The　Ethics　＇Part　5＇
  （Ethica　Ordine　Geometrico　Demonstrata）
  by　Benedict　de　Spinoza
  Translated　by　R。　H。　M。　Elwes
  PART　V：　　Of　the　Power　of　the　Understanding；　or　of　Human　Freedom
  PREFACE
  At　length　I　pass　to　the　remaining　portion　of　my　Ethics；　which　is　concerned
  with　the　way　leading　to　freedom。　I　shall　therefore　treat　therein　of　the
  power　of　the　reason；　showing　how　far　the　reason　can　control　the　emotions；
  and　what　is　the　nature　of　Mental　Freedom　or　Blessedness；　we　shall　then　be
  able　to　see；　how　much　more　powerful　the　wise　man　is　than　the　ignorant。
  It　is　no　part　of　my　design　to　point　out　the　method　and　means　whereby　the
  understanding　may　be　perfected；　nor　to　show　the　skill　whereby　the　body　may
  be　so　tended；　as　to　be　capable　of　the　due　performance　of　its　functions。　The
  latter　question　lies　in　the　province　of　Medicine；　the　former　in　the　province
  of　Logic。　Here；　therefore；　I　repeat；　I　shall　treat　only　of　the　power　of　the
  mind；　or　of　reason；　and　I　shall　mainly　show　the　extent　and　nature　of　its
  dominion　over　the　emotions；　for　their　control　and　moderation。　That　we　do
  not　possess　absolute　dominion　over　them；　I　have　already　shown。　Yet　the
  Stoics　have　thought；　that　the　emotions　depended　absolutely　on　our　will；　and
  that　we　could　absolutely　govern　them。　But　these　philosophers　were　compelled；
  by　the　protest　of　experience；　not　from　their　own　principles；　to　confess；
  that　no　slight　practice　and　zeal　is　needed　to　control　and　moderate　them：
  and　this　someone　endeavoured　to　illustrate　by　the　example　（if　I　remember
  rightly）　of　two　dogs；　the　one　a　house…dog　and　the　other　a　hunting…dog。　For
  by　long　training　it　could　be　brought　about；　that　the　house…dog　should　become
  accustomed　to　hunt；　and　the　hunting…dog　to　cease　from　running　after　hares。
  To　this　opinion　Descartes　not　a　little　inclines。　For　he　maintained；　that　the
  soul　or　mind　is　specially　united　to　a　particular　part　of　the　brain；　namely；
  to　that　part　called　the　pineal　gland；　by　the　aid　of　which　the　mind　is
  enabled　to　feel　all　the　movements　which　are　set　going　in　the　body；　and　also
  external　objects；　and　which　the　mind　by　a　simple　act　of　volition　can　put　in
  motion　in　various　ways。　He　asserted；　that　this　gland　is　so　suspended　in　the
  midst　of　the　brain；　that　it　could　be　moved　by　the　slightest　motion　of　the
  animal　spirits：　further；　that　this　gland　is　suspended　in　the　midst　of　the
  brain　in　as　many　different　manners；　as　the　animal　spirits　can　impinge
  thereon；　and；　again；　that　as　many　different　marks　are　impressed　on　the　said
  gland；　as　there　are　different　external　objects　which　impel　the　animal
  spirits　towards　it；　whence　it　follows；　that　if　the　will　of　the　soul　suspends
  the　gland　in　a　position；　wherein　it　has　already　been　suspended　once　before
  by　the　animal　spirits　driven　in　one　way　or　another；　the　gland　in　its　turn
  reacts　on　the　said　spirits；　driving　and　determining　them　to　the　condition
  wherein　they　were；　when　repulsed　before　by　a　similar　position　of　the　gland。
  He　further　asserted；　that　every　act　of　mental　volition　is　united　in　nature
  to　a　certain　given　motion　of　the　gland。　For　instance；　whenever　anyone
  desires　to　look　at　a　remote　object；　the　act　of　volition　causes　the　pupil　of
  the　eye　to　dilate；　whereas；　if　the　person　in　question　had　only　thought　of
  the　dilatation　of　the　pupil；　the　mere　wish　to　dilate　it　would　not　have
  brought　about　the　result；　inasmuch　as　the　motion　of　the　gland；　which　serves
  to　impel　the　animal　spirits　towards　the　optic　nerve　in　a　way　which　would
  dilate　or　contract　the　pupil；　is　not　associated　in　nature　with　the　wish　to
  dilate　or　contract　the　pupil；　but　with　the　wish　to　look　at　remote　or　very
  near　objects。　Lastly；　he　maintained　that；　although　every　motion　of　the
  aforesaid　gland　seems　to　have　been　united　by　nature　to　one　particular
  thought　out　of　the　whole　number　of　our　thoughts　from　the　very　beginning　of
  our　life；　yet　it　can　nevertheless　become　through　habituation　associated　with
  other　thoughts；　this　he　endeavours　to　prove　in　the　Passions　de　l'ame；　I。　50。
  He　thence　concludes；　that　there　is　no　soul　so　weak；　that　it　cannot；　under
  proper　direction；　acquire　absolute　power　over　its　passions。　For　passions　as
  defined　by　him　are　〃perceptions；　or　feelings；　or　disturbances　of　the　soul；
  which　are　referred　to　the　soul　as　species；　and　which　（mark　the　expression）
  are　produced；　preserved；　and　strengthened　through　some　movement　of　the
  spirits。〃　（Passion　del　l'ame；I。27。）　But；　seeing　that　we　can　join　any　motion
  of　the　gland；　or　consequently　of　the　spirits；　to　any　volition；　the
  determination　of　the　will　depends　entirely　on　our　own　powers；　if；　therefore；
  we　determine　our　will　with　sure　and　firm　decisions　in　the　direction　to　which
  we　wish　our　actions　to　tend；　and　associate　the　motions　of　the　passions　which
  we　wish　to　acquire　with　the　said　decisions；　we　shall　acquire　an　absolute
  dominion　over　our　passions。　Such　is　the　doctrine　of　this　illustrious
  philosopher　（in　so　far　as　I　gather　it　from　his　own　words）；　it　is　one
  which；　had　it　been　less　ingenious；　I　could　hardly　believe　to　have　proceeded
  from　so　great　a　man。　Indeed；　I　am　lost　in　wonder；　that　a　philosopher；　who
  had　stoutly　asserted；　that　he　would　draw　no　conclusions　which　do　not　follow
  from　self…evident　premisses；　and　would　affirm　nothing　which　he　did　not
  clearly　and　distinctly　perceive；　and　who　had　so　often　taken　to　task　the
  scholastics　for　wishing　to　explain　obscurities　through　occult　qualities；
  could　maintain　a　hypothesis；　beside　which　occult　qualities　are　commonplace。
  What　does　he　understand；　I　ask；　by　the　union　of　the　mind　and　the　body？　What
  clear　and　distinct　conception　has　he　got　of　thought　in　most　intimate　union
  with　a　certain　particle　of　extended　matter？　Truly　I　should　like　him　to
  explain　this　union　through　its　proximate　cause。　What　clear　and　distinct
  conception　has　he　got　of　thought　in　most　intimate　union　with　a　certain
  particle　of　extended　matter？　What　clear　and　distinct　conception　has　he　got
  of　thought　in　most　intimate　union　with　a　certain　particle　of　extended
  matter？　But　he　had　so　distinct　a　conception　of　mind　being　distinct　from
  body；　that　he　could　not　assign　any　particular　cause　of　the　union　between　the
  two；　or　of　the　mind　itself；　but　was　obliged　to　have　recourse　to　the　cause　of
  the　whole　universe；　that　is　to　God。　Further；　I　should　much　like　to　know；
  what　degree　of　motion　the　mind　can　impart　to　this　pineal　gland；　and　with
  what　force　can　it　hold　it　suspended？　For　I　am　in　ignorance；　whether　this
  gland　can　be　agitated　more　slowly　or　more　quickly　by　the　mind　than　by　the
  animal　spirits；　and　whether　the　motions　of　the　passions；　which　we　have
  closely　united　with　firm　decisions；　cannot　be　again　disjoined　therefrom　by
  physical　causes；　in　which　case　it　would　follow　that；　although　the　mind
  firmly　intended　to　face　a　given　danger；　and　had　united　to　this　decision　the
  motions　of　boldness；　yet　at　the　sight　of　the　danger　the　gland　might　become
  suspended　in　a　way；　which　would　preclude　the　mind　thinking　of　anything
  except　running　away。　In　truth；　as　there　is　no　common　standard　of　volition
  and　motion；　so　is　there　no　comparison　possible　between　the　powers　of　the
  mind　and　the　power　or　strength　of　the　body；　consequently　the　strength　of　one
  cannot　in　any　wise　be　determined　by　the　strength　of　the　other。　We　may　also
  add；　that　there　is　no　gland　discoverable　in　the　midst　of　the　brain；　so
  placed　that　it　can　thus　easily　be　set　in　motion　in　so　many　ways；　and　also
  that　all　the　nerves　are　not　prolonged　so　far　as　the　cavities　of　the　brain。
  Lastly；　I　omit　all　the　assertions　which　he　makes　concerning　the　will　and　its
  freedom；　inasmuch　as　I　have　abundantly　proved　that　his　premisses　are　false。
  Therefore；　since　the　power　of　the　mind；　as　I　have　shown　above；　is　defined　by
  the　understanding　only；　we　shall　determine　solely　by　the　knowledge　of　the
  mind　the　remedies　against　the　emotions；　which　I　believe　all　have　had
  experience　of；　but　do　not　accurately　observe　or　distinctly　see；　and　from　the
  same　basis　we　shall　deduce　all　those　conclusions；　which　have　regard　to　the
  mind's　blessedness。
  AXIOMS。
  I。　If　two　contrary　actions　be　started　in　the　same　subject；　a　change　must
  necessarily　take　place；　either　in　both；　or　in　one　of　the　two；　and　continue
  until　they　cease　to　be　contrary。
  II。　The　power　of　an　effect　is　defined　by　the　power　of　its　cause；　in　so　far
  as　its　essence　is　explained　or　defined　by　the　essence　of　its　cause。　（This
  axiom　is　evident　from　III。vii。）
  PROPOSITIONS。
  Prop。I。　Even　as　thoughts　and　the　ideas　of　things　are　arranged
  and　associated　in　the　mind；　so　are　the　modifications　of　body　or
  the　images　of　things　precisely　in　the　same　way　arranged　and
  associated　in　the　body。
  Proof。…　The　ord