circumstances？
  Theaet。　Yes；　they　do。
  Str。　But　surely　that　which　may　be　present　or　may　be　absent　will　be
  admitted　by　them　to　exist？
  Theaet。　Certainly。
  Str。　And；　allowing　that　justice；　wisdom；　the　other　virtues；　and
  their　opposites　exist；　as　well　as　a　soul　in　which　they
  inhere；　do　they
  affirm　any　of　them　to　be　visible　and　tangible；　or　are　they　all
  invisible？
  Theaet。　They　would　say　that　hardly　any　of　them　are　visible。
  Str。　And　would　they　say　that　they　are　corporeal？
  Theaet。　They　would　distinguish：　the　soul　would　be　said　by　them　to
  have　a　body；　but　as　to　the　other　qualities　of　justice；
  wisdom；　and　the
  like；　about　which　you　asked；　they　would　not　venture　either　to　deny
  their　existence；　or　to　maintain　that　they　were　all　corporeal。
  Str。　Verily；　Theaetetus；　I　perceive　a　great　improvement　in
  them；　the
  real　aborigines；　children　of　the　dragon's　teeth；　would　have　been
  deterred　by　no　shame　at　all；　but　would　have　obstinately　asserted
  that　nothing　is　which　they　are　not　able　to　squeeze　in　their　hands。
  Theaet。　That　is　pretty　much　their　notion。
  Str。　Let　us　push　the　question；　for　if　they　will　admit　that
  any；　even
  the　smallest　particle　of　being；　is　incorporeal；　it　is　enough；　they
  must　then　say　what　that　nature　is　which　is　common　to　both　the
  corporeal　and　incorporeal；　and　which　they　have　in　their　mind's　eye
  when　they　say　of　both　of　them　that　they　〃are。〃　Perhaps　they　may　be
  in　a　difficulty；　and　if　this　is　the　case；　there　is　a　possibility
  that　they　may　accept　a　notion　of　ours　respecting　the　nature　of
  being；　having　nothing　of　their　own　to　offer。
  Theaet。　What　is　the　notion？　Tell　me；　and　we　shall　soon　see。
  Str。　My　notion　would　be；　that　anything　which　possesses　any　sort　of
  power　to　affect　another；　or　to　be　affected　by　another；　if　only　for　a
  single　moment；　however　trifling　the　cause　and　however　slight　the
  effect；　has　real　existence；　and　I　hold　that　the　definition
  of　being　is
  simply　power　of
  Theaet。　They　accept　your　suggestion；　having　nothing　better　of
  their　own　to　offer。
  Str。　Very　good；　perhaps　we；　as　well　as　they；　may　one　day　change
  our　minds；　but；　for　the　present；　this　may　be　regarded　as　the
  understanding　which　is　established　with　them。
  Theaet。　Agreed。
  Str。　Let　us　now　go　to　the　friends　of　ideas；　of　their　opinions；
  too；　you　shall　be　the　interpreter。
  Theaet。　I　will。
  Str。　To　them　we　say…You　would　distinguish　essence　from　generation？
  Theaet。　〃Yes；〃　they　reply。
  Str。　And　you　would　allow　that　we　participate　in
  generation；　with　the
  body；　and　through　perception；　but　we　participate　with　the
  soul　through
  in　true　essence；　and　essence　you　would　affirm　to　be　always　the　same
  and　immutable；　whereas　generation　or　becoming　varies？
  Theaet。　Yes；　that　is　what　we　should　affirm。
  Str。　Well；　fair　sirs；　we　say　to　them；　what　is　this　participation；
  which　you　assert　of　both？　Do　you　agree　with　our　recent　definition？
  Theaet。　What　definition？
  Str。　We　said　that　being　was　an　active　or　passive　energy；
  arising　out
  of　a　certain　power　which　proceeds　from　elements　meeting　with　one
  another。　Perhaps　your　cars；　Theaetetus；　may　fail　to　catch　their
  answer；　which　I　recognize　because　I　have　been　accustomed　to　hear　it。
  Theaet。　And　what　is　their　answer？
  Str。　They　deny　the　truth　of　what　we　were　just　now；　saying　to　the
  aborigines　about　existence。
  Theaet。　What　was　that？
  Str。　Any　power　of　doing　or　suffering　in　a　degree　however　slight
  was　held　by　us　to　be　a　sufficient　definition　of　being？
  Theaet。　True。
  Str。　They　deny　this；　and　say　that　the　power　of　doing　or
  suffering　is
  confined　to　becoming；　and　that　neither　power　is　applicable　to　being。
  Theaet。　And　is　there　not　some　truth　in　what　they　say？
  Str。　Yes；　but　our　reply　will　be　that　we　want　to　ascertain　from
  them　more　distinctly；　whether　they　further　admit　that　the　soul
  knows；　and　that　being　or　essence　is　known。
  Theaet。　There　can　be　no　doubt　that　they　say　so。
  Str。　And　is　knowing　and　being　known；　doing　or　suffering；
  or　both；　or
  is　the　one　doing　and　the　other　suffering；　or　has　neither　any　share
  in　either？
  Theaet。　Clearly；　neither　has　any　share　in　either；　for　if　they　say
  anything　else；　they　will　contradict　themselves。
  Str。　I　understand；　but　they　will　allow　that　if　to　know　is　active；
  then；　of　course；　to　be　known　is　passive。　And　on　this　view
  being；　in　so
  far　as　it　is　known；　is　acted　upon　by　knowledge；　and　is　therefore　in
  motion；　for　that　which　is　in　a　state　of　rest　cannot　be　acted　upon；
  as　we　affirm。
  Theaet。　True。
  Str。　And；　O　heavens；　can　we　ever　be　made　to　believe　that　motion
  and　life　and　soul　and　mind　are　not　present　with　perfect　being？　Can
  we　imagine　that；　being　is　devoid　of　life　and　mind；　and
  exists　in　awful
  unmeaningness　an　everlasting　fixture？
  Theaet。　That　would　be　a　dreadful　thing　to　admit；　Stranger。
  Str。　But　shall　we　say　that　has　mind　and　not　life？
  Theaet。　How　is　that　possible？
  Str。　Or　shall　we　say　that　both　inhere　in　perfect　being；　but　that
  it　has　no　soul　which　contains　them？
  Theaet。　And　in　what　other　way　can　it　contain　them？
  Str。　Or　that　being　has　mind　and　life　and　soul；　but　although
  endowed　with　soul　remains　absolutely　unmoved？
  Theaet。　All　three　suppositions　appear　to　me　to　be　irrational。
  Str。　Under　being；　then；　we　must　include　motion；　and　that　which　is
  moved。
  Theaet。　Certainly。
  Str。　Then；　Theaetetus；　our　inference　is；　that　if　there　is
  no　motion；
  neither　is　there　any　mind　anywhere；　or　about　anything　or　belonging
  to　any　one。
  Theaet。　Quite　true。
  Str。　And　yet　this　equally　follows；　if　we　grant　that　all　things　are
  in　motion…upon　this　view　too　mind　has　no　existence。
  Theaet。　How　so？
  Str。　Do　you　think　that　sameness　of　condition　and　mode　and　subject
  could　ever　exist　without　a　principle　of　rest？
  Theaet。　Certainly　not。
  Str。　Can　you　see　how　without　them　mind　could　exist；　or　come　into
  existence　anywhere？
  Theaet。　No。
  Str。　And　surely　contend　we　must　in　every　possible　way　against　him
  who　would　annihilate　knowledge　and　reason　and　mind；　and　yet　ventures
  to　speak　confidently　about　anything。
  Theaet。　Yes；　with　all　our　might。
  Str。　Then　the　philosopher；　who　has　the　truest　reverence　for　these
  qualities；　cannot　possibly　accept　the　notion　of　those　who
  say　that　the
  whole　is　at　rest；　either　as　unity　or　in　many　forms：　and　he　will　be
  utterly　deaf　to　those　who　assert　universal　motion。　As　children　say
  entreatingly　〃Give　us　both。〃　so　he　will　include　both　the　moveable
  and　immoveable　in　his　definition　of　being　and　all。
  Theaet。　Most　true。
  Str。　And　now；　do　we　seem　to　have　gained　a　fair　notion　of　being？
  Theaet。　Yes　truly。
  Str。　Alas；　Theaetetus；　methinks　that　we　are　now　only　beginning　to
  see　the　real　difficulty　of　the　enquiry　into　the　nature　of　it。
  Theaet。　What　do　you　mean？
  Str。　O　my　friend；　do　you　not　see　that　nothing　can　exceed　out
  ignorance；　and　yet　we　fancy　that　we　are　saying　something　good？
  Theaet。　I　certainly　thought　that　we　were；　and　I　do　not　at　all
  understand　how　we　never　found　out　our　desperate　case。
  Str。　Reflect：　after　having　made；　these　admissions；　may　we　not　be
  justly　asked；　the　same　questions　which　we　ourselves　were　asking　of
  those　who　said　that　all　was　hot　and　cold？
  Theaet。　What　were　they？　Will　you　recall　them　to　my　mind？
  Str。　To　be　sure；　I　will　remind　you　of　them；　by　putting　the　same
  questions；　to　you　which　I　did　to　them；　and　then　we　shall　get　on。
  Theaet。　True。
  Str。　Would　you　not　say　that　rest　and　motion　are　in　the　most　entire
  opposition　to　one　another？
  Theaet。　Of　course。
  Str。　And　yet　you　would　say　that　both　and　either　of　them
  equally　are？
  Theaet。　I　should。
  Str。　And　when　you　admit　that　both　or　either　of　them　are；
  do　you　mean
  to　say　that　both　or　either；　of　them　are　in　motion？
  Theaet。　Certainly　not。
  Str。　Or　do　you　wish　to　imply　that　they　are　both　at　rest；　when　you
  say　that　they　are？
  Theaet。　Of　course　not。
  Str。　Then　you　conceive　of　being　as　some　third　and　distinct　nature；
  under　which　rest　and　motion　are　alike　included；　and；　observing　that
  they　both　participate　in　being；　you　declare　that　they　are。
  Theaet。　Truly　we　seem　to　have　an　intimation　that　being　is
  some　third
  thing；　when　we　say　that　rest　and　motion　are。
  Str。　Then　being　is　not　the　combination　of　rest　and　motion；　but
  something　different　from　them。
  Theaet。　So　it　would　appear。
  Str。　Being；　then；　according　to　its　own　nature；　is　neither　in
  motion　nor　at　rest。
  Theaet。　That　is　very　much　the　truth。
  Str。　Where；　then；　is　a　man　to　look　for　help　who　would　have
  any　clear
  or　fixed　notion　of　being　in　his　mind？
  Theaet。　Where；　indeed？
  Str。　I　scarcely　think　that　he　can　look　anywhere；　for　that　which　is
  not　in　motion　must　be　at　rest；　and　again；　that　which　is　not　at　rest
  must　be　in　motion；　but　being　is　placed　outside　of　both　these
  classes。　Is　this　possible？
  Theaet。　Utterly　impossible。
  Str。　Here；　then；　is　another　thing　which　we　ought　to　bear　in　mind。
  Theaet。　What？
  Str。　When　we　were　asked　to　what　we　were　to　assign　the
  appellation　of
  not…being；　we　were　in　the　greatest　difficulty：…do　you　remember