resent　any　such　aspersion　on　these　historic　names：　　〃I　Yin　and　Lu
  Ya；〃　　he　says；　〃were　not　rebels　against　the　Government。　　Hsia
  could　not　employ　the　former；　hence　Yin　employed　him。　　Yin　could
  not　employ　the　latter；　hence　Hou　employed　him。　　Their　great
  achievements　were　all　for　the　good　of　the　people。〃　　Ho　Shih　is
  also　indignant：　　〃How　should　two　divinely　inspired　men　such　as　I
  and　Lu　have　acted　as　common　spies？　　Sun　Tzu's　mention　of　them
  simply　means　that　the　proper　use　of　the　five　classes　of　spies　is
  a　matter　which　requires　men　of　the　highest　mental　caliber　like　I
  and　Lu；　whose　wisdom　and　capacity　qualified　them　for　the　task。
  The　above　words　only　emphasize　this　point。〃　　Ho　Shih　believes
  then　that　the　two　heroes　are　mentioned　on　account　of　their
  supposed　skill　in　the　use　of　spies。　　But　this　is　very　weak。＇
  27。　　Hence　it　is　only　the　enlightened　ruler　and　the　wise
  general　who　will　use　the　highest　intelligence　of　the　army　for
  purposes　of　spying　and　thereby　they　achieve　great　results。
  ＇Tu　Mu　closes　with　a　note　of　warning：　　〃Just　as　water；　which
  carries　a　boat　from　bank　to　bank；　may　also　be　the　means　of
  sinking　it；　so　reliance　on　spies；　while　production　of　great
  results；　is　oft…times　the　cause　of　utter　destruction。〃＇
  Spies　are　a　most　important　element　in　water；　because　on　them
  depends　an　army's　ability　to　move。
  ＇Chia　Lin　says　that　an　army　without　spies　is　like　a　man　with
  ears　or　eyes。＇
  ＇1＇　　〃Aids　to　Scouting；〃　p。　2。
  ＇2＇　　〃Marshal　Turenne；〃　p。　311。
  End