ing　metaphysics　as　the　plague。　It　does　not　define　character　or　seek　to　separate　it　from　mind　and　personality。　Written　by　a　neurologist；　a　physician　in　the　active　practice　of　his　profession；　it　cannot　fail　to　bear　more　of　the　imprint　of　medicine；　of　neurology；　than　of　psychology　and　philosophy。　Yet　it　has　also　laid　under　contribution　these　fields　of　human　effort。　Mainly　it　will；　I　hope；　bear　the　marks　of　everyday　experience；　of　contact　with　the　world　and　with　men　and　women　and　children　as　brother；　husband；　father；　son；　lover；　hater；　citizen；　doer　and　observer。　For　it　is　this　plurality　of　contact　that　vitalizes；　and　he　who　has　not　drawn　his　universals　of　character　out　of　the　particulars　of　everyday　life　is　a　cloistered　theorist；　aloof　from　reality。
  CHAPTER　I。　THE　ORGANIC　BASIS　OF　CHARACTER　The　history　of　Man's　thought　is　the　real　history　of　mankind。　Back　of　all　the　events　of　history　are　the　curious　systems　of　beliefs　for　which　men　have　lived　and　died。　Struggling　to　understand　himself；　Man　has　built　up　and　discarded　superstitions；　theologies　and　sciences。　Early　in　this　strange　and　fascinating　history　he　divided　himself　into　two　partsa　body　and　a　mind。　Working　together　with　body；　mind　somehow　was　of　different　stuff　and　origin　than　body　and　had　only　a　mysterious　connection　with　it。　Theology　supported　this　belief；　metaphysics　and　philosophy　debated　it　with　an　acumen　that　was　practically　sterile　of　usefulness。　Mind　and　body　〃interacted〃　in　some　mysterious　way；　mind　and　body　were　〃parallel〃　and　so　set　that　thought…processes　and　brain…processes　ran　side　by　side　without　really　having　anything　to　do　with　one　another。＇1＇　With　the　development　of　modern　anatomy；　physiology　and　psychology；　the　time　is　ripe　for　men　boldly　to　say　that　applying　the　principle　of　causation　in　a　practical　manner　leaves　no　doubt　that　mind　and　character　are　organic；　are　functions　of　the　organism　and　do　not　exist　independently　of　it。　I　emphasize　〃practical〃　in　relation　to　causation　because　it　would　be　idle　for　us　here　to　enter　into　the　philosophy　of　cause　and　effect。　Such　discussion　is　not　taken　seriously　by　the　very　philosophers　who　most　earnestly　enter　into　it。　＇1＇　William　James　in　Volume　1　of　his　〃Psychology〃　gives　an　interesting　resume　of　the　theories　that　consider　the　relationship　of　mind　（thought　and　consciousness）　to　body。　He　quotes　the　〃lucky〃　paragraph　from　Tyndall；　〃The　passage　from　the　physics　of　the　brain　to　the　corresponding　facts　of　consciousness　is　unthinkable。　Granted　that　a　definite　thought　and　a　definite　molecular　action　in　the　brain　occur　simultaneously；　we　do　not　possess　the　intellectual　organ；　or　apparently　any　trace　of　the　organ　which　would　enable　us　to　pass　by　a　process　of　reasoning　from　one　to　the　other。〃　This　is　the　〃parallel〃　theory　which　postulates　a　hideous　waste　of　energy　in　the　universe　and　which　throws　out　of　count　the　same　kind　of　reasoning　by　which　Tyndall　worked　on　light；　heat；　etc。　We　cannot　understand　the　beginning　and　the　end　of　motion；　we　cannot　understand　causation。　Probably　when　Tyndall's　thoughts　came　slowly　and　he　was　fatigued　he　said〃Well；　a　good　cup　of　coffee　will　make　me　think　faster。〃　In　conceding　this　practical　connection　between　mind　and　body；　every　〃spiritualist〃　philosopher　gives　away　his　case　whenever　he　rests　or　eats。
  The　statement　that　mind　is　a　function　of　the　organism　is　not　necessarily　〃materialistic。〃　The　body　is　a　living　thing　and　as　such　is　as　〃spiritualistic〃　as　life　itself。　Enzymes；　internal　secretions；　nervous　activities　are　the　products　of　cells　whose　powers　are　indeed　drawn　from　the　ocean　of　life。　To　prove　this　statement；　which　is　a　cardinal　thesis　of　this　book；　I　shall　adduce　facts　of　scientific　and　facts　of　common　knowledge。　One　might　start　with　the　statement　that　the　death　of　the　body　brings　about　the　abolition　of　mind　and　character；　but　this；　of　course；　proves　nothing；　since　it　might　well　be　that　the　body　was　a　lever　for　the　expression　of　mind　and　character；　and　with　its　disappearance　as　a　functioning　agent　such　expression　was　no　longer　possible。　It　is　convenient　to　divide　our　exposition　into　two　parts；　the　first　the　dependence　upon　proper　brain　function　and　structure；　and　the　second　the　dependence　upon　the　proper　health　of　other　organs。　For　it　is　not　true　that　mind　and　character　are　functions　of　the　brain　alone；　they　are　functions　of　the　entire　organism。　The　brain　is　simply　the　largest　and　most　active　of　the　organs　upon　which　the　mental　life　depends；　but　there　are　minute　organs；　as　we　shall　see；　upon　whose　activity　the　brain　absolutely　depends。　Any　injury　to　the　brain　may　destroy　or　seriously　impair　the　mentality　of　the　individual。　This　is　too　well　known　to　need　detailed　exposition。　Yet　some　cases　of　this　type　are　fundamental　in　the　exquisite　way　they　prove　（if　anything　can　be　proven）　the　dependence　of　mind　upon　bodily　structure。　In　some　cases　of　fracture　of　the　skull；　a　piece　of　bone　pressing　upon　the　brain　may　profoundly　alter　memory；　mood　and　character。　Removal　of　the　piece　of　bone　restores　the　mind　to　normality。　This　is　also　true　of　brain　tumor　of　certain　types；　for　example；　frontal　endotheliomata；　where　early　removal　of　the　growth　demonstrates　first　that　a　〃physical〃　agent　changes　mind　and　character；　and　second　that　a　〃physical〃　agent；　such　as　the　knife　of　the　surgeon；　may　act　to　reestablish　mentality。　In　cases　of　hydrocephalus　（or　water　on　the　brain）；　where　there　is　an　abnormal　secretion　of　cerebro…spinal　fluid　acting　to　increase　the　pressure　on　the　brain；　the　simple　expedient　of　withdrawing　the　fluid　by　lumbar　puncture　brings　about　normal　mental　life。　As　the　fluid　again　collects；　the　mental　life　becomes　cloudy；　and　the　character　alters　（irritability；　depressed　mood；　changed　purpose；　lowered　will）；　another　lumbar　puncture　and　presto！the　individual　is　for　a　time　made　over　more　completely　than　conversion　changes　a　sinner；and　more　easily。　Take　the　case　of　the　disease　known　as　General　Paresis；　officially　called　Dementia　Paralytica。　This　disease　is　caused　by　syphilis　and　is　one　of　its　late　results。　The　pathological　changes　are　widespread　throughout　the　brain　but　may　at　the　onset　be　confined　mostly　to　the　frontal　lobes。　The　very　first　change　may　beand　usually　isa　change　in　character！　The　man　hitherto　kind　and　gentle　becomes　irritable；　perhaps　even　brutal。　One　whose　sex　morals　have　been　of　the　most　conventional　kind；　a　loyal　husband；　suddenly　becomes　a　profligate；　reckless　and　debauched；　perhaps　even　perverted。　The　man　of　firm　purposes　and　indefatigable　industry　may　lose　his　grip　upon　the　ambitions　and　strivings　of　his　lifetime　and　become　an　inert　slacker；　to　the　amazement　of　his　associates。　Many　a　fine　character；　many　a　splendid　mind；　has　reached　a　lofty　height　and　then　crumbled　before　the　assaults　of　this　disease　upon　the　brain。　Philosopher；　poet；　artist；　statesman；　captain　of　industry；　handicraftsman；　peasant；　courtesan　and　housewife；all　are　lowered　to　the　same　level　of　dementia　and　destroyed　character　by　the　consequences　of　the　thickened　meninges；　the　altered　blood　vessels　and　the　injured　nerve　cells。　Now　and　then　one　is　fortunate　enough　to　treat　with　success　an　early　case　of　General　Paresis。　And　then　the　reversed　miracle　takes　place；　unfortunately　too　rarely！　The　disordered　mind；　the　altered　character；　leaps　upward　to　its　old　place；after　being　dosed　by　the　marvelous　drug　Salvarsan；　created　by　the　German　Jewish　scientist；　Paul　Ehrlich。　Of　extraordinary　interest　are　the　rare　cases　of　loss　of　personal　identity　seen　after　brain　injury；　say　in　war。　A　man　is　knocked　unconscious　by　a　blow　and　upon　restoration　of　consciousness　is　separated　from　that　past　in　which　his　ego　resides。　He　does　not　know　his　history　or　his　name；　and　that　continuity　of　the　〃self〃　so　deeply　prized　and　held　by　all　religions　to　be　part　of　his　immortality　is　gone。　Then　after　a　little　while；　a　few　days　or　weeks；　the　disarranged　neuronic　pathways　reestablish　themselves　as　usual；and　the　ego　comes　back　to　the　man。　One　might　cite　the　feeble…mindedness　that　results　from　meningitis；　brain　tumor；　brain　abscess；　brain　wounds；　etc。；　as　further　evidence　of　the　dependence　of　mind　upon　brain；　of　its　status　as　a　function　of　brain。　No　philosopher　seriously　doubts　that　equilibrium　and　movement　are　functions　of　the　brain；　and　yet　to　prove　this　there　is　no　evidence　of　any　other　kind　than　that　cited　to　prove　the　relationship　of　mind　to　brain。＇1＇　And　what　applies　to　the　intelligence　applies　as　forcibly　to　character；　for　purpose；　emotion；　mood；　instinct　and　will　are　altered　with　these　diseases。　＇1＇　Except　that　equilibrium　does　not　itself　judge　of　its　relationship　to　brain；　whereas　mind　is　the　sole　judge　of　its　relationship　and　dependence　on　brain。　Since　everything　in　the　world　is　a　mental　event；　mentality　cannot　be　dependent　upon　anything；　and　everything　depends　upon　mind　for　its　existence；　or　at　least　its　recognition。　But　we　get　nowhere　by　such　〃logic〃　gone　mad。　Apply　the　same　kind　of　reasoning　to　brain…mind；　body…mind　relationship　which　anatomists　and　physiologists　apply　to　other　functions；　and　one　can　no　longer　separate　body　and　mind。
  Interesting　as　is　the　relationship　between　mind　and　character　and　the　brain；　it　is　at　the　present　overshadowed　by　the　fascinating　relationship　between　these　psychical　activities　and　the　bodily　organs。　What　I　am　about　to　ci