CertainlyachildnewlyborninBoston，whogetsasensationfromthecandle-flamewhichlightsthebedroom，orfromhisdiaper-pin，doesnotfeeleitheroftheseobjectsto[p。35]besituatedinlongitude72°；W。andlatitude41°；N。Hedoesnotfeelthemtobeinthethirdstoryofthehouse。Hedoesnotevenfeeltheminanydistinctmannertobetotherightortheleftofanyoftheothersensationswhichhemaybegettingfromotherobjectsintheroomatthesametime。Hedoesnot，inshort，knowanythingabouttheirspace-relationstoanythingelseintheworld。Theflamefillsitsownplace，thepainfillsitsownplace；butasyettheseplacesareneitheridentifiedwith，nordiscriminatedfrom，anyotherplaces。Thatcomeslater。Fortheplacesthusfirstsensiblyknownareelementsofthechild’sspace-worldwhichremainwithhimallhislife；andbymemoryandlaterexperiencehelearnsavastnumberofthingsaboutthoseplaceswhichatfirsthedidnotknow。
　　Buttotheendoftimecertainplacesoftheworldremaindefinedforhimastheplaceswherethosesensationswere；andhisonlypossibleanswertothequestionwhereanythingiswillbetosay’there，’andtonamesomesensationorotherlikethosefirstones，whichshallidentifythespot。Spacemeansbuttheaggregateofallourpossiblesensations。
　　Thereisnoduplicatespaceknownaliunde，orcreatedbyan’epoch-makingachievement’intowhichoursensations，originallyspaceless，aredropped。
　　Theybringspaceandallitsplacestoourintellect，anddonotderiveitthence。
　　Byhisbody，then，thechildlatermeanssimplythatplacewherethepainfromthepin，andalotofothersensationslikeit，wereorarefelt。Itisnomoretruetosaythathelocatesthatpaininhisbody，thantosaythathelocateshisbodyinthatpain。Botharetrue:thatpainispartofwhathemeansbythewordbody。Justsobytheouterworldthechildmeansnothingmorethanthatplacewherethecandle-flameandalotofothersensationslikeitarefelt。Henomorelocatesthecandleintheouterworldthanhelocatestheouterworldinthecandle。Onceagain，hedoesboth；forthecandleispartofwhathemeansby’outerworld。’
　　Thisitseemstomewillbeadmitted，andwillItrustbemadestillmoreplausibleinthechapteronthePerceptionofSpace。Butthelaterdevelopmentsofthisperceptionaresocomplicatedthatthesesimpleprinciplesget[p。36]easilyoverlooked。Oneofthecomplicationscomesfromthefactthatthingsmove，andthattheoriginalobjectwhichwefeelthemtobesplitsintotwoparts，oneofwhichremainsastheirwhereaboutsandtheothergoesofastheirqualityornature。Wethencontrastwheretheywerewithwheretheyare。
　　Ifwedonotmove，thesensationofwheretheywereremainsunchanged；butweourselvespresentlymove，sothatthatalsochanges；
　　andIwheretheywere’becomesnolongertheactualsensationwhichitwasoriginally，butasensationwhichwemerelyconceiveaspossible。Graduallythesystemofthesepossiblesensations，takesmoreandmoretheplaceoftheactualsensations。’Up’and’down’become’subjective’notions；
　　eastandwestgrowmore’correct’than’right’and’left’etc。；andthingsgetatlastmore’truly’locatedbytheirrelationtocertainidealfixedco-ordinatesthanbytheirrelationeithertoourbodiesortothoseobjectsbywhichtheirplacewasoriginallydefined。Nowthisrevisionofouroriginallocalizationsisacomplexaffair；andcontainssomefactswhichmayverynaturallycometobedescribedastranslocationswherebysensationsgetshovedfartherofthantheyoriginallyappeared。
　　Fewthingsindeedaremorestrikingthanthechangeabledistancewhichtheobjectsofmanyofoursensationsmaybemadetoassume。Afly’shummingmaybetakenforadistantsteam-whistle；
　　ortheflyitself，seenoutoffocus，mayforamomentgiveustheillusionofadistantbird。Thesamethingsseemmuchnearerormuchfarther，accordingaswelookatthemthroughoneendoranother，ofanopera-glass。Ourwholeopticaleducationindeedislargelytakenupwithassigningtheirproperdistancestotheobjectsofourretinalsensations。Aninfantwillgraspatthemoon；later，itissaid，heprojectsthatsensationtoadistancewhichheknowstobebeyondhisreach。Inthemuchquotedcaseofthe’younggentlemanwhowasbornblind，’andwhowas’couched’forthecataractbyMr。Chesselden，itisreportedofthepatientthat"whenhefirstsaw，hewassofarfrommakinganyjudgmentaboutdistances，thathethoughtallobjectswhatevertouchedhiseyesasheexpresseditaswhat’hefeltdidhisskin。"Andotherpatientsbornblind，butrelievedbysurgicalop-[p。37]eration，havebeendescribedasbringingtheirhandclosetotheireyestofeelfortheobjectswhichtheyatfirstsaw，andonlygraduallystretchingouttheirhandwhentheyfoundthatnocontactoccurred。Manyhaveconcludedfromthesefactsthatourearliestvisualobjectsmustseeminimmediatecontactwithoureyes。
　　Buttactileobjectsalsomaybeaffectedwithalikeambiguityofsituation。
　　Ifoneofthehairsofourheadbepulled，weareprettyaccuratelysensibleofthedirectionofthepullingbythemovementsimpartedtothehead。[45]Butthefeelingofthepullislocalized，notinthatpartofthehair’slengthwhichthefingershold，butinthescalpitself。Thisseemsconnectedwiththefactthatourhairhardlyservesatallasatactileorgan。Increatureswithvibrisse，however，andinthosequadrupedswhosewhiskersaretactileorgans，itcanhardlybedoubtedthatthefeelingisprojectedoutoftherootintotheshaftofthehairitself。Weourselveshaveanapproachtothiswhenthebeardasawhole，orthehairasawhole，istouched。Weperceivethecontactatsomedistancefromtheskin。
　　Whenfixedandhardappendagesofthebody，liketheteethandnails，aretouched，wefeelthecontactwhereitobjectivelyis，andnotdeeperin，wherethenerve-terminationslie。If，however，thetoothisloose，wefeeltwocontacts，spatiallyseparated，oneatitsroot，oneatitstop。
　　Fromthiscasetothatofahardbodynotorganicallyconnectedwiththesurface，butonlyaccidentallyincontactwithit，thetransitionisimmediate。Withthepointofacanewecantracelettersintheairoronawalljustaswiththefinger-tip；andinsodoingfeelthesizeandshapeofthepathdescribedbythecane’stipjustasimmediatelyas，withoutacane，weshouldfeelthepathdescribedbythetipofourfinger。Similarlythedraughtsman’simmediateperceptionseemstobeofthepointofhispencil，thesur-[p。38]geon’softheendofhisknife，theduellist’softhetipofhisrapierasitplungesthroughhisenemy’sskin。Whenonthemiddleofavibratingladder，wefeelnotonlyourfeetontheround，buttheladder’sfeetagainstthegroundfarbelow。Ifweshakealockedirongatewefeelthemiddle，onwhichourhandsrest，move，butweequallyfeelthestabilityoftheendswherethehingesandthelockare，andweseemtofeelallthreeatonce。
　　[46]Andyettheplacewherethecontactisreceivedisinallthesecasestheskin，whosesensationsaccordinglyaresometimesinterpretedasobjectsonthesurface，andatothertimesasobjectsalongdistanceoff。
　　WeshalllearninthechapteronSpacethatourfeelingsofourownmovementareprincipallyduetothesensibilityofourrotatingjoints。Sometimesbyfixingtheattention，sayonourelbow-joint，wecanfeelthemovementinthejointitself；butwealwaysaresimultaneouslyconsciousofthepathwhichduringthemovementourfinger-tipsdescribethroughtheair，andyetthesesamefinger-tipsthemselvesareinnowayphysicallymodifiedbythemotion。Ablowonourulnarnervebehindtheelbowisfeltboththereandinthefingers。Refrigerationoftheelbowproducespaininthefingers。Electriccurrentspassedthroughnerve-trunks，whetherofcutaneousorofmorespecialsensibilitysuchastheopticnerve，giverisetosensationswhicharevaguelylocalizedbeyondthenerve-tractstraversed。Personswhoselegsorarmshavebeenamputatedare，asiswellknown，apttopreserveanillusoryfeelingofthelosthandorfootbeingthere。Evenwhentheydonothavethisfeelingconstantly，itmaybeoccasionallybroughtback。Thissometimesistheresultofexcitingelectricallythenerve-trunksburiedinthestump。
　　"Irecentlyfaradized，"saysDr。Mitchell，"acaseofdisarticulatedshoulderwithoutwarningmypatientofthepossibleresult。Fortwoyearshehadaltogetherceasedtofeelthelimb。Asthecurrentaffectedthebrachialplexusofnerveshesuddenlycriedaloud，’Ohthehand，——thehand！’andattemptedtoseizethemissingmember。
　　Thephantom[p。39]Ihadconjuredupswiftlydisappeared，butnospiritcouldhavemoreamazedtheman，sorealdiditseem。"[47]
　　Nowtheapparentpositionofthelostextremityvaries。Oftenthefootseemsontheground，orfollowsthepositionoftheartificialfoot，whereoneisused。Sometimeswherethearmislosttheelbowwillseembent，andthehandinafixedpositiononthebreast。
　　Sometimes，again，thepositionisnon-natural，andthehandwillseemtobudstraightoutoftheshoulder，orthefoottobeonthesamelevelwiththekneeoftheremainingleg。Sometimes，again，thepositionisvague；
　　andsometimesitisambiguous，asinanotherpatientofDr。WeirMitchell’swho"losthislegattheageofeleven，andremembersthatthefootbydegreesapproached，andatlastreachedtheknee。Whenhebegantowearanartificiallegitreassumedintimeitsoldposition，andheisneveratpresentawareofthelegasshortened，unlessforsometimehetalksandthinksofthestump，andofthemissingleg，when……thedirectionofattentiontothepartcausesafeelingofdiscomfort，andthesubjectivesensationofactiveandunpleasantmovementofthetoes。Withthesefeelingsreturnsatoncethedelusionofthefootasbeingplacedattheknee。"
　　Allthesefacts，andotherslikethem，caneasilybedescribedasifoursensationsmightbeinducedbycircumstancestomigratefromtheiroriginallocalitynearthebrainornearthesurfaceofthebody，andtoappearfartheroff；andundercurrentcircumstances
　　toreturnagainafterhavingmigrated。Butalittleanalysisofwhathappensshowsusthatthisdescriptionisinaccurate。
　　Theobjectivitywithwhicheachofoursensationsoriginallycomestom，theroomyandspatialcharacterwhichisaprimitivepartofitscontent，isnotinthefirstinstancerelativetoanyothersensation。Thefirsttimeweopenoureyeswegetanopticalobjectwhichisaplace，butwhichisnotyetplacedinrelationtoanyotherobject，noridentifiedwithanyplaceotherwiseknown。Itisaplacewithwhichsofarweareonlyacquainted。Whenlaterweknowthatthissameplaceisin’front’ofus，thatonlymeansthatwehavelearnedsomethingaboutit，namely，thatitiscongruentwiththat[p。40]otherplace，called’front，’whichisgivenusbycertainsensationsofthearmandhandoroftheheadandbody。Butatthefirstmomentofouropticalexperience，eventhoughwealreadyhadanacquaintancewithourhead，hand，andbody，wecouldnotpossiblyknowanythingabouttheirrelationstothisnewseenobject。Itcouldnotbeimmediatelylocatedinrespectofthem。Howitsplaceagreeswiththeplaceswhichtheirfeelingsyieldisamatterofwhichonlylaterexperiencecaninformus；andinthenextchapterweshallseewithsomedetailhowlaterexperiencedoesthisbymeansofdiscrimination，association，selection，andotherconstantlyworkingfunctionsofthemind。When，therefore，thebabygraspsatthemoon，thatdoesnotmeanthatwhatheseesfailstogivehimthesensationwhichlieafterwardsknowsasdistance；itmeansonlythathehasnotlearnedatwhattactileormanualdistancethingswhichappearatthatvisualdistancesare。[48]Andwhenapersonjustoperatedforcataractgropesclosetohisfaceforfar-offobjects，thatonlymeansthesamething。Alltheordinaryopticalsignsofdifferingdistancesareabsentfromthepoorcreature’ssensationanyhow。
　　Hisvisionismonocularonlyoneeyebeingoperatedatatime；thelensisgone，andeverythingisoutoffocus；hefeelsphotophobia，lachrymation，andotherpainfulresidentsensationsoftheeyeballitself，whoseplacehehaslongsincelearnedtoknowintactileterms；whatwonder，then，thatthefirsttactilereactionwhichthenewsensationsprovokeshouldbeoneassociatedwiththetactilesituationoftheorganitself？Andasforhisassertionsaboutthematter，whatwonder，again，if，asProf。PaulJanetsays，theyarestillexpressedinthetactilelanguagewhichistheonlyoneheknows。"Tobetouchedmeansforhimtoreceiveanimpressionwithoutfirstmakingamovement。"Hiseyegetssuchanimpressionnow；
　　sohecanonlysaythattheobjectsaretouchingit。’
　　"Allhislanguage，borrowedfromtouch，butappliedtotheobjectsofhissight，makeusthinkthatheperceivesdifferentlyfromourselves，[p。41]whereas，atbottom，itisonlyhisdifferentwayoftalkingaboutthesameexperience。[49]
　　Theothercasesoftranslocationofoursensationsareequallyeasilyinterpretedwithoutsupposingany’projection’
　　fromacentreatwhichtheyareoriginallyperceived。Unfortunatelythedetailsareintricate；andwhatIsaynowcanonlybemadefullyclearwhenwecometothenextchapter。Weshallthenseethatweareconstantlyselectingcertainofoursensationsasrealitiesanddegradingotherstothestatusofsignsofthese。Whenwegetoneofthesignswethinkoftherealitysignified；andthestrangethingisthatthentherealitywhichneednotbeitselfasensationatallatthetime，butonlyanideaissointerestingthatitacquiresanhallucinatorystrength，whichmayeveneclipsethatoftherelativelyuninterestingsignandentirelydivertourattentionfromthelatter。Thusthesensationstowhichourjointsgiverisewhentheyrotatearesignsofwhat，throughalargenumberofothersensations，tactileandoptical，wehavecometoknowasthemovementofthewholelimb。Thismovementofthewholelimbiswhatwethinkofwhenthejoint’snervesareexcitedinthatway；anditsplaceissomuchmoreimportantthanthejoint’splacethatoursenseofthelatteristakenup，sotospeak，intoourperceptionoftheformer，andthesensationofthemovementseemstodiffuseitselfintoourveryfingersandtoes。Butbyabstractingourattentionfromthesuggestionoftheentireextremitywecanperfectlywellperceivethesamesensationasifitwereconcentratedinonespot。Wecanidentifyitwithadifferentlylocatedtactileandvisualimageof’thejoint’itself。
　　Justsowhenwefeelthetipofourcaneagainsttheground。Thepeculiarsortofmovementofthehandimpossibleinonedirection，butfreeineveryotherwhichweexperiencewhenthetiptouches’theground，’isasigntousofthevisualandtactileobjectwhichwealready[p。42]knowunderthatname。Wethinkof’theground’
　　asbeingthereandgivingusthesensationofthiskindofmovement。Thesensation，wesay，comesfromtheground。Theground’splaceseemstobeitsplace；althoughatthesametime，andforverysimilarpracticalreasons，wethinkofanotheropticalandtactileobject，’thehand’namely，andconsiderthatitsplacealsomustbetheplaceofoursensation。
　　Inotherwords，wetakeanobjectorsensiblecontentA，andconfoundingitwithanotherobjectotherwiseknown，B，orwithtwoobjectsotherwiseknown，BandC，weidentifyitsplacewiththeirplaces。Butinallthisthereisno’projecting’suchastheextradition-philosopherstalkofofAoutofanoriginalplace；noprimitivelocationwhichitfirstoccupied，awayfromtheseothersensations，hastobecontradicted；
　　nonatural’centre，’fromwhichitisexpelled，exists。ThatwouldimplythatAaboriginallycametousindefinitelocalrelationswithothersensations，fortobeoutofBandCistobeinlocalrelationwiththemasmuchastobeinthemisso。ButitwasnomoreoutofBandCthanitwasinthemwhenitfirstcametous。Itsimplyhadnothingtodowiththem。Tosaythatwefeelasensation’sseattobe’inthebrain’or’againsttheeye’
　　or’undertheskin’istosayasmuchaboutitandtodealwithitinasnon-primitiveawayastosaythatitisamileoff。Theseareallsecondaryperceptions，waysofdefiningthesensation’sseatperaliud。Theyinvolvenumberlessassociations，identifications，andimaginations，andadmitagreatdealofvacillationanduncertaintyintheresult。[50]
　　Iconclude，then，thatthereisnotruthinthe’eccentricprojection’theory。Itisduetotheconfusedassumptionthatthebodilyprocesseswhichcauseasensationmustalsobeitsseat。
　　[51]Butsensationshavenoseatinthissense。They[p。43]becomeseatsforeachother，asfastasexperienceassociatesthemtogether；butthatviolatesnoprimitiveseatpossessedbyanyoneofthem。Andthoughoursensationscannotthensoanalyzeandtalkofthemselves，yetattheirveryfirstappearancequiteasmuchasatanylaterdatearetheycognizantofallthosequalitieswhichweendbyextractingandconceivingunderthenamesofobjectivity，exteriority，andextent。Itissurelysubjectivityandinferioritywhicharethenotionslatestacquiredbythehumanmind。[52]
　　[1]Somepersonswillsaythatweneverhaveareallysimpleobjectorcontent。Mydefinitionofsensationdoesnotrequirethesimplicitytobeabsolutely，butonlyrelatively，extreme。Itisworthwhileinpassing，however，towarnthereaderagainstacoupleofinferencesthatareoftenmade。Oneisthatbecausewegraduallylearntoanalyzesomanyqualitiesweoughttoconcludethattherearenoreallyindecomposablefeelingsinthemind。Theotheristhatbecausetheprocessesthatproduceoursensationsaremultiple，thesensationsregardedassubjectivefactsmustalsobecompound。Totakeanexample，toachildthetasteoflemonadecomesatfirstasasimplequality。Helaterlearnsboththatmanystimuliandmanynervesareinvolvedintheexhibitionofthistastetohiswind，andhealsolearnstoperceiveseparatelythesourness，thecoolness，thesweet，thelemonaroma，etc。，andtheseveraldegreesofstrengthofeachandallofthesethings，——
　　theexperiencefallingintoalargenumberofaspects，eachofwhichisabstracted，classed，named，etc。，andallofwhichappeartobetheelementarysensationsintowhichtheoriginal’lemonadeflavor’isdecomposed。Itisarguedfromthisthatthelatterneverwasthesimplethingwhichitseemed。IhavealreadycriticisedthissortofreasoninginChapterVIseepp。17ff。。Themindofthechildenjoyingthesimplelemonadeflavorandthatofthesamechildgrownupandanalysingitareintwoentirelydifferentconditions。Subjectivelyconsidered，thetwostatesofmindaretwoaltogetherdistinctsortsoffact。Thelatermentalstatesays’thisisthesameflavororfluidwhichthatearlierstateperceivedassimple，butthatdoesnotmakethetwostatesthemselvesidentical。Itisnothingbutacaseoflearningmoreandmoreaboutthesametopicsofdiscourseorthings——Manyofthesetopics，however，mustbeconfessedtoresistallanalysis，thevariouscolorsforexample。Hewhoseesblueandyellow’in’acertaingreenmeansmerelythatwhengreenisconfrontedwiththeseothercolorsheseesrelationsofsimilarity。Hewhoseesabstract’color’initmeansmerelythatheseesasimilaritybetweenitandalltheotherobjectsknownascolors。Similarityitselfcannotultimatelybeaccountedforbyanidenticalabstractelementburiedinallthesimilars，ashasbeenalreadyshown，p。492ff。Hewhoseesabstractpaleness，intensity，purity，inthegreenmeansothersimilaritiesstill。Thesearealloutwarddeterminationsofthatspecialgreen，knowledgesaboutit，zü；alligeAnischten，asHerbartwouldsay，notelementsofitscomposition。
　　ComparethearticlebyMeinongintheVierteliahrschriftfü；rwiss。
　　Phil。，xii。324。
　　[2]Seeabove，p。221
　　[3]ThosewhowishafullertreatmentthanMartin’sHumanBodyaffordsmayberecommendedtoBernstein’s’FiveSensesofMan，’intheInternationalScientificSeries，ortoLadd’sorWundt’sPhysiologicalPsychology。ThecompletestcompendiumisL。Hermann’sHandbuchderPhysiologie，Vol。III。
　　[4]"Thesensationswhichwepostulate，asthesignsoroccasionsofourperceptions"A。Seth:ScottishPhilosophy，p。89。"Theirexistenceissupposedonlybecause，withoutthem，itwouldbeimpossibletoaccountforthecomplexphenomenawhicharedirectlypresentinconsciousness"J。Dewey:Psychology，p。34。EvenasgreatanenemyofSensationasT。H。Greenhastoallowitasortofhypotheticalexistenceunderprotest。"Perceptionpresupposesfeeling"
　　Contemp。Review，vol。xxxi。p。747。Cf。alsosailpassagesasthoseinhisProlegomenatoEthics，§；§；48，49——Physiologically，thesensoryandthereproductiveorassociativeprocessesmaywaxandwaneindependentlyofeachother。Wherethepartdirectlyduetostimulationofthesense-organpreponderates，thethoughthasasensationalcharacter，anddiffersfromotherthoughtsinthesensationaldirection。Thosethoughtswhichliefarthestinthatdirectionwecallsensations，forpracticalconvenience，justaswecallconceptionsthosewhichlienearertheoppositeextreme。Butwenomorehaveconceptionspurethanwehavepuresensations。Ourmostrarefiedintellectualstatesinvolvesomebodilysensibility，justasourdullestfeelingshavesomeintellectualscope。
　　Common-senseandcommonpsychologyexpressthisbysayingthatthementalstateiscomposedofdistinctfractionalparts，oneofwhichIssensation，theotherconception。We，however，whobelieveeverymentalstatetobeanintegralthingp。276cannottalkthus，butmustspeakofthedegreeofsensationalorintellectualcharacter，orfunction，ofthementalstate。ProfessorHeringputs，asusual，hisfingerbetteruponthetruththananyoneelse。Writingofvisualperception，hesays:"Itisinadmissibleinthepresentstateofourknowledgetoassertthatfirstandlastthesameretinalpicturearousesexactlythesamepuresensation，butthatthissensation，inconsequenceofpracticeandexperience，isdifferentlyinterpretedthelasttime，andelaboratedintoadifferentperceptionthefirst。Fortheonlyrealdataare，ontheonehand，thephysicalpictureontheretina，——andthatisbothtimesthesame；and，ontheotherhand，theresultantstateofconsciousnessausgelö；steEmpfindungscomplex——andthatisbothtimesdistinct。Ofanythirdthing，namely，apuresensationthrustbetweentheretinalandthementalpictures，weknownothing。Wecanthen，ifwewishtoavoidallhypothesis，onlysaythatthenervousapparatusreactsuponthesamestimulusdifferentlythelasttimefromthefirst，andthatinconsequencetheconscioussisdifferenttoo。"Hermann’sHdbch。，iii。i。567-8。
　　[5]YetevenwriterslikeProf。Bainwilldeny，inthemostgratuitousway，thatsensationsknowanything。"Itisevidentthatthemostrestrictedformofsensationdoesnotcontainanelementedge。Themerestateofmindcalledthesensationofscarletisedge，althoughanecessarypreparationforit。"’Isnotknowaboutscarlet’isallthatProfessorBaincanrightfullysay。
　　[6]BysimpleideasofsensationLockemerelymeanssensations。
　　[7]Essayc。H。U。，bk。
　　ii。ch。xxiii。§；29；ch。xxv。§；9。
　　[8]Classicseditor’snote:James’insertion。
　　[9]Op。cit。Bk。
　　Iich。ii§；2。
　　[10]"Sofarisitfrombeingtruethatwenecessarilyhaveasmanyfeelingsinconsciousnessatonetimeasthereareislestothesensethenplayedupon，thatitisafundamentallawofpuresensationthateachmomentarilystateoftheorganismyieldsbutonefeeling，howevernumerousmaybeItspartsanditsexposures……TothisoriginalUnityofconsciousnessitmakesnodifferencethatthetributariestothesinglefeelingarebeyondtheorganisminsteadofwithinit，inanoutsideobjectwithseveralsensibleproperties，insteadofinthelivingbodywithitsseveralsensitivefunctions……Theunitythereforeisriotmadeby’association’ofseveralcomponents；butthepluralityisformedbydissociationofunsuspectedvarietieswithintheunity；thesubstantivethingbeingnoproductofsynthesis，buttheresiduumofdifferentiation。"J。Martineau:AStudyofReligion1888，p。192-4。ComparealsoF。H。Bradley，Logic，booki。chap。ii。
　　[11]Suchpassagesasthefollowingaboundinanti-sensationalistliterature:
　　"Senseisakindofdull，confused，andstupidperceptionobtrudeduponthesoulfromwithout，wherebyitperceivesthealterationsandmotionswithinitsownbody，andtakescognizanceofindividualbodiesexistingroundaboutit，butdoesnotclearlycomprehendwhattheyarenorpenetrateintothenatureofthem，itbeingintendedbynature，asPlotinusspeaks，notsoproperlyforknowledgeasfortheuseofthebody。Forthesoulsufferingunderthatwhichitperceivesbywayofpassioncannotmasterorconquerit，thatistosay，knoworunderstandit。ForsoAnaxigorasinAristotleveryfairlyexpressesthenatureofknowledgeandintellectionunderthenotionofConquering。Whereforeitisnecessary，sincethemindunderstandsallthings，thatitshouldbefreefrommixtureandpassion，forthisend，asAnaxagoriasspeaks，thatitmaybeabletoknowandmasterandconqueritsobjects，thatistosay，toconquerandunderstandthem。InlikemannerPieus，inhisbookofSenseandMemory，makestosufferandtobe，conquered:
　　one，alsotoknowandtoconquer；forwhichreasonheconcludesthatthatwhichsuffersdothnotknow……Sensethatsuffersfromexternalobjectsliesasitwereprostrateunderthem，andisovercomebythem……Sensethereforeisacertainkindofdrowsyandsomnolentperceptionofthatpassivepartofthesoulwhichisasitwereasleepandactsconcretelywithit……Itisanenergyarisingfromthebodyandacertainkindofdrowsyorsleepinglifeofthesoulblendedtogetherwithit。Theperceptionsofwhichcompound，orofthesoulasitwerehalfasleepandhalfawake，areconfused，indistinct，turbid，andencumberedcogitationsverydifferentfromtheenergiesofthenoeticalpart，……whicharefree，clear，serene，satisfactory，andawakenedcogitations。Thatistosay，knowledges"Etc。，etc。，etc。R。Cudworth:TreatiseconcerningEternalandImmutableMorality，bkiii。chap。ii。SimilarlyMalbranche:"THÉ；ODORE——Oh，oh，Ariste！Godknowspain，pleasureandtherest。Buthedoesnotfeelthesethings。Heknowspain，sinceheknowswhatthatmodificationofthesoulisinwhichpainconsists。HeknowsitbecausehealonecausesitinusasIshallpresentlyprove，andheknowswhathedoes。Inaword，heknowsitbecausehisknowledgehasnobounds。Buthedoesnotfeelit，forifsohewouldbeunhappy。Toknowpain，then，isnottofeelit。ARISTE——
　　Thatistrue。Buttofeelitistoknowit，isitnot？THÉ；ODORE——
　　Noindeed，sinceGoddoesnotfeelitintheleast，andyetheknowsitperfectly。Butinordernottoquibbleaboutterms，ifyouwillhaveitthattofeelpainistoknowit，agreeathatitisnottoknowitclearly，thatitisnottoknowitbylightanbyevidence——inaword，thatitisnottoknowitsnature；inotherwordsspeakexactly，itisnottoknowitatall。Tofeelpain，forexample，istofeelourselvesunhappywithoutwellknowingeitherwhatweareoristhismodalityofourbeingwhichmakesusunhappy……Imposesilenceonyoursenses，yourimagination，andyourpassions，andyouwillhearthepurevoiceofinnertruth，theclearandevidentrepliesofourcommonmaster。Neverconfoundtheevidencewhichresultsfromthecomparisonofideaswiththelivelinessofthesensationswhichtouchandthrillyou。Thelivelieroursensationsandfeelingssentiments
　　are，themoredarknessdotheyshed。Themoreterribleoragreeableareourphantoms，andtheybodyandrealitytheyappeartohave，themoredangerousaretheyantoleadusastray。"EntretienssurlaMé；taphysique，3meEntretienadinit。Malebranche’sTheodoreprudentlydoesnottrytoexplainGod’s’infinitefelicity’iscompatiblewithhisnotfeelingjoy。
　　[12]Green:Prolegomena，§；§；20，28。
　　[13]Introd。toHume，§；§；146，188。Itishardtotelljustwhatthisapostolichumanbeingbutstrenuouslyfeeblewritermeansbyrelation。Sometimesitseemstostandforsystemofrelatedfact。Theubiquityofthe’psychologist’sfallacy’seep。196inhispages，hisincessantleaningontheconfusionbetweenthethingknown，thethoughtthatknowsit，andthefartherthingsknownaboutthatthingandaboutthatthoughtbylaterandadditionalthoughts，makeitimpossibletoclearuphismeaning。Compare，however，utterancesinthetextsuchothersasthese:"ThewakingofSelf-consciousnessfromthesleepofsenseisanabsolutenewbeginning，andnothingcancomewithinthe’crystalsphere’ofintelligenceexceptasitisdeterminedbyintelligence。
　　Whatsenseistosenseisnothingforthought。Whatsenseistothought，itisasdeterminedbythought。Therecan，therefore，beno’reality’insensationtowhichtheworldofthoughtcanbereferred。"EdwardCaird’sPhilosophyofKant，1sted。pp。393-4。"When，"saysGreenagain，"feelingapainorpleasureofheattobeconnectedwiththeactionofapproachingthefire，amInotreceivingarelationofwhichoneconstituent，atanyrate，isasimplesensation？ThetrueanswerisNo。""Perception，initssimplestform——perceptionasthefirstsightortouchofanobjectinwhichisseenortouchedisrecognized——neitherisnorcontainssensation。Contemp。Rev。，xxxi。pp。746，750。"Meresensationisintruthaphrasethatrepresentsnoreality。""Merefeeling，then，asamatterunformedbythought，hasnoplaceintheworldoffacts，inthecosmosofpossibleexperience。"ProglegomenatoEthics，§；§；
　　46，50。——Ihaveexpressedmyselfalittlemorefullyonthissubjectinmind，x。27ff。
　　[14]Stumpf:Tonpsychologie，i。Pp。7，8。Hobbes’sphrase，sentiresemperidemetnonsentireadidemrecidunt，isgenerallytreatedastheoriginalstatementoftherelativitydoctrine。J。S。MillExamn。ofHamilton，p。6andBainSensesandIntellect。
　　p。321；EmotionsandWill，pp。550，570-2；Logic，i。p。2；BodyandMind，p。81aresubscriberstothisdoctrinealsoJ。S。Mill’sanalysis，J。
　　S。Mill’sedition，ii。11，12。
　　[15]Wecansteadilyhearanoteforhalfanhour。Thedifferencebetweenthesensesaremarked。
　　Smellandtasteseemsoontogetfatigued。
　　[16]Inthepopularminditismixedupwiththatentirelydifferentdoctrineofthe’RelativityofKnowledge’preachedbyHamiltonandSpencer。Thisdoctrinesaysthatourknowledgeisrelativetous，andisnotoftheobjectasthelatterisinitself。Ithasnothingtodowiththequestionwhichwehavebeendiscussing，ofwhetherourobjectsofknowledgecontainabsolutetermsorconsistaltogetherofrelations。
　　[17]Whatfollowsinbrackets，asfarasp。27，isfromthepenofmyfriendandpupilMr。E。
　　B。Delabarre。
　　[18]Classicseditor’snote:James’insertion。
　　[19]Thesephenomenahavecloseanaloguesinthephenomenaofcontrastpresentedbythetemperature-senseseeW。PreyerinArchivf。d。gesPhys。，Bd。xxv。p。79ff。。Successivecontrasthereisshowninthefactthatawarmsensationappearswarmerifacoldonehasjustpreviouslybeenexperienced；andacoldonecolder，iftheprecedingonewaswarm。Ifafingerwhichhasbeenplungedinhotwater，andanotherwhichhasbeenincoldwater，bebothimmersedinlukewarmwater，thesamewaterappearscoldtotheformerfingerandwarmtothelatter。Insimultaneouscontrast，asensationofwarmthonanypartoftheskintendstoinducethesensationofcoldinitsimmediateneighborhood；
　　andviceversá；。Thismaybeseenifwepresswiththepalmontwometalsurfacesofaboutinchandahalfsquareandthree-fourthsinchapart；
　　theskinbetweenthemappearsdistinctlywarmer。Soalsoasmallobjectofexactlythetemperatureofthepalmappearswarmifacoldobject，andcoldifawarmobject，touchtheskinnearit。
　　[20]Helmholtz，Physiolog。
　　Optik，p。392。
　　[21]Loc。cit。
　　p。407。
　　[22]Loc。cit。
　　p。408。
　　[23]Loc。cit。
　　p。406。
　　[24]E。Hering，inHermann’sHandbuchd。Physiologie，iii。1，p。565。
　　[25]Hering:’ZurLehrevomLichtsinne。’——Oftheseexperimentsthefollowingfoundonp。24
　　ff。maybecitedasatypicalone:"Fromdarkgraypapercuttwostrips3-4cm。longand½；cm。wide，andlaythemonabackgroundofwhichonehalfiswhiteandtheotherhalfdeepblack，insuchawaythatonestripliesoneachsideoftheborder-lineandparalleltoit，andatleast1cm。distantfromit。Fixate½；to1minuteapointontheborder-linebetweenthestrips。Onestripappearsmuchbrighterthantheother。Closeandcovertheeyes，andthenegativeafter-imageappears……Thedifferenceinbrightnessofthestripsintheafter-imageisingeneralmuchgreaterthanitappearedindirectvision……Thisdifferenceinbrightnessofthestripsbynomeansalwaysincreasesanddecreaseswiththedifferenceinbrightnessofthetwohalvesoftilebackground……phaseoccursinwhichthedifferenceinbrightnessofthetwohalvesthebackgroundentirelydisappears，andyetbothafter-imagesofthestripsarestillveryclear，oneofthembrighterandonedarkerthanthebackground，whichisequallybrightonbothhalves。Herecannolongerbeanyquestionofcontrast-effect，becausetheconditiosinequanonofcontrast，namely，thedifferingbrightnessoftheground，isnolongerpresent。Thisprovesthatthedifferentbrightnessoftheafter-imagesofthestripsmusthaveitsgroundinadifferentstateofexcitationofthecorrespondingportionsoftheretina，andfromthisfollowsfurtherthatboththeseportionsoftheretinaweredifferentlystimulatedduringtheoriginobservation；
　　forthedifferentafter-effectdemandshereadifferenteffect……Intheoriginalarrangement，theobjectivelysimilarstripsappearedofdifferentbrightness，becausebothcorrespondingportionsretinaweretrulydifferentlyexcited。"
　　[26]Helmholtz，Physiolog。
　　Optik，p。407。
　　[27]InArchivf。d。
　　ges。Physiol。，Bd。XLI。S。1ff。
　　[28]Helmholtz，loc。
　　cit。p。412。
　　[29]SeeHering:Archiv。
　　f。d。ges。Physiol。，Bd。XLI。S。358ff。
　　[30]Hering:Archivf。d。ges。Physiol。，Bd。XL。B。172ff。；Delabarre:AmericanJournalofPsychology，ii。636。
　　[31]Hering:Archivf。d。ges。Physiol。，Bd。XLI。S。91ff。
　　[32]DieGesichtsempfindungenu。ihreAnalyse，p。128。
　　[33]Classicseditor’snote:James’insertion。
　　[34]Mr。Delabarre’scontributionendshere。
　　[35]Physiol。Psych。，i。351，458-60。ThefullinanityofthelawofrelativityisbesttobeseeninWundt’streatment，wherethegreat’allgemeinerGesetzderBeziehung，’invokedtoaccountforWeber’slawaswellasforthephenomenaofcontrastandmanyothermatters，canonlybedefinedasatendencytofeelallthingsinrelationtoeachother！Blessitslittlesoul！Butwhydoesitchangethethingsso，whenitthusfeelstheminrelation？
　　[36]Ladd:Physiol。
　　Psych。，p。348。
　　[37]Mind，x。567。
　　[38]Zwangsmä；ssigeLichtempfindungdurchSchallLeipzig，1881。
　　[39]Ptlü；ger’sArchiv，XLII。154。
　　[40]Classicseditor’snote:James’insertion。
　　[41]PhysiologicalPsychology，385，387。SeealsosuchpassagesasthatinBain:TheSensesandtheIntellect，pp。364-6。
　　[42]Especiallymustweavoidallattempts，whetheravowedorconcealed，toaccountforthespatialqualitiesofthepresentationsofsensebymerelydescribingthequalitiesofthesimplesensationsandthemodesoftheircombination。
　　Itispositionandextensioninspacewhichconstitutestheverypeculiarityoftheobjectsasnolongermeresensationsoraffectionsofthemind。Assensations，theyareneitheroutofourselvesnorpossessedofthequalitiesindicatedbythewordspread-out。"Ladd，op。cit。p。
　　391。
　　[43]A。Riehl:DerPhilosophischerKriticismus，Bd。ii。Theilii。p。64。
　　[44]OnIntelligence，partii。bk。ii。chap。ii。§；§；vii，viii。Comparesuchstatementsasthese:"TheconsequenceisthatwhenasensationhasforItsusualconditionthepresenceofanobjectmoreorlessdistantfromourbodies，andexperiencehasoncemadeusacquaintedwiththisdistance，weshallsituateoursensationatthisdistance——This，infact，isthecasewithsensationsofhearingandsight。Theperipheralextremityoftheacousticnerveisinthedeep-seatedchamberofthecar。Thatoftheopticnerveisinthemostinnerrecessoftheeye。Butstill，inourpresentstate，weneversituateoursensationsofsoundorcolorintheseplaces，butwithoutus，andoftenataconsiderabledistancefromus……Alloursensationsofcolorarethusprojectedoutofourbody，andclothemoreorlessdistantobjects，furniture，walls，houses，trees，thesky，andtherest。Thisiswhy，whenweafterwardsreflectonthem，weceasetoattributethemtoourselves；theyarealienatedanddetachedfromus，sofarastoappeardifferentfromus。Projectedfromthenervoussurfaceinwhichwelocalizethemajorityoftheothers，thetiewhichconnectedthemtotheothersandtoourselvesisundone……Thus，alloursensationsarewronglysituated，andtheredcolorisnomoreextendedonthearm-chairthanthesensationoftinglingissituatedatmyfingers’ends。Theyareallsituatedinthesensorycentresoftheencephalon；allappearsituatedelsewhere，andacommonlawallotstoeachofthemitsapparentsituation。"Vol。ii。pp。47-53。——SimilarlySchopenhauer:
　　"Iwillnowshowthesamebythesenseofsight。Theimmediatedatumisherelimitedtothesensationoftheretinawhich，itistrue，admitsofconsiderablediversity，butatbottomrevertstotheimpressionoflightanddarkwiththeirshades，andthatofcolors。Thissensationisthroughandthroughsubjective，thatis，insideoftheorganismandundertheskin。"
　　Schopenhauer:SatzvomGrunde，p。58。ThisphilosopherthenenumeratesseriatimwhattheIntellectdoestomaketheoriginallysubjectivesensationobjective:1itturnsitbottomsideup；2itreducesitsdoublenesstosingleness；3itchangesitsflatnesstosolidity；and4itprojectsittoadistancefromtheeye。Again:"Sensationsarewhatwecalltheimpressionsonoursenses，insofarastheycometoourconsciousnessasstatesofourownbody，especiallyofournervousapparatus；wecallthemperceptionswhenweformoutofthemtherepresentationofouterobjects。"Helmholtz:Tonempfindungen，1870，p。101。——Oncemore:
　　"Sensationisalwaysaccomplishedinthepsychiccentres，butitmanifestsitselfattheexcitedpartoftheperiphery。Inotherwords，oneisconsciousofthephenomenoninthenervouscentres……butoneperceivesitintheperiphericorgans。Thisphenomenondependsontheexperienceofthesensationsthemselves，inwhichthereisareflectionofthesubjectivephenomenonandatendencyonthepartofperceptiontoreturnasitweretotheexternalcausewhichhasrousedtilementalstatebecausethelatterisconnectedwiththeformer。"Sergi:PsychologiePhysiologiqueParis，1888，p。189。——TheclearestandbestpassageIknowisinLiebmann:
　　DerObjectiveAnblick1869，pp。67-72，butitisunfortunatelytoolongtoquote。
　　[45]ThisisprovedbyWeber’sdeviceofcausingtheheadtobefirmlypressedagainstasupportbyanotherperson，whereuponthedirectionoftractionceasestobeperceived。
　　[46]Lotze:Med。Psych。，428-433；Lipps:GrundtatsachendesSeelenlebens，582。
　　[47]InjuriestoNervesPhiladelphia，1872，p。350ff。
　　[48]Inrealityitprobablymeansonlyarestlessmovementofdesire，whichhemightmakeevenafterhehadbecomeawareofhisimpotencetotouchtheobject。
　　[49]RevuePhilosophique，vii。p。1ff。，anadmirablecriticalarticle，inthecourseofwhichM。
　　Janetgivesabibliographyofthecasesinquestion。SeealsoDunan:ibid。
　　xxv。165-7。TheyarealsodiscussedandsimilarlyInterpretedbyT。K。
　　Abbot:SightandTouch1864，chapterx。
　　[50]Theintermediaryandshortenedlocationsofthelostbandandfootintheamputationcasesalsoshowthis。Itiseasytoseewhythephantomfootmightcontinuetofollowthepositionoftheartificialone。ButIconfessthatIcannotexplainitshalfway-positions。
　　[51]Itisfromthisconfusedassumptionthatthetime-honoredriddlecomes，ofhow，withanupside-downpictureontheretina，wecanseethingsright-sideup。Ourconsciousnessisnaivelysupposedtoinhabitthepictureandtofeelthepicture’spositionasrelatedtootherobjectsofspace。Butthetruthisthatthepictureisnon-existenteitherasahabitatorasanythingelse，forimmediateconsciousness。Ournotionofitisanenormouslylateconception。Theouterobjectisgivenimmediatelywithallthosequalitieswhichlaterarenamedanddeterminedinrelationtoothersensations。The’bottom’ofthisobjectiswhereweseewhatbytouchweafterwardsknowasourfeet，the’top’istheplaceinwhichweseewhatweknowasotherpeople’sheads，etc。，etc。BerkeleylongagomadethismatterperfectlyclearseehisEssaytowardsanewTheoryofVision，93-98，113-118。
　　[52]Forfulljustificationthereadermustseethenextchapter。Hemayobject，againstthesummaryaccountgivennow，thatinababe’simmediatefieldofvisionthevariousthingswhichappeararelocatedrelativelytoeachotherfromtheoutset。Iadmitthatifdiscriminated，theywouldappearsolocated。
　　Buttheyarepartsofthecontentofonesensation，notsensationsseparatelyexperienced，suchasthetextisconcernedwith。Thefullydeveloped’world，’
　　inwhichalloursensationsultimatelyfindlocation，isnothingbutanimaginaryobjectframedafterthepatternofthefieldofvision，bytheadditionandcontinuationofonesensationuponanotherinanorderlyandsystematicway。IncorroborationofmytextImustrefertopp。57-60ofRiehl’sbookquotedaboveonpage32，andtoUphues:WahrnehmungundEmpfiudung1888，especiallytheEinleitungandpp。51-61。ClassicsintheHistoryofPsychology——James1890Chapter18ThePrinciplesofPsychologyWilliamJames1890CHAPTERXVIII。IMAGINATION。
　　Sensations，onceexperienced，modifythenervousorganism，sothatcopiesofthemariseagaininthemindaftertheoriginaloutwardstimulusisgone。Nomentalcopy，however，canariseinthemind，ofanykindofsensationwhichhasneverbeendirectlyexcitedfromwithout。
　　Theblindmaydreamofsights，thedeafofsounds，foryearsaftertheyhavelosttheirvisionorhearing；[1]
　　butthemanborndeafcanneverbemadetoimaginewhatsoundislike，norcanthemanbornblindeverhaveamentalvision。InLocke’swords，alreadyquoted，"themindcanframeuntoitselfnoonenewsimpleidea。"Theoriginalsofthemallmusthavebeengivenfromwithout。Fantasy，orImagination，arethenamesgiventothefacultyofreproducingcopiesoforiginalsoncefelt。Theimaginationiscalled’reproductive’whenthecopiesareliteral；productive’whenelementsfromdifferentoriginalsarerecombinedsoastomakenewwholes。
　　After-imagesbelongtosensationratherthantoimagination；sothatthemostimmediatephenomenaofimaginationwouldseemtobethosetardierimagesduetowhattheGermanscallSinnesgedä；chtnisswhichwerespokenofinVol。1，p。647，——coercivehauntingsofthemindbyechoesofunusualexperiencesforhoursafterthelatterhavetakenplace。Thephenomenaordinarilyascribedtoimagination，however，arethosementalpicturesofpossiblesensible[p。45]experiences，towhichtheordinaryprocessesofassociativethoughtgiverise。
　　Whenrepresentedwithsurroundingsconcreteenoughtoconstituteadate，thesepictures，whentheyrevive，formrecollection。WehavealreadystudiedthemachineryofrecollectioninChapterXVI。Whenthementalpicturesareofdatafreelycombined，andreproducingnopastcombinationexactly，wehaveactsofimaginationproperlysocalled。OURIMAGESAREUSUALLYVAGUE。
　　Fortheordinary’analytic’psychology，eachsensibly，discernibleelementoftheobjectimaginedisrepresentedbyitsownseparateidea，andthetotalobject，isimaginedbya’cluster’
　　or’gang’ofideas。Wehaveseenabundantreasontorejectthisviewseep。276ff。。Animaginedobject，howevercomplex，isatanyonemomentthoughtinoneidea，whichisawareofallitsqualitiestogether。IfI
　　slipintotheordinarywayoftalking，andspeakofvariousideas’combining，’
　　thereaderwillunderstandthatthisisonlyforpopularityandconvenience，andhewillnotconstrueitintoaconcessiontotheatomistictheoryinpsychology。
　　Humewastheherooftheatomistictheory。
　　Notonlywereideascopiesoforiginalimpressionsmadeonthesense-organs，buttheywere，accordingtohim，completelyadequatecopies，andwereallsoseparatefromeachotherastopossessnomannerofconnection。Humeprovesideasmtheimaginationtobecompletelyadequatecopies，notyappealtoobservation，butbyapriorireasoning，asfollows:
　　"Themindcannotformanynotionofquantityorquality，withoutformingaprecisenotionofthedegreesofeach，"for"’tisconfessedthatnoobjectcanappeartothesenses，orinotherwords，thatnoimpression[2]canbecomepresenttothemind，withoutbeingdeterminedinitsdegreesbothofquantityandquality。Theconfusioninwhichimpressionsaresometimesinvolvedproceedsonlyfromtheirfaintnessandunsteadiness，notfromanycapacityinthemindtoreceiveanyimpression，whichinitsrealexistencehasnoparticulardegreenorproportion。Thatisacontradictioninterms；andevenimpliestheflattest[p。46]ofallcontradictions，viz。，that’tispossibleforthesamethingbothtobeandnottobe。Nowsinceallideasarederivedfromimpressions，andarenothingbutcopiesandrepresentationsofthem，whateveristrueoftheonemustbeacknowledgedconcerningtheother。Impressionsandideasdifferonlyintheirstrengthandvivacity。
　　Theforegoingconclusionisnotfoundedonanyparticulardegreeofvivacity。
　　Itcannotthereforebeaffectedbyanyvariationinthatparticular。Anideaisaweakerimpression；andasastrongimpressionmustnecessarilyhaveadeterminatequantityandquality，thecasemustbethesamewithitscopyorrepresentative。"[3]
　　Theslightestintrospectiveglancewillshowtoanyonethefalsityofthisopinion。Humesurelyhadimagesofhisownworkswithoutseeingdistinctlyeverywordandletteruponthepageswhichfloatedbeforehismind’seye。Hisdictumisthereforeanexquisiteexampleofthewayinwhichamanwillbeblindedbyaprioritheoriestothemostflagrantfacts。Itisaratherremarkablething，too，thatthepsychologistsofHume’sownempiricistschoolhave，asarule，beenmoreguiltyofthisblindnessthantheiropponents。Thefundamentalfactsofconsciousnesshavebeen，onthewhole，moreaccuratelyreportedbythespiritualisticwriters。NoneofHume’spupils，sofarasIknow，untilTaineandHuxley，evertookthepainstocontradicttheopinionoftheirmaster。Prof。HuxleyinhisbrilliantlittleworkonHumesetthematterstraightinthefollowingwords:
　　"Whencompleximpressionsorcomplexideasarereproducedasmemories，itisprobablethatthecopiesnevergiveallthedetailsoftheoriginalswithperfectaccuracy，anditiscertainthattheyrarelydoso。Noonepossessesamemorysogood，thatifhehasonlyonceobservedanaturalobject，asecondinspectiondoesnotshowhimsomethingthathehasforgotten。Almostall，ifnotall，ourmemoriesarethereforesketches，ratherthanportraits，oftheoriginals——thesalientfeaturesareobvious，whilethesubordinatecharactersareobscureorunrepresented。
　　"Now，whenseveralcompleximpressionswhicharemoreorlessdifferentfromoneanother——letussaythatoutoftenimpressionsineach，sixarethesameinall，andfouraredifferentfromalltherest——aresuccessivelypresentedtothemind，itiseasytoseewhatmustbethenatureoftheresult。Therepetitionofthesixsimilarimpressionswillstrengthenthesixcorrespondingelementsofthecomplexidea，[p。47]whichwillthereforeacquiregreatervividness；whilethefourdifferingimpressionsofeachwillnotonlyacquirenogreaterstrengththantheyhadatfirst，but，inaccordancewiththelawofassociation，theywillalltendtoappearatonce，andwillthusneutralizeoneanother。
　　"Thismentaloperationmayberenderedcomprehensiblebyconsideringwhattakesplaceintheformationofcompoundphotographswhentheimagesofthefacesofsixsitters，forexample，areeachreceivedonthesamephotographicplate，forasixthofthetimerequisitetotakeoneportrait。Thefinalresultisthatallthosepointsinwhichthesixfacesagreearebroughtoutstrongly，whileallthoseinwhichtheydifferareleftvague；andthuswhatmaybetermedagenericportraitofthesix，incontradistinctiontoaspecificportraitofanyone，isproduced。
　　"Thusourideasofsinglecompleximpressionsareincompleteinoneway，andthoseofnumerous，moreorlesssimilar，compleximpressionsareincompleteinanotherway；thatistosay，theyaregeneric，notspecific。Andhenceitfollowsthatourideasoftheimpressionsinquestionarenot，inthestrictsenseoftheword，copiesofthoseimpressions；while，atthesametime，theymayexistinthemindindependentlyoflanguage。
　　"Thegenericideaswhichareformedfromseveralsimilar，butnotidentical，complexexperiencesarewhatarecalledabstractorgeneralideas；andBerkeleyendeavoredtoprovethatallgeneralideasarenothingbutparticularideasannexedtoacertainterm，whichgivesthemamoreextensivesignification，andmakesthemrecall，uponoccasion，otherindividualswhicharesimilartothem。Humesaysthatheregardsthisas’oneofthegreatestandthemostvaluablediscoveriesthathasbeenmadeoflateyearsintherepublicofletters，’andendeavorstoconfirmitinsuchamannerthatitshallbe’putbeyondalldoubtandcontroversy。’
　　"Imayventuretoexpressadoubtwhetherhehassucceededinhisobject；butthesubjectisanabstruseone；andImustcontentmyselfwiththeremark，thatthoughBerkeley’sviewappearstobelargelyapplicabletosuchgeneralideasasareformedafterlanguagehasbeenacquired，andtoallthemoreabstractsortofconceptions，yetthatgeneralideasofsensibleobjectsmayneverthelessbeproducedinthewayindicated，andmayexistindependentlyoflanguage。Indreams，oneseeshouses，trees，andotherobjects，whichareperfectlyrecognizableassuch，butwhichremindoneoftheactualobjectsasseenIoutofthecorneroftheeye，orofthepicturesthrownbyabadly-focussedmagiclantern。Amanaddressesuswhoislikeafigureseenintwilight，orwetravelthroughcountrieswhereeveryfeatureofthesceneryisvague；theoutlinesofthehillsareill-marked，andtherivershavenodefinedbanks。
　　Theyare，inshort，genericideasofmanypastimpressionsofmen，hills，andrivers。Ananatomistwhooccupieshimselfintentlywiththeexaminationofseveralspecimensofsomenewkindofanimal，incourseoftimeacquiressovividaconceptionofitsformandstruc-[p。48]turethattheideamaytakevisibleshapeandbecomeasortofwakingdream。Butthefigurewhichthuspresentsitselfisgeneric，notspecific。Itisnocopyofanyonespecimen，but，moreorless，ameanoftheseries；andthereseemsnoreasontodoubtthatthemindsofchildrenbeforetheylearntospeak，andofdeaf-mutes，arepeopledwithsimilarlygeneratedgenericideasofsensibleobjects。"[4]AreVagueImages’AbstractIdeas’？
　　TheonlypointwhichIamtemptedtocriticiseinthisaccountisProf。Huxley’sidentificationofthesegenericimageswith’abstractorgeneralideas’inthesenseofuniversalconceptions。
　　Tainegivesthetruerview。Hewrites:
　　"SomeyearsagoIsawinEngland，inKewGardens，forthefirsttime，araucarias，andIwalkedalongthebedslookingatthesestrangeplants，withtheirrigidbarkandcompact，short，scalyleaves，ofasombregreen，whoseabrupt，rough，bristlingformcutinuponthefinesoftly-lightedturfofthefreshgrass-plat。IfInowinquirewhatthis，experiencehasleftinme，Ifind，first，thesensiblerepresentationofanaraucaria；infact，Ihavebeenabletodescribealmostexactlytheformandcoloroftheplant。Butthereisadifferencebetweenthisrepresentationandtheformersensations，ofwhichitisthepresentecho。Theinternalsemblance，fromwhichIhavejustmademydescription，isvague，andmypastsensationswereprecise。For，assuredly，eachofthearaucariasI
　　sawthenexcitedinmeadistinctvisualsensation；therearenotwoabsolutelysimilarplantsinnature；Iobservedperhapstwentyorthirtyaraucarias；
　　withoutadoubteachoneofthemdifferedfromtheothersinsize，ingirth，bythemoreorlessobtuseanglesofitsbranches，bythemoreorlessabruptjuttingoutofitsscales，bythestyleofitstexture；consequently，mytwentyorthirtyvisualsensationsweredifferent。Butnooneofthesesensationshascompletelysurvivedinitsecho；thetwentyorthirtyrevivalshavebluntedoneanother；thusupsetandagglutinatedbytheirresemblancetheyareconfoundedtogether，andmypresentrepresentationistheirresidueonly。Thisistheproduct，orratherthefragment，whichisdepositedinus，whenevehavegonethroughaseriesofsimilarfactsorindividuals，Ofournumerousexperiencesthereremainonthefollowingdayfourorfivemoreorlessdistinctrecollections，which，obliteratedthemselves，leavesbehindinusasimplecolorless，vaguerepresentation，intowhichenterascomponentsvariousrevivingsensations，inanutterlyfeeble，incomplete，andabortivestate——Butthisrepresentationisnotthegeneralandabstractidea。Itisbutitsaccompaniment，and，ifImaysayso，theorefromwhichitisextracted。Fortherepresentation，thoughbadly，sketched，isasketch，thesensiblesketchofadistinctindividual。
　　Butmyabstractideacorrespondstothewholeclass；itdiffers，thenfromtherepresentationofinindividual——
　　Moreover，myabstractidea[p。49]isperfectlyclearanddeterminate；
　　nowthatIpossessit，Ineverfalltorecognizeanaraucariaamongthevariousplantswhichmaybeshownme；itdiffersthenfromthecoilusedandfloatingrepresentationIhaveofsomeparticulararaucaria。"[5]
　　Inotherwords，ablurredpictureisjustasmuchasinglementalfactasasharppictureis；andtheuseofeitherpicturebythemindtosymbolizeawholeclassofindividualsisanewmentalfunction，requiringsomeothermodificationofconsciousnessthanthemereperceptionthatthepictureisdistinctornot。Imaybewailtheindistinctnessofmymentalimageofmyabsentfriend。Thatdoesnotpreventmythoughtfrommeaninghimalone，however。AndImaymeanallmankind，withperhapsaverysharpimageofonemaninmymind’seye。ThemeaningisafunctionofthemoreItransitive’partsofconsciousness，the’fringe’ofrelationswhichwefeelsurroundingtheimage，bethelattersharpordim。Thiswasexplainedinapreviousplaceseep。473ff。，especiallythenotetopage477，andIwouldnottouchuponthematteratallherebutforitshistoricalinterest。
　　Ourideasorimagesofpastsensibleexperiencesmaythenbeeitherdistinctandadequateordim，blurred，andincomplete。
　　ItislikelythatthedifferentdegreesinwhichdifferentmenareabletomakethemsharpandcompletehashadsomethingtodowithkeepingupsuchphilosophicdisputesasthatofBerkeleywithLockeoverabstractideas。Lockehadspokenofourpossessing’thegeneralideaofatriangle’
　　which"mustbeneitherobliquenorrectangle，neitherequilateral，equicrural，norscalenon，butallandnoneoftheseatonce。"Berkeleysays:
　　"Ifanymanhasthefacultyofframinginhismindsuchanideaofatriangleasisheredescribed，itisinvaintopretendtodisputehimoutofit，norwouldIgoaboutit。AllIdesireisthatthereaderwouldfullyandcertainlyinformhimselfwhetherhehassuchanideaorno。"[6]
　　Untilveryrecentyearsitwassupposedbyallphilosophersthattherewasatypicalhumanmindwhichallindividualmindswerelike，andthatpropositionsofuniversalvaliditycouldbelaiddownaboutsuchfacultiesas’the[p。50]Imagination。’Lately，however，amassofrevelationshavepouredin，whichmakeusseehowfalseaviewthisis。Thereareimaginations，not’TheImagination，’andtheymustbestudiedindetail。INDIVIDUALSDIFFERINIMAGINATION。
　　ThefirstbreakerofgroundinthisdirectionwasFechner，in1860。Fecherwasgiftedwithunusualtalentforsubjectiveobservation，andinchapterxivofhis’Psychophysik’hegavetheresultsofamostcarefulcomparisonofhisownopticalafter-images，withhisopticalmemory-pictures，togetherwithaccountsbyseveralotherindividualsoftheiropticalmemory-pictures。[7]Theresultswastoshowagreat[p。
　　51]personaldiversity。"Itwouldbeinteresting，"hewrites，toworkupthesubjectstatistically；andIregretthatotheroccupationshavekeptmefromfulfillingmyearlierintentiontoproceedinthisway。"
　　Fechner’sintentionwasindependentlyexecutedbyMr。Galton，thepublicationofwhoseresultsin1880maybesaidtohavemadeaneraindescriptivePsychology。
　　"Itisnotnecessary，"saysGalton，"totroublethereaderwithmyearlytentativesteps。Aftertheinquiryhadbeenfairlystartedittooktheformofsubmittingacertainnumberofprintedquestionstoalargenumberofpersons。Thereishardlyanymoredifficulttaskthanthatofframingquestionswhicharenotlikelytobemisunderstood，whichadmitofeasyreply，andwhichcoverthegroundofinquiry。Ididmybestintheserespects，withoutforgettingthemostimportantpartofall-namely，totemptmycorrespondentstowritefreelyinfullerexplanationoftheirreplies，andoncognatetopicsaswell。Theseseparatelettershaveprovedmoreinstructiveandinterestingbyfarthantherepliestothesetquestions。
　　"Thefirstgroupoftheratherlongseriesofqueriesrelatedtotheillumination，definition，andcoloringofthementalimage，andwereframedthus:
　　"BeforeaddressingyourselftoanyoftheQuestionsontheoppositepage，thinkofsomedefiniteobject——supposeitisyourbreakfast-tableasyousatdowntoitthismorning——andconsidercarefullythepicturethatrisesbeforeyourmind’seye。
　　"’1。Illumination——Istheimagedimorfairlyclear？Isitsbrightnesscomparabletothatoftheactualscene？
　　"’2。Definition——Arealltheobjectsprettywelldefinedatthesametimid，oristheplaceofsharpestdefinitionatanyonemomentmorecontractedthanitisinarealscene？
　　"’3。Coloring-Arethecolorsofthechina，ofthetoast，bread-crust，mustard，meat，parsley，orwhatevermayhavebeenonthetable，quitedistinctandnatural？’
　　"Theearliestresultsofmyinquiryamazedme。Ihadbegunbyquestioningfriendsinthescientificworld，astheywerethemostlikelyclassofmentogiveaccurateanswersconcerningthisfacultyofvisual-[p。52]izing，towhichnovelistsandpoetscontinuallyallude，whichhasleftanabidingmarkonthevocabulariesofeverylanguage，andwhichsuppliesthematerialoutofwhichdreamsandthewell-knownhallucinationsofsickpeoplearebuilt。
　　"Tomyastonishment，Ifoundthat，thegreatmajorityofthemenofsciencetowhomIfirstappliedprotestedthatmentalimagerywayunknowntothem，andtheylookedonmeasfancifulandfantasticinsupposingthatthewords’mentalimagery’reallyexpressedwhatIbelievedeverybodysupposedthemtomean。Theyhadnomorenotionofitstruenaturethanacolor-blindman，whohasnotdiscernedhisdefect，hasofthenatureofcolor。Theyhadamentaldeficiencyofwhichtheywereunaware，andnaturallyenoughsupposedthatthosewhoaffirmedtheypossesseditwereromancing。Toillustratetheirmentalattitudeitwillbesufficienttoquoteafewlinesfromtheletterofoneofmycorrespondents，whowrites:
　　"Thesequestionspresupposeassenttosomesortofapropositionregardingthe"mind’seye，"andthe"images"whichitsees……Thispointstosomeinitialfallacy……ItisonlybyafigureofspeechthatIcandescribemyrecollectionofasceneasa"mentalimage"whichIcan"see"withmy"mind’seye。"……Idonotseeit……anymorethanamanseesthethousandlinesofSophocleswhichunderduepressureheisreadytorepeat。Thememorypossessesit，’etc。
　　"MuchthesameresultfollowedinquiriesmadeformebyafriendamongmembersoftheFrenchInstitute。
　　"Ontheotherhand，whenIspoketopersonswhomImetingeneralsociety，Ifoundanentirelydifferentdispositiontoprevail。Manymenandayetlargenumberofwomen，andmanyboysandgirls，declaredthattheyhabituallysawmentalimagery，andthatitwayperfectlydistincttothemandfullofcolor。ThemoreIpressedandcrossed-questionedthem，professingmyselftobeincredulous，themoreobviouswasthetruthoftheirfirstassertions。Theydescribedtheirimageryinminutedetail，andtheyspokeinatoneofsurpriseatmyapparenthesitationinacceptingwhattheysaid。IfeltthatImyselfshouldhavespokenexactlyastheydidifIhadbeendescribingascenethatlaybeforemyeyes，inbroaddaylight，toablindmanwhopersistedindoubtingtherealityofvision。Reassuredbythishappierexperience，Irecommencedtoinquireamong"scientificmen，andsoonfoundscatteredinstancesofwhatIsought，thoughinbynomeansthesameabundanceaselsewhere。Ithencirculatedmyquestionsmoregenerallyamongmyfriendsandthroughtheirhands，andobtainedreplies……frompersonsofbothsexes，andofvariousages，andintheendfromoccasionalcorrespondentsinnearlyeverycivilizedcountry。
　　"IhavealsoreceivedbatchesofanswersfromvariouseducationalestablishmentsbothinEnglandandAmerica，whichweremadeafterthemastershadfullyexplainedthemeaningofthequestions，andinterestedtheboysinthem。Thesehavethemeritofreturnsderivedfromageneralcensus，whichmyotherdatalack，becauseIcannotfor[p。
　　53]amomentsupposethatthewritersofthelatterareahaphazardproportionofthosetowhomtheyweresent。IndeedIknowofsomewho，disavowingallpossessionofthepower，andofmanyotherswho，possessingitintoofaintadegreetoenablethemtoexpresswhattheirexperiencesreallywere，inamannersatisfactorytothemselves，sentnoreturnsatall。Considerablestatisticalsimilaritywas，however，observedbetweenthesetsofreturnsfurnishedbytheschoolboysandthosesentbymyseparatecorrespondents，andImayaddthattheyaccordinthisrespectwiththeoralinformationIhaveelsewhereobtained。Theconformityofrepliesfromsomanydifferentsourceswhichwasclearfromthefirst，thefactoftheirapparenttrustworthinessbeingonthewholemuchincreasedbycross-examinationthoughIcouldgiveoneortwoamusinginstancesofbreak-down，andtheevidenteffortmadetogiveaccurateanswers，haveconvincedmethatitisamucheasiermatterthanIhadanticipatedtoobtaintrustworthyrepliestopsychologicalquestions。Manypersons，especiallywomenandintelligentchildren，takepleasureinintrospection，andstrivetheirverybesttoexplaintheirmentalprocesses。Ithinkthatadelightinself-dissectionmustbeastrongingredientinthepleasurethatmanyaresaidtotakeinconfessingthemselvestopriests。
　　"Here，then，aretworathernotableresults:
　　theoneistheprovedfacilityofobtainingstatisticalinsightintotheprocessesofotherpersons’minds，whateveraprioriobjectionmayhavebeenmadeastoitspossibility；andtheotheristhatscientificmen，asaclass，havefeeblepowersofvisualrepresentation。Thereisnodoubtwhateveronthelatterpoint，howeveritmaybeaccountedfor。Myownconclusionisthatanover-readyperceptionofsharpmentalpicturesisantagonistictotheacquirementofhabitsofhighly-generalizedandabstractthought，especiallywhenthestepsofreasoningarecarriedonbywordsassymbols，andthatifthefacultyofseeingthepictureswaseverpossessedbymenwhothinkhard，itisveryapttobelostbydisuse。Thehighestmindsareprobablythoseinwhichitisnotlost，butsubordinated，andisreadyforuseonsuitableoccasions。Iam，however，boundtosaythatthemissingfacultyseemstobereplacedsoserviceablybyothermodesofconception，chiefly，Ibelieve，connectedwiththeincipientmotorsense，notoftheeyeballsonlybutofthemusclesgenerally，thatmenwhodeclarethemselvesentirelydeficientinthepowerofseeingmentalpicturescanneverthelessgivelifelikedescriptionsofwhattheyhaveseen，andcanotherwiseexpressthemselvesasiftheyweregiftedwithavividvisualimagination。
　　TheycanalsobecomepaintersofrankofRoyalAcademicians。[8]……[p。54]
　　"Itisamistaketosupposethatsharpsightisaccompaniedbyclearvisualmemory。Ihavenotafewinstancesinwhichtheindependenceofthetwofacultiesisemphaticallycommentedon；andIhaveatleastoneclearcasewheregreatinterestinoutlinesandaccurateappreciationofstraightness，squareness，andthelike，isunaccompaniedbythepowerofvisualizing。Neitherdoesthefacultygowithdreaming。Ihavecaseswhereitispowerful，andatthesametimewheredreamsarerareandfaintoraltogetherabsent。Onefriendtellsmethathisdreamshavenotthehundredthpartofthevigorofhiswakingfancies。
　　"Thevisualizingandtheidentifyingpowersarebynomeansnecessarilycombined。Adistinguishedwriteronmetaphysicaltopicsassuresmethatheisexceptionallyquickatrecognizingafacethathehasseenbefore，butthathecannotcallupamentalimageofanyfacewithclearness。
　　"Somepersonshavethepowerofcombininginasingleperceptionmorethancanbeseenatanyonemomentbythetwoeyes……
　　"Ifindthatafewpersonscan，bywhattheyoftendescribeasakindoftouch-sight，visualizeatthesamemomentallroundtheimageofasolidbody。Manycandosonearly，butnotaltogetherroundthatofaterrestrialglobe。Aneminentmineralogistassuresmethatheisabletoimaginesimultaneouslyallthesidesofacrystalwithwhichheisfamiliar。Imaybeallowedtoquoteacuriousfacultyofmyowninrespecttothis。Itisexercisedonlyoccasionallyandindreams，orratherinnightmares，butunderthosecircumstancesIamperfectlyconsciousofembracinganentiresphereinasingleperception。Itappearstoliewithinmymentaleyeball，andtobeviewedcentripetally。
　　"Thispowerofcomprehensionispracticallyattainedinmanycasesbyindirectmethods。Itisacommonfeattotakeinthewholesurroundingsofanimaginedroomwithsucharapidmentalsweepastoleavesomedoubtwhetherithasnotbeenviewedsimultaneously。
　　Somepersonshavethehabitofviewingobjectsasthoughtheywerepartlytransparent；thus，iftheysodisposeaglobeintheirimaginationastoseebothitsnorthandsouthpolesatthesametime，theywillnotbeabletoseeitsequatorialparts。Theycanalsoperceivealltheroomsofanimaginaryhousebyasinglementalglance，thewallsandfloorsbeingasifmadeofglass。Afourthclassofpersonshavethehabitofrecallingscenes，notfromthepointofviewwhencetheywereobserved，butfromadistance，andtheyvisualizetheirownselvesasactorsonthementalstage。Byoneorotheroftheseways，thepowerofseeingthewholeofanobject，andnotmerelyoneaspectofit，ispossessedbymanypersons。
　　"Theplacewheretheimageappearstoliediffersmuch。Mostpersonsseeitinanindefinablesortofway，othersseeitinfrontoftheeye，othersatadistancecorrespondingtoreality。
　　Thereexistsapowerwhichisrarenaturally，butcan，Ibelieve，beacquiredwithoutmuchdifficulty，ofprojectingamentalpictureuponapieceofpaper，andof[p。55]holdingitfastthere，sothatitcanbeoutlinedwithapencil。TothisIshallrecur。
　　"Imagesusuallydonotbecomestrongerbydwellingonthem；thefirstideaiscommonlythemostvigorous，butthisisnotalwaysthecase。Sometimesthementalviewofalocalityisinseparablyconnectedwiththesenseofitspositionasregardsthepointsofthecompass，realorimaginary。Ihavereceivedfullandcuriousdescriptionsfromverydifferentsourcesofthisstronggeographicaltendency，andinoneortwocasesIhavereasontothinkitalliedtoaconsiderablefacultyofgeographicalcomprehension。
　　"Thepowerofvisualizingishigherinthefemalesexthaninthemale，andissomewhat，butnotmuch，higherinpublic-schoolboysthaninmen。Aftermaturityisreached，thefurtheradvanceofagedoesnotseemtodimthefaculty，butratherthereverse，judgingfromnumerousstatementstothateffect；butadvancingyearsaresometimesaccompaniedbyagrowinghabitofhardabstractthinking，andinthesecasesnotuncommonamongthosewhomIhavequestioned——thefacultyundoubtedlybecomesimpaired。Thereisreasontobelievethatitisveryhighinsomeyoungchildren，whoseemtospendyearsofdifficultyindistinguishingbetweenthesubjectiveandobjectiveworld。Languageandbook-learningcertainlytendtodullit。