e；and　this　is　Intelligence。　〃The　basis　of　instinct　is　heredity　and　we　can　impute　an　action　to　pure　instinct　only　if　it　is　hereditary。　The　other　class　of　actions　are　those　devised　by　the　individual　animal　for　himself　on　the　basis　of　his　own　experience　and　these　are　called　generally　intelligent。　Of　intelligence　operating　within　the　sphere　of　instinct　there　is　ample　evidence。　There　are　modifications　of　instinctive　action　directly　traceable　to　experience　which　cannot　be　explained　by　the　interaction　of　purely　hereditary　tendencies　and　there　are　cases　in　which　the　whole　structure　of　the　instinct　is　profoundly　modified　by　the　experience　of　the　individual。〃　Hobhouse；　whom　I　quote；　goes　on　to　give　many　examples　of　instinctive　action　modified　by　experience　and　intelligence　in　the　insect　and　lower　animal　world。　What　I　wish　especially　to　point　out　is　that　man　has　many　instinctive　bases　for　conduct；　but　instincts　as　such　are　not　often　seen　in　pure　form　in　man。　They　are　constantly　modified　by　other　instincts　and　through　them　runs　the　influence　of　intelligence。　The　function　of　intelligence　is　to　control　instincts；　to　choose　ways　and　means　for　the　fulfillment　of　instincts　that　are　blocked；　etc。　Moreover；　the　effects　of　teachings；　ethics；　social　organization　and　tradition；　operating　through　the　social　instincts；　are　to　repress；　inhibit　and　whip　into　conformity　every　mode　of　instinctive　conduct。　The　main　instincts　are　those　relating　to　nutrition　and　reproduction；　the　care　of　the　young；　to　averting　danger　or　destroying　it；　to　play　and　organized　activity；　to　acquiring；　perhaps　to　teaching　and　learning　and　to　the　social　relations　generally。　But　manners　creep　in　to　regulate　our　methods　of　eating　and　the　things　we　shall　eat；　and　we　may　not　eat　at　all　unless　we　agree　to　get　the　things　to　eat　a　certain　way。　We　may　not　cohabit　except　under　tremendous　restriction；　and　marriage　with　its　aims　and　purposes　is　sexual　in　origin　but　modified　largely　and　almost　beyond　recognition　by　social　consideration；　taste；　esthetic　matters；　taboos　and　economic　conditions。　We　may　not　treat　our　enemy　as　instinct　bids　us　do；for　only　in　war　may　one　kill　and　here　one　kills　without　any　personal　purpose　or　anger；　almost　without　instinct。　We　may　be　compelled　through　social　exigencies　to　treat　our　enemy　politely；　eat　with　him；　sleep　with　him　and　help　him　out　of　difficulties　and　thus　completely　thwart　one　instinctive　set　of　reactions。　Play　becomes　regulated　by　rules　and　customs；　becomes　motivated　by　the　desire　for　superiority；　or　the　desire　for　gain；　and　may　even　leave　the　physical　field　entirely　and　become　purely　mental。　And　so　on。　It　does　no　special　practical　good　to　discuss　instincts　as　if　they　operated　in　man　as　such。　They　become　purposes。　Therefore　we　shall　defer　the　consideration　of　instincts　and　purposes　in　detail　until　later　chapters　of　this　book。　Since　instincts　are　too　rigid　to　meet　the　needs　of　the　social　and　traditional　life　of　man；　they　become　intellectualized　and　socialized　into　purposes　and　ambitions；　sometimes　almost　beyond　recognition。　Nevertheless；　the　driving　force　of　instinct　is　behind　every　purpose；　every　ambition；　even　though　the　individual　himself　has　not　the　slightest　idea　of　the　force　that　is　at　work。　This　does　not　mean　that　instinct　acts　as　a　sort　of　cellar…　plotter；　roving　around　in　a　subconsciousness；　or　at　least　no　such　semi…diabolical　personality　need　be　postulated；　any　more　than　it　need　be　postulated　for　the　automatic　mechanism　that　regulates　heartbeat　or　digestion。　The　organic　tensions　and　depressions　that　constitute　instinct　are　not　conscious　or　subconscious；　they　affect　our　conscious　personalities　so　that　we　desire　something；　we　fit　that　desire　in　with　the　rest　of　our　desires；　we　seek　the　means　of　gratifying　that　desire　first　in　accordance　with　means　that　Nature　has　given　us　and　second　in　accordance　with　social　teaching　and　our　intelligence。　If　the　desire　brings　us　sharply　in　contact　with　obstacles　imposed　either　by　circumstances　or　more　precious　desire；　we　inhibit　that　desire；and　thus　the　instinct。　Because　organic　tensions　and　depressions　are　periodic　and　are　dependent　upon　the　activities　of　glands　and　tissues　not　within　our　control；　the　desires　may　never　be　completely　squelched　and　may　arise　as　often　as　some　outer　stimulus　brings　them　into　activity；　to　plague　and　disorder　the　life　of　the　conscious　personality。　3。　With　this　preliminary　consideration　of　instinct；　we　pass　on　to　certain　of　the　phases　of　intelligence。　How　to　define　intelligence　is　a　difficulty　best　met　by　ignoring　definition。　But　this　much　is　true：　that　the　prime　function　of　intelligence　is　to　store　up　the　past　and　present　experiences　so　that　they　can　be　used　in　the　future；　and　that　it　adds　to　the　rigid　mechanism　of　instinct　a　plastic　force　which　by　inhibiting　and　exciting　activity　according　to　need　steers　the　organism　through　intricate　channels。　Instinct；　guided　by　a　plan；　conveniently　called　Nature's　plan；　is　not　itself　a　planner。　The　discharge　of　one　mechanism　discharges　another　and　so　on　through　a　series　until　an　end　is　reached；an　end　apparently　not　foreseen　by　the　organism　but　acting　for　the　good　of　the　race　to　which　the　organism　belongs。　Intelligence；　often　enough　not　conscious　of　the　plans　of　Nature；＇1＇　indeed；　decidedly　ignorant　of　these　plans；　works　for　some　good　established　by　itself　out　of　stimuli　set　up　by　the　instincts。　It　plans；　looks　backward　and　forward；　reaches　the　height　of　reflecting　on　itself；　gets　to　recognize　the　existence　of　instinct　and　sets　itself　the　task　of　controlling　instinct。　Often　enough　it　fails；　instinct　breaks　through；　takes　possession　of　the　means　of　achievement；　accomplishes　its　purposebut　the　failure　of　intelligence　to　control　and　the　misguided　control　it　attempts　and　assumes　are　merely　part　of　the　general　imperfections　of　the　organism。　A　perfect　intelligence　would　be　clearly　able　to　understand　its　instincts；　to　give　each　of　them　satisfaction　by　a　perfect　compromise；　would　pick　the　methods　for　accomplishment　without　error；　and　storing　up　the　past　experiences　without　loss；　would　meet　the　future　according　to　a　plan。
  ＇1＇　We　are　at　this　stage　in　a　very　dark　place　in　human　thought。　We　say　that　instincts　seek　the　good　of　the　race；　or　have　some　racial　purpose；　as　the　sexual　instinct　has　procreation　as　its　end。　But　the　lover　wooing　his　sweetheart　has　no　procreation　plan　in　his　mind；　he　is　urged　on　by　a　desire　to　win　this　particular　girl；　a　desire　which　is　in　part　sexual；　in　part　admiration　of　her　beauty；　grace；　and　charm；　again　it　is　the　pride　of　possession　and　achievement；　and　further　is　the　result　of　the　social　and　romantic　ideals　taught　in　books；　theaters；　etc。　He　may　not　have　the　slightest　desire　for　a　child；　as　individual　he　plans　one　thing；but　we　who　watch　him　see　in　his　approach　the　racial　urge　for　procreation　and　even　disregard　his　purposes　as　unimportant。　Who　and　what　is　the　Race；　where　does　it　reside；　how　can　it　have　purposes？　Call　it　Nature；　and　we　are　no　better　off。　We　must　fall　back　on　an　ancient　personalization　of　forces；　and　our　minds　rest　easier　when　we　think　of　a　Planner　operating　in　all　of　us　and　perhaps　smiling　as　He　witnesses　our　strivings。
  As　we　study　the　nervous　systems　of　animals；　we　find　that　with　the　apparent　growth　of　intelligence　there　is　a　development　of　that　part　of　the　brain　called　the　cerebrum。　In　so　far　as　certain　other　parts　of　the　brain　are　concernedmedulla；　pons；　mid…brain；　basal　ganglia　cerebellumwe　who　are　human　are　not　essentially　superior　to　the　dog；　the　cow；　the　elephant　or　the　monkey。　But　when　the　neopallium；　or　the　cerebrum；　is　considered；　the　enormous　superiority　of　man　（and　the　superiority　of　the　higher　over　the　lower　animals）　becomes　striking。　Anatomically　the　cerebrum　is　a　complex　elaboration　of　cells　and　fibers　that　have　these　main　purposes：　First；　to　record　in　perfect　and　detailed　fashion　the　EXPERIENCES　of　the　organism；　so　that　here　are　memory　centers　for　visual　and　auditory　experiences；　for　skin；　joint　and　bone　experiences　of　all　kinds；　speech　memories；　action　memories；　and　undoubtedly　for　the　recording　in　some　way　not　understood　of　the　pleasure…pain　feelings。　Second；　it　has　a　hold；　a　grip　on　the　motor　mechanism　of　the　body；　on　the　muscles　that　produce　action；　so　that　the　intelligence　can　nicely　adapt　movement　to　the　circumstances；　to　purpose；　and　can　inhibit　the　movements　that　arise　reflexly。　Thus　in　certain　diseases；　where　the　part　of　the　brain　involved　in　movement　is　injured；　voluntary　movement　disappears　but　reflex　action　is　increased。　Third；　the　neopallium；　or　cerebrum；　is　characterized　by　what　are　known　as　association　tracts；　i。e。；　connections　of　intricate　kinds　which　link　together　areas　of　the　brain　having　different　functions　and　thus　allow　for　combinations　of　activity　of　all　kinds。　The　brain　thus　acts　to　increase　the　memories　of　the　past；　and；　as　we　all　know；　man　is　probably　the　only　animal　to　whom　the　past　is　a　controlling　force；　sometimes　even　an　overpowering　force。　It　acts　to　control　the　conduct　of　the　individual；　to　delay　or　to　inhibit　it；　and　it　acts　to　increase　in　an　astonishing　manner　the　number　of　reactions　possible。　One　stimulus　arousing　cerebral　excitement　may　set　going　mechanisms　of　the　brain　through　associated　tracts　that　will　produce　conduct　of　one　kind　or　another　for　years　to　come。　We　spoke