Surveyingthesubject，then，fromthisego—altruisticposition，wecanperceivewhymatrimony，aswepractiseit，shouldresultinincreasingthepersonalityofourrace：forthereasonnamelythatpsychicalsimilaritydeterminestheselection。Atfirstsight，indeed，suchanaturalaffinitywouldseemtohavelittleornothingtodowithmarriage。Asfarasoutsidersarecapableofjudging，unlikesappeartofancyoneanotherquiteasgratuitouslyasdolikes。Connubialcouplesareoftenanythingbuttwinsouls。Yetourowndualuseoftheword\"like\"bearshistoricwitnesstothecontrary。ForinthisexpressionwehavearecordfromearlyGothictimesthatmenlikedothersforbeinglikethemselves。Sincethen，ourfeelingshavenotchangedmaterially，althoughourmodeofshowingthemisslightlylessintense。Inthosesimpledaysstrangerandenemyweresynonymousterms，andtheirobjectswerereceivedinacorrespondingspirit。Inourpresentrefinedcivilizationwehurlepithetsinsteadofspears，andcontentourselveswithbrandingasheterodoxtheopinionsofanotherwhichdonothappentocoincidewithourown。Theinstinctofself—developmentnaturallybegetsthisself—sidedview。Weinsensiblyfindthosepersonscongenialwhoseideasresembleours，andgravitatetothem，asleavesonaponddotooneanother，nearerandnearertilltheytouch。Isitlikely，then，thatinthemostimportantcaseofalltheruleshouldsuddenlyceasetohold？IsittobepresumedthatevenSocrateschoseXantippeforherremarkablecontrarietytohimself？
Merephysicalattractionisanothermatter。Corporeallyconsidered，mennotinfrequentlyfallinlovewiththeiropposites，thephenomenallytallwiththepainfullyshort，theunnecessarilystoutwiththedistressinglyslender。Butevensuchinartisticjuxtapositionsaremuchlesscommonthanweareaptattimestothink。Foritmustneverbeforgottenthattheexceptionalcharacterofthephenomenarendersthemconspicuous，thecustomarymoreconsortedcombinationsfailingtoexciteattention。
Besides，thereexistsareasonforphysicalincongruitywhichdoesnotholdpsychically。Naturesanctionstheonewhileshediscountenancestheother。Insteadoftheforethoughtsheoncebestoweduponthebody，itreceivesatherhandsnowbutthescantiestattention。Itsdevelopmenthasceasedtobeanobjectwithher。Forsometimepastalmostallhercarehasbeendevotedtotheevolutionofthesoul。Theconsequenceisthatphysicallymanismuchlessspecializedthanmanyotheranimals。Inotherwords，heisbodilylessadvancedintheraceforcompetitiveextermination。Hebelongstoanantiquated，inefficienttypeofmammal。Hisorganismisstillofthejack—of—all—tradespattern，suchasprevailedgenerallyinthemoreyouthfulstagesoforganiclife——onenotspeciallysuitedtoanyparticularpursuit。Wereitnotforhiscerebralconvolutionshecouldnotcompeteforaninstantinthestruggleforexistence，andeventhemonkeywouldreigninhisstead。Butbrainismoreeffectivethanbiceps，andabeingwhocankillhisopponentfartheroffthanhecanseehimevidentlyneedsnogreatexcellenceofbodytosurvivehisfoe。
Thefieldofcompetitionhasthusbeentransferredfrommattertomind，butthefighthaslostnoneofitskeennessinconsequence。
Withthesamezealwithwhichadvantageousanatomicalvariationswereseizeduponandperpetuated，psychicalonesarenowgraspedandrenderedhereditary。Nowifoppositesweretofancyandwedoneanother，suchfortunateimprovementswouldsoonbelost。Theywouldbescatteredoverthecommunityatlargeevenittheyescapedentireneutralization。Topreventsodisastrousaresultnatureimplantsadesireforresemblance，whichdesiremaninstinctivelyactsupon。