays，lightappeared；that，onthesecond，thefirmament，orsky，separatedthewatersabove，fromthewatersbeneaththefirmament；that，onthethirdday，thewatersdrewawayfromthedryland，anduponitavariedvegetablelife，similartothatwhichnowexists，madeitsappearance；thatthefourthdaywassignalisedbytheapparitionofthesun，thestars，themoon，andtheplanets；
that，onthefifthday，aquaticanimalsoriginatedwithinthewaters；that，onthesixthday，theearthgaverisetoourfour-
footedterrestrialcreatures，andtoallvarietiesofterrestrialanimalsexceptbirds，whichhadappearedontheprecedingday；and，finally，thatmanappearedupontheearth，andtheemergenceoftheuniversefromchaoswasfinished。
Miltontellsus，withouttheleastambiguity，whataspectatorofthesemarvellousoccurrenceswouldhavewitnessed。Idoubtnotthathispoemisfamiliartoallofyou，butIshouldliketorecallonepassagetoyourminds，inorderthatImaybejustifiedinwhatIhavesaidregardingtheperfectlyconcrete，definite，pictureoftheoriginoftheanimalworldwhichMiltondraws。Hesays：——
\"Thesixth，andofcreationlast，aroseWitheveningharpandmatin，whenGodsaid，’Lettheearthbringforthsoullivinginherkind，Cattleandcreepingthings，andbeastoftheearth。
Eachintheirkind！’Theearthobeyed，and，straightOpeningherfertilewomb，teemedatabirthInnumerouslivingcreatures，perfectforms，Limbedandfull-grown。Outofthegrounduprose，Asfromhislair，thewildbeast，wherehewonsInforestwild，inthicket，brake，orden；
Amongthetreesinpairstheyrose，theywalked；
Thecattleinthefieldsandmeadowsgreen；
Thoserareandsolitary；theseinflocksPasturingatonce，andinbroadherdsupsprung。
Thegrassyclodsnowcalved；nowhalfappearsThetawnylion，pawingtogetfreeHishinderparts——thensprings，asbrokefrombonds，Andrampantshakeshisbrindedmane；theounce，Thelibbard，andthetiger，asthemoleRising，thecrumbledearthabovethemthrewInhillocks；theswiftstagfromundergroundBoreuphisbranchinghead；scarcefromhismouldBehemoth，biggestbornofearth，upheavedHisvastness；fleecedtheflocksandbleatingroseAsplants；ambiguousbetweenseaandland，Theriver-horseandscalycrocodile。
Atoncecameforthwhatevercreepstheground，Insectorworm。\"
Thereisnodoubtastothemeaningofthisstatement，norastowhatamanofMilton’sgeniusexpectedwouldhavebeenactuallyvisibletoaneye-witnessofthismodeoforiginationoflivingthings。
Thethirdhypothesis，orthehypothesisofevolution，supposesthat，atanycomparativelylateperiodofpasttime，ourimaginaryspectatorwouldmeetwithastateofthingsverysimilartothatwhichnowobtains；butthatthelikenessofthepasttothepresentwouldgraduallybecomelessandless，inproportiontotheremotenessofhisperiodofobservationfromthepresentday；thattheexistingdistributionofmountainsandplains，ofriversandseas，wouldshowitselftobetheproductofaslowprocessofnaturalchangeoperatinguponmoreandmorewidelydifferentantecedentconditionsofthemineralframe-workoftheearth；until，atlength，inplaceofthatframe-work，hewouldbeholdonlyavastnebulousmass，representingtheconstituentsofthesunandoftheplanetarybodies。Precedingtheformsoflifewhichnowexist，ourobserverwouldseeanimalsandplants，notidenticalwiththem，butlikethem，increasingtheirdifferenceswiththeirantiquityand，atthesametime，becomingsimplerandsimpler；until，finally，theworldoflifewouldpresentnothingbutthatundifferentiatedprotoplasmicmatterwhich，sofarasourpresentknowledgegoes，isthecommonfoundationofallvitalactivity。
Thehypothesisofevolutionsupposesthatinallthisvastprogressiontherewouldbenobreachofcontinuity，nopointatwhichwecouldsay\"Thisisanaturalprocess，\"and\"Thisisnotanaturalprocess；\"butthatthewholemightbecomparedtothatwonderfuloperationofdevelopmentwhichmaybeseengoingoneverydayunderoureyes，invirtueofwhichtherearises，outofthesemi-fluidcomparativelyhomogeneoussubstancewhichwecallanegg，thecomplicatedorganisationofoneofthehigheranimals。That，inafewwords，iswhatismeantbythehypothesisofevolution。
Ihavealreadysuggestedthat，indealingwiththesethreehypotheses，inendeavouringtoformajudgmentastowhichofthemisthemoreworthyofbelief，orwhethernoneisworthyofbelief——inwhichcaseourconditionofmindshouldbethatsuspensionofjudgmentwhichissodifficulttoallbuttrainedintellects——weshouldbeindifferenttoallapriori
considerations。Thequestionisaquestionofhistoricalfact。
Theuniversehascomeintoexistencesomehoworother，andtheproblemis，whetheritcameintoexistenceinonefashion，orwhetheritcameintoexistenceinanother；and，asanessentialpreliminarytofurtherdiscussion，permitmetosaytwoorthreewordsastothenatureandthekindsofhistoricalevidence。
Theevidenceastotheoccurrenceofanyeventinpasttimemayberangedundertwoheadswhich，forconvenience’sake，Iwillspeakofastestimonialevidenceandascircumstantialevidence。
BytestimonialevidenceImeanhumantestimony；andbycircumstantialevidenceImeanevidencewhichisnothumantestimony。LetmeillustratebyafamiliarexamplewhatI
understandbythesetwokindsofevidence，andwhatistobesaidrespectingtheirvalue。
Supposethatamantellsyouthathesawapersonstrikeanotherandkillhim；thatistestimonialevidenceofthefactofmurder。Butitispossibletohavecircumstantialevidenceofthefactofmurder；thatistosay，youmayfindamandyingwithawounduponhisheadhavingexactlytheformandcharacterofthewoundwhichismadebyanaxe，and，withduecareintakingsurroundingcircumstancesintoaccount，youmayconcludewiththeutmostcertaintythatthemanhasbeenmurdered；
thathisdeathistheconsequenceofablowinflictedbyanothermanwiththatimplement。Weareverymuchinthehabitofconsideringcircumstantialevidenceasoflessvaluethantestimonialevidence，anditmaybethat，wherethecircumstancesarenotperfectlyclearandintelligible，itisadangerousandunsafekindofevidence；butitmustnotbeforgottenthat，inmanycases，circumstantialisquiteasconclusiveastestimonialevidence，andthat，notunfrequently，itisagreatdealweightierthantestimonialevidence。
Forexample，takethecasetowhichIreferredjustnow。
Thecircumstantialevidencemaybebetterandmoreconvincingthanthetestimonialevidence；foritmaybeimpossible，undertheconditionsthatIhavedefined，tosupposethatthemanmethisdeathfromanycausebuttheviolentblowofanaxewieldedbyanotherman。Thecircumstantialevidenceinfavourofamurderhavingbeencommitted，inthatcase，isascompleteandasconvincingasevidencecanbe。Itisevidencewhichisopentonodoubtandtonofalsification。Butthetestimonyofawitnessisopentomultitudinousdoubts。Hemayhavebeenmistaken。Hemayhavebeenactuatedbymalice。Ithasconstantlyhappenedthatevenanaccuratemanhasdeclaredthatathinghashappenedinthis，that，ortheotherway，whenacarefulanalysisofthecircumstantialevidencehasshownthatitdidnothappeninthatway，butinsomeotherway。
Wemaynowconsidertheevidenceinfavouroforagainstthethreehypotheses。Letmefirstdirectyourattentiontowhatistobesaidaboutthehypothesisoftheeternityofthestateofthingsinwhichwenowlive。Whatwillfirststrikeyouis，thatitisahypothesiswhich，whethertrueorfalse，isnotcapableofverificationbyanyevidence。For，inordertoobtaineithercircumstantialortestimonialevidencesufficienttoprovetheeternityofdurationofthepresentstateofnature，youmusthaveaneternityofwitnessesoraninfinityofcircumstances，andneitheroftheseisattainable。Itisutterlyimpossiblethatsuchevidenceshouldbecarriedbeyondacertainpointoftime；andallthatcouldbesaid，atmost，wouldbe，thatsofarastheevidencecouldbetraced，therewasnothingtocontradictthehypothesis。Butwhenyoulook，nottothetestimonialevidence——which，consideringtherelativeinsignificanceoftheantiquityofhumanrecords，mightnotbegoodformuchinthiscase——buttothecircumstantialevidence，thenyoufindthatthishypothesisisabsolutelyincompatiblewithsuchevidenceaswehave；whichisofsoplainandsosimpleacharacterthatitisimpossibleinanywaytoescapefromtheconclusionswhichitforcesuponus。
Youare，doubtless，allawarethattheoutersubstanceoftheearth，whichaloneisaccessibletodirectobservation，isnotofahomogeneouscharacter，butthatitismadeupofanumberoflayersorstrata，thetitlesoftheprincipalgroupsofwhichareplacedupontheaccompanyingdiagram。Eachofthesegroupsrepresentsanumberofbedsofsand，ofstone，ofclay，ofslate，andofvariousothermaterials。
Oncarefulexamination，itisfoundthatthematerialsofwhicheachoftheselayersofmoreorlesshardrockarecomposedare，forthemostpart，ofthesamenatureasthosewhichareatpresentbeingformedunderknownconditionsonthesurfaceoftheearth。Forexample，thechalk，whichconstitutesagreatpartoftheCretaceousformationinsomepartsoftheworld，ispracticallyidenticalinitsphysicalandchemicalcharacterswithasubstancewhichisnowbeingformedatthebottomoftheAtlanticOcean，andcoversanenormousarea；otherbedsofrockarecomparablewiththesandswhicharebeingformeduponsea-
shores，packedtogether，andsoon。Thus，omittingrocksofigneousorigin，itisdemonstrablethatallthesebedsofstone，ofwhichatotalofnotlessthanseventythousandfeetisknown，havebeenformedbynaturalagencies，eitheroutofthewasteandwashingofthedryland，orelsebytheaccumulationoftheexuviaeofplantsandanimals。Manyofthesestrataarefullofsuchexuviae——theso-called\"fossils。\"Remainsofthousandsofspeciesofanimalsandplants，asperfectlyrecognisableasthoseofexistingformsoflifewhichyoumeetwithinmuseums，orastheshellswhichyoupickupuponthesea-beach，havebeenimbeddedintheancientsands，ormuds，orlimestones，justastheyarebeingimbeddednow，insandy，orclayey，orcalcareoussubaqueousdeposits。Theyfurnishuswitharecord，thegeneralnatureofwhichcannotbemisinterpreted，ofthekindsofthingsthathaveliveduponthesurfaceoftheearthduringthetimethatisregisteredbythisgreatthicknessofstratifiedrocks。Butevenasuperficialstudyofthesefossilsshowsusthattheanimalsandplantswhichliveatthepresenttimehavehadonlyatemporaryduration；fortheremainsofsuchmodernformsoflifearemetwith，forthemostpart，onlyintheuppermostorlatesttertiaries，andtheirnumberrapidlydiminishesinthelowerdepositsofthatepoch。Intheoldertertiaries，theplacesofexistinganimalsandplantsaretakenbyotherforms，asnumerousanddiversifiedasthosewhichlivenowinthesamelocalities，butmoreorlessdifferentfromthem；inthemesozoicrocks，thesearereplacedbyothersyetmoredivergentfrommoderntypes；and，inthepaleozoicformations，thecontrastisstillmoremarked。Thusthecircumstantialevidenceabsolutelynegativestheconceptionoftheeternityofthepresentconditionofthings。Wecansay，withcertainty，thatthepresentconditionofthingshasexistedforacomparativelyshortperiod；andthat，sofarasanimalandvegetablenatureareconcerned，ithasbeenprecededbyadifferentcondition。Wecanpursuethisevidenceuntilwereachthelowestofthestratifiedrocks，inwhichwelosetheindicationsoflifealtogether。Thehypothesisoftheeternityofthepresentstateofnaturemaythereforebeputoutofcourt。
Fig。1。——IdealSectionoftheCrustoftheEarth。
WenowcometowhatIwilltermMilton’shypothesis——thehypothesisthatthepresentconditionofthingshasenduredforacomparativelyshorttime；and，atthecommencementofthattime，cameintoexistencewithinthecourseofsixdays。IdoubtnotthatitmayhaveexcitedsomesurpriseinyourmindsthatI
shouldhavespokenofthisasMilton’shypothesis，ratherthanthatIshouldhavechosenthetermswhicharemorecustomary，suchas\"thedoctrineofcreation，\"or\"theBiblicaldoctrine，\"
or\"thedoctrineofMoses，\"allofwhichdenominations，asappliedtothehypothesistowhichIhavejustreferred，arecertainlymuchmorefamiliartoyouthanthetitleoftheMiltonichypothesis。ButIhavehadwhatIcannotbutthinkareveryweightyreasonsfortakingthecoursewhichIhavepursued。
Inthefirstplace，Ihavediscardedthetitleofthe\"doctrineofcreation，\"becausemypresentbusinessisnotwiththequestionwhytheobjectswhichconstituteNaturecameintoexistence，butwhentheycameintoexistence，andinwhatorder。
ThisisasstrictlyahistoricalquestionasthequestionwhentheAnglesandtheJutesinvadedEngland，andwhethertheyprecededorfollowedtheRomans。Butthequestionaboutcreationisaphilosophicalproblem，andonewhichcannotbesolved，orevenapproached，bythehistoricalmethod。Whatwewanttolearnis，whetherthefacts，sofarastheyareknown，affordevidencethatthingsaroseinthewaydescribedbyMilton，orwhethertheydonot；and，whenthatquestionissettleditwillbetimeenoughtoinquireintothecausesoftheirorigination。
Inthesecondplace，IhavenotspokenofthisdoctrineastheBiblicaldoctrine。ItisquitetruethatpersonsasdiverseintheirgeneralviewsasMiltontheProtestantandthecelebratedJesuitFatherSuarez，eachputuponthefirstchapterofGenesistheinterpretationembodiedinMilton’spoem。Itisquitetruethatthisinterpretationisthatwhichhasbeeninstilledintoeveryoneofusinourchildhood；butIdonotforonemomentventuretosaythatitcanproperlybecalledtheBiblicaldoctrine。Itisnotmybusiness，anddoesnotliewithinmycompetency，tosaywhattheHebrewtextdoes，andwhatitdoesnotsignify；moreover，wereItoaffirmthatthisistheBiblicaldoctrine，Ishouldbemetbytheauthorityofmanyeminentscholars，tosaynothingofmenofscience，who，atvarioustimes，haveabsolutelydeniedthatanysuchdoctrineistobefoundinGenesis。Ifwearetolistentomanyexpositorsofnomeanauthority，wemustbelievethatwhatseemssoclearlydefinedinGenesis——asifverygreatpainshadbeentakenthatthereshouldbenopossibilityofmistake——isnotthemeaningofthetextatall。Theaccountisdividedintoperiodsthatwemaymakejustaslongorasshortasconveniencerequires。Wearealsotounderstandthatitisconsistentwiththeoriginaltexttobelievethatthemostcomplexplantsandanimalsmayhavebeenevolvedbynaturalprocesses，lastingformillionsofyears，outofstructurelessrudiments。ApersonwhoisnotaHebrewscholarcanonlystandasideandadmirethemarvellousflexibilityofalanguagewhichadmitsofsuchdiverseinterpretations。Butassuredly，inthefaceofsuchcontradictionsofauthorityuponmattersrespectingwhichheisincompetenttoformanyjudgment，hewillabstain，asIdo，fromgivinganyopinion。
Inthethirdplace，IhavecarefullyabstainedfromspeakingofthisastheMosaicdoctrine，becausewearenowassuredupontheauthorityofthehighestcriticsandevenofdignitariesoftheChurch，thatthereisnoevidencethatMoseswrotetheBookofGenesis，orknewanythingaboutit。YouwillunderstandthatI
givenojudgment——itwouldbeanimpertinenceuponmyparttovolunteerevenasuggestion——uponsuchasubject。But，thatbeingthestateofopinionamongthescholarsandtheclergy，itiswellfortheunlearnedinHebrewlore，andforthelaity，toavoidentanglingthemselvesinsuchavexedquestion。
Happily，Miltonleavesusnoexcusefordoubtingwhathemeans，andIshallthereforebesafeinspeakingoftheopinioninquestionastheMiltonichypothesis。
Nowwehavetotestthathypothesis。Formypart，Ihavenoprejudiceonewayortheother。Ifthereisevidenceinfavourofthisview，Iamburdenedbynotheoreticaldifficultiesinthewayofacceptingit；buttheremustbeevidence。
Scientificmengetanawkwardhabit——no，Iwon’tcallitthat，foritisavaluablehabit——ofbelievingnothingunlessthereisevidenceforit；andtheyhaveawayoflookinguponbeliefwhichisnotbaseduponevidence，notonlyasillogical，butasimmoral。Wewill，ifyouplease，testthisviewbythecircumstantialevidencealone；for，fromwhatIhavesaid，youwillunderstandthatIdonotproposetodiscussthequestionofwhattestimonialevidenceistobeadducedinfavourofit。
Ifthosewhosebusinessitistojudgearenotatoneastotheauthenticityoftheonlyevidenceofthatkindwhichisoffered，norastothefactstowhichitbearswitness，thediscussionofsuchevidenceissuperfluous。
ButImaybepermittedtoregretthisnecessityofrejectingthetestimonialevidencetheless，becausetheexaminationofthecircumstantialevidenceleadstotheconclusion，notonlythatitisincompetenttojustifythehypothesis，butthat，sofarasitgoes，itiscontrarytothehypothesis。
TheconsiderationsuponwhichIbasethisconclusionareofthesimplestpossiblecharacter。TheMiltonichypothesiscontainsassertionsofaverydefinitecharacterrelatingtothesuccessionoflivingforms。Itisstatedthatplants，forexample，madetheirappearanceuponthethirdday，andnotbefore。Andyouwillunderstandthatwhatthepoetmeansbyplantsaresuchplantsasnowlive，theancestors，intheordinarywayofpropagationoflikebylike，ofthetreesandshrubswhichflourishinthepresentworld。Itmustneedsbeso；
for，iftheyweredifferent，eithertheexistingplantshavebeentheresultofaseparateoriginationsincethatdescribedbyMilton，ofwhichwehavenorecord，noranygroundforsuppositionthatsuchanoccurrencehastakenplace；orelsetheyhavearisenbyaprocessofevolutionfromtheoriginalstocks。
Inthesecondplace，itisclearthattherewasnoanimallifebeforethefifthday，andthat，onthefifthday，aquaticanimalsandbirdsappeared。Anditisfurtherclearthatterrestriallivingthings，otherthanbirds，madetheirappearanceuponthesixthdayandnotbefore。Hence，itfollowsthat，if，inthelargemassofcircumstantialevidenceastowhatreallyhashappenedinthepasthistoryoftheglobewefindindicationsoftheexistenceofterrestrialanimals，otherthanbirds，atacertainperiod，itisperfectlycertainthatallthathastakenplace，sincethattime，mustbereferredtothesixthday。
InthegreatCarboniferousformation，whenceAmericaderivessovastaproportionofheractualandpotentialwealth，inthebedsofcoalwhichhavebeenformedfromthevegetationofthatperiod，wefindabundantevidenceoftheexistenceofterrestrialanimals。Theyhavebeendescribed，notonlybyEuropeanbutbyyourownnaturalists。Therearetobefoundnumerousinsectsalliedtoourcockroaches。Therearetobefoundspidersandscorpionsoflargesize，thelattersosimilartoexistingscorpionsthatitrequiresthepractisedeyeofthenaturalisttodistinguishthem。InasmuchastheseanimalscanbeprovedtohavebeenaliveintheCarboniferousepoch，itisperfectlyclearthat，iftheMiltonicaccountistobeaccepted，thehugemassofrocksextendingfromthemiddleofthePalaeozoicformationstotheuppermostmembersoftheseries，mustbelongtothedaywhichistermedbyMiltonthesixth。
But，further，itisexpresslystatedthataquaticanimalstooktheiroriginonthefifthday，andnotbefore；hence，allformationsinwhichremainsofaquaticanimalscanbeprovedtoexist，andwhichthereforetestifythatsuchanimalslivedatthetimewhentheseformationswereincourseofdeposition，musthavebeendepositedduringorsincetheperiodwhichMiltonspeaksofasthefifthday。Butthereisabsolutelynofossiliferousformationinwhichtheremainsofaquaticanimalsareabsent。TheoldestfossilsintheSilurianrocksareexuviaeofmarineanimals；andiftheviewwhichisentertainedbyPrincipalDawsonandDr。CarpenterrespectingthenatureoftheEozoonbewell-founded，aquaticanimalsexistedataperiodasfarantecedenttothedepositionofthecoalasthecoalisfromus；inasmuchastheEozoonismetwithinthoseLaurentianstratawhichlieatthebottomoftheseriesofstratifiedrocks。Henceitfollows，plainlyenough，thatthewholeseriesofstratifiedrocks，iftheyaretobebroughtintoharmonywithMilton，mustbereferredtothefifthandsixthdays，andthatwecannothopetofindtheslightesttraceoftheproductsoftheearlierdaysinthegeologicalrecord。Whenweconsiderthesesimplefacts，weseehowabsolutelyfutilearetheattemptsthathavebeenmadetodrawaparallelbetweenthestorytoldbysomuchofthecrustoftheearthasisknowntousandthestorywhichMiltontells。Thewholeseriesoffossiliferousstratifiedrocksmustbereferredtothelasttwodays；andneithertheCarboniferous，noranyother，formationcanaffordevidenceoftheworkofthethirdday。
NotonlyistherethisobjectiontoanyattempttoestablishaharmonybetweentheMiltonicaccountandthefactsrecordedinthefossiliferousrocks，butthereisafurtherdifficulty。
AccordingtotheMiltonicaccount，theorderinwhichanimalsshouldhavemadetheirappearanceinthestratifiedrockswouldbethus：Fishes，includingthegreatwhales，andbirds；
afterthem，allvarietiesofterrestrialanimalsexceptbirds。
Nothingcouldbefurtherfromthefactsaswefindthem；weknowofnottheslightestevidenceoftheexistenceofbirdsbeforetheJurassic，orperhapstheTriassic，formation；
whileterrestrialanimals，aswehavejustseen，occurintheCarboniferousrocks。
IftherewereanyharmonybetweentheMiltonicaccountandthecircumstantialevidence，weoughttohaveabundantevidenceoftheexistenceofbirdsintheCarboniferous，theDevonian，andtheSilurianrocks。Ineedhardlysaythatthisisnotthecase，andthatnotatraceofbirdsmakesitsappearanceuntilthefarlaterperiodwhichIhavementioned。
Andagain，ifitbetruethatallvarietiesoffishesandthegreatwhales，andthelike，madetheirappearanceonthefifthday，weoughttofindtheremainsoftheseanimalsintheolderrocks——inthosewhichweredepositedbeforetheCarboniferousepoch。Fisheswedofind，inconsiderablenumberandvariety；
butthegreatwhalesareabsent，andthefishesarenotsuchasnowlive。NotonesolitaryspeciesoffishnowinexistenceistobefoundintheDevonianorSilurianformations。HenceweareintroducedafreshtothedilemmawhichIhavealreadyplacedbeforeyou：eithertheanimalswhichcameintoexistenceonthefifthdaywerenotsuchasthosewhicharefoundatpresent，arenotthedirectandimmediateancestorsofthosewhichnowexist；
inwhichcase，eitherfreshcreationsofwhichnothingissaid，oraprocessofevolution，musthaveoccurred；orelsethewholestorymustbegivenup，asnotonlydevoidofanycircumstantialevidence，butcontrarytosuchevidenceasexists。
Iplacedbeforeyouinafewwords，somelittletimeago，astatementofthesumandsubstanceofMilton’shypothesis。
Letmenowtrytostateasbriefly，theeffectofthecircumstantialevidencebearinguponthepasthistoryoftheearthwhichisfurnished，withoutthepossibilityofmistake，withnochanceoferrorastoitschieffeatures，bythestratifiedrocks。Whatwefindis，thatthegreatseriesofformationsrepresentsaperiodoftimeofwhichourhumanchronologieshardlyaffordusaunitofmeasure。Iwillnotpretendtosayhowweoughttoestimatethistime，inmillionsorinbillionsofyears。Formypurpose，thedeterminationofitsabsolutedurationiswhollyunessential。Butthatthetimewasenormoustherecanbenoquestion。
Itresultsfromthesimplestmethodsofinterpretation，thatleavingoutofviewcertainpatchesofmetamorphosedrocks，andcertainvolcanicproducts，allthatisnowdrylandhasoncebeenatthebottomofthewaters。Itisperfectlycertainthat，atacomparativelyrecentperiodoftheworld’shistory——theCretaceousepoch——noneofthegreatphysicalfeatureswhichatpresentmarkthesurfaceoftheglobeexisted。ItiscertainthattheRockyMountainswerenot。ItiscertainthattheHimalayaMountainswerenot。ItiscertainthattheAlpsandthePyreneeshadnoexistence。Theevidenceisoftheplainestpossiblecharacterandissimplythis：——Wefindraisedupontheflanksofthesemountains，elevatedbytheforcesofupheavalwhichhavegivenrisetothem，massesofCretaceousrockwhichformedthebottomoftheseabeforethosemountainsexisted。
ItisthereforeclearthattheelevatoryforceswhichgaverisetothemountainsoperatedsubsequentlytotheCretaceousepoch；
andthatthemountainsthemselvesarelargelymadeupofthematerialsdepositedintheseawhichonceoccupiedtheirplace。
Aswegobackintime，wemeetwithconstantalternationsofseaandland，ofestuaryandopenocean；and，incorrespondencewiththesealternations，weobservethechangesinthefaunaandfloratowhichIhavereferred。
Buttheinspectionofthesechangesgivesusnorighttobelievethattherehasbeenanydiscontinuityinnaturalprocesses。
Thereisnotraceofgeneralcataclysms，ofuniversaldeluges，orsuddendestructionsofawholefaunaorflora。
Theappearanceswhichwereformerlyinterpretedinthatwayhaveallbeenshowntobedelusive，asourknowledgehasincreasedandastheblankswhichformerlyappearedtoexistbetweenthedifferentformationshavebeenfilledup。Thatthereisnoabsolutebreakbetweenformationandformation，thattherehasbeennosuddendisappearanceofalltheformsoflifeandreplacementofthembyothers，butthatchangeshavegoneonslowlyandgradually，thatonetypehasdiedoutandanotherhastakenitsplace，andthatthus，byinsensibledegrees，onefaunahasbeenreplacedbyanother，areconclusionsstrengthenedbyconstantlyincreasingevidence。Sothatwithinthewholeoftheimmenseperiodindicatedbythefossiliferousstratifiedrocks，thereisassuredlynottheslightestproofofanybreakintheuniformityofNature’soperations，noindicationthateventshavefollowedotherthanaclearandorderlysequence。
That，Isay，isthenaturalandobviousteachingofthecircumstantialevidencecontainedinthestratifiedrocks。I
leaveyoutoconsiderhowfar，byanyingenuityofinterpretation，byanystretchingofthemeaningoflanguage，itcanbebroughtintoharmonywiththeMiltonichypothesis。
Thereremainsthethirdhypothesis，thatofwhichIhavespokenasthehypothesisofevolution；andIpurposethat，inlecturestocome，weshoulddiscussitascarefullyaswehaveconsideredtheothertwohypotheses。Ineednotsaythatitisquitehopelesstolookfortestimonialevidenceofevolution。Theverynatureofthecaseprecludesthepossibilityofsuchevidence，forthehumanracecannomorebeexpectedtotestifytoitsownorigin，thanachildcanbetenderedasawitnessofitsownbirth。Oursoleinquiryis，whatfoundationcircumstantialevidencelendstothehypothesis，orwhetheritlendsnone，orwhetheritcontrovertsthehypothesis。Ishalldealwiththematterentirelyasaquestionofhistory。Ishallnotindulgeinthediscussionofanyspeculativeprobabilities。IshallnotattempttoshowthatNatureisunintelligibleunlessweadoptsomesuchhypothesis。ForanythingIknowaboutthematter，itmaybethewayofNaturetobeunintelligible；sheisoftenpuzzling，andIhavenoreasontosupposethatsheisboundtofitherselftoournotions。
Ishallplacebeforeyouthreekindsofevidenceentirelybaseduponwhatisknownoftheformsofanimallifewhicharecontainedintheseriesofstratifiedrocks。Ishallendeavourtoshowyouthatthereisonekindofevidencewhichisneutral，whichneitherhelpsevolutionnorisinconsistentwithit。
Ishallthenbringforwardasecondkindofevidencewhichindicatesastrongprobabilityinfavourofevolution，butdoesnotproveit；and，lastly，Ishalladduceathirdkindofevidencewhich，beingascompleteasanyevidencewhichwecanhopetoobtainuponsuchasubject，andbeingwhollyandstrikinglyinfavourofevolution，mayfairlybecalleddemonstrativeevidenceofitsoccurrence。