sight　is　being　stimulated；　though　in　reality　not　so　stimulated；　that
  we　sometimes　erroneously　declare　ourselves　to　see；　or　that；　from　the
  fact　that　touch　announces　two　movements；　we　think　that　the　one
  object　is　two。　For；　as　a　rule；　the　governing　sense　affirms　the
  report　of　each　particular　sense；　unless　another　particular　sense；　more
  authoritative；　makes　a　contradictory　report。　In　every　case　an
  appearance　presents　itself；　but　what　appears　does　not　in　every　case
  seem　real；　unless　when　the　deciding　faculty　is　inhibited；　or　does
  not　move　with　its　proper　motion。　Moreover；　as　we　said　that　different
  men　are　subject　to　illusions；　each　according　to　the　different
  emotion　present　in　him；　so　it　is　that　the　sleeper；　owing　to　sleep；　and
  to　the　movements　then　going　on　in　his　sensory　organs；　as　well　as　to
  the　other　facts　of　the　sensory　process；　＇is　liable　to　illusion＇；　so
  that　the　dream　presentation；　though　but　little　like　it；　appears　as
  some　actual　given　thing。　For　when　one　is　asleep；　in　proportion　as　most
  of　the　blood　sinks　inwards　to　its　fountain　＇the　heart＇；　the　internal
  ＇sensory＇　movements；　some　potential；　others　actual　accompany　it
  inwards。　They　are　so　related　＇in　general＇　that；　if　anything　move　the
  blood；　some　one　sensory　movement　will　emerge　from　it；　while　if　this
  perishes　another　will　take　its　place；　while　to　one　another　also　they
  are　related　in　the　same　way　as　the　artificial　frogs　in　water　which
  severally　rise　＇in　fixed　succesion＇　to　the　surface　in　the　order　in
  which　the　salt　＇which　keeps　them　down＇　becomes　dissolved。　The
  residuary　movements　are　like　these：　they　are　within　the　soul
  potentially；　but　actualize　themselves　only　when　the　impediment　to
  their　doing　so　has　been　relaxed；　and　according　as　they　are　thus　set
  free；　they　begin　to　move　in　the　blood　which　remains　in　the　sensory
  organs；　and　which　is　now　but　scanty；　while　they　possess　verisimilitude
  after　the　manner　of　cloud…shapes；　which　in　their　rapid　metamorphoses
  one　compares　now　to　human　beings　and　a　moment　afterwards　to
  centaurs。　Each　of　them　is　however；　as　has　been　said；　the　remnant　of
  a　sensory　impression　taken　when　sense　was　actualizing　itself；　and　when
  this；　the　true　impression；　has　departed；　its　remnant　is　still
  immanent；　and　it　is　correct　to　say　of　it；　that　though　not　actually
  Koriskos；　it　is　like　Koriskos。　For　when　the　person　was　actually
  perceiving；　his　controlling　and　judging　sensory　faculty　did　not　call
  it　Koriskos；　but；　prompted　by　this　＇impression＇；　called　the　genuine
  person　yonder　Koriskos。　Accordingly；　this　sensory　impulse；　which；　when
  actually　perceiving；　it　＇the　controlling　faculty＇　describes　（unless
  completely　inhibited　by　the　blood）；　it　now　＇in　dreams＇　when
  quasi…perceiving；　receives　from　the　movements　persisting　in　the
  sense…organs；　and　mistakes　it…an　impulse　that　is　merely　like　the
  true　＇objective＇　impression…for　the　true　impression　itself；　while
  the　effect　of　sleep　is　so　great　that　it　causes　this　mistake　to　pass
  unnoticed。　Accordingly；　just　as　if　a　finger　be　inserted　beneath　the
  eyeball　without　being　observed；　one　object　will　not　only　present　two
  visual　images；　but　will　create　an　opinion　of　its　being　two　objects；
  while　if　it　＇the　finger＇　be　observed；　the　presentation　will　be　the
  same；　but　the　same　opinion　will　not　be　formed　of　it；　exactly　so　it
  is　in　states　of　sleep：　if　the　sleeper　perceives　that　he　is　asleep；　and
  is　conscious　of　the　sleeping　state　during　which　the　perception　comes
  before　his　mind；　it　presents　itself　still；　but　something　within　him
  speaks　to　this　effect：　'the　image　of　Koriskos　presents　itself；　but　the
  real　Koriskos　is　not　present'；　for　often；　when　one　is　asleep；　there　is
  something　in　consciousness　which　declares　that　what　then　presents
  itself　is　but　a　dream。　If；　however；　he　is　not　aware　of　being　asleep；
  there　is　nothing　which　will　contradict　the　testimony　of　the　bare
  presentation。
  That　what　we　here　urge　is　true；　i。e。　that　there　are　such
  presentative　movements　in　the　sensory　organs；　any　one　may　convince
  himself；　if　he　attends　to　and　tries　to　remember　the　affections　we
  experience　when　sinking　into　slumber　or　when　being　awakened。　He　will
  sometimes；　in　the　moment　of　awakening；　surprise　the　images　which
  present　themselves　to　him　in　sleep；　and　find　that　they　are　really
  but　movements　lurking　in　the　organs　of　sense。　And　indeed　some　very
  young　persons；　if　it　is　dark；　though　looking　with　wide　open　eyes；
  see　multitudes　of　phantom　figures　moving　before　them；　so　that　they
  often　cover　up　their　heads　in　terror。
  From　all　this；　then；　the　conclusion　to　be　drawn　is；　that　the　dream
  is　a　sort　of　presentation；　and；　more　particularly；　one　which　occurs　in
  sleep；　since　the　phantoms　just　mentioned　are　not　dreams；　nor　is　any
  other　a　dream　which　presents　itself　when　the　sense…perceptions　are
  in　a　state　of　freedom。　Nor　is　every　presentation　which　occurs　in　sleep
  necessarily　a　dream。　For　in　the　first　place；　some　persons　＇when
  asleep＇　actually；　in　a　certain　way；　perceive　sounds；　light；　savour；
  and　contact；　feebly；　however；　and；　as　it　were；　remotely。　For　there
  have　been　cases　in　which　persons　while　asleep；　but　with　the　eyes
  partly　open；　saw　faintly　in　their　sleep　（as　they　supposed）　the　light
  of　a　lamp；　and　afterwards；　on　being　awakened；　straightway　recognized
  it　as　the　actual　light　of　a　real　lamp；　while；　in　other　cases；
  persons　who　faintly　heard　the　crowing　of　cocks　or　the　barking　of
  dogs　identified　these　clearly　with　the　real　sounds　as　soon　as　they
  awoke。　Some　persons；　too；　return　answers　to　questions　put　to　them　in
  sleep。　For　it　is　quite　possible　that；　of　waking　or　sleeping；　while　the
  one　is　present　in　the　ordinary　sense；　the　other　also　should　be　present
  in　a　certain　way。　But　none　of　these　occurrences　should　be　called　a
  dream。　Nor　should　the　true　thoughts；　as　distinct　from　the　mere
  presentations；　which　occur　in　sleep　＇be　called　dreams＇。　The　dream
  proper　is　a　presentation　based　on　the　movement　of　sense　impressions；
  when　such　presentation　occurs　during　sleep；　taking　sleep　in　the　strict
  sense　of　the　term。
  There　are　cases　of　persons　who　in　their　whole　lives　have　never　had　a
  dream；　while　others　dream　when　considerably　advanced　in　years；
  having　never　dreamed　before。　The　cause　of　their　not　having　dreams
  appears　somewhat　like　that　which　operates　in　the　case　of　infants；　and
  ＇that　which　operates＇　immediately　after　meals。　It　is　intelligible
  enough　that　no　dream…presentation　should　occur　to　persons　whose
  natural　constitution　is　such　that　in　them　copious　evaporation　is　borne
  upwards；　which；　when　borne　back　downwards；　causes　a　large　quantity　of
  motion。　But　it　is　not　surprising　that；　as　age　advances；　a　dream　should
  at　length　appear　to　them。　Indeed；　it　is　inevitable　that；　as　a　change
  is　wrought　in　them　in　proportion　to　age　or　emotional　experience；　this
  reversal　＇from　non…dreaming　to　dreaming＇　should　occur　also。
  THE　END
  。