engaging　picture　of　the　famous　general　Wu　Ch‘i；　　from　whose
  treatise　on　war　I　have　frequently　had　occasion　to　quote：　　　〃He
  wore　the　same　clothes　and　ate　the　same　food　as　the　meanest　of　his
  soldiers；　　refused　to　have　either　a　horse　to　ride　or　a　mat　to
  sleep　on；　carried　his　own　surplus　rations　wrapped　in　a　parcel；
  and　shared　every　hardship　with　his　men。　　One　of　his　soldiers　was
  suffering　from　an　abscess；　and　Wu　Ch‘i　himself　sucked　out　the
  virus。　　The　soldier's　mother；　hearing　this；　began　wailing　and
  lamenting。　　Somebody　asked　her；　saying：　　'Why　do　you　cry？　　　Your
  son　is　only　a　common　soldier；　and　yet　the　commander…in…chief
  himself　has　sucked　the　poison　from　his　sore。'　　The　woman　replied；
  'Many　years　ago；　　Lord　Wu　performed　a　similar　service　for　my
  husband；　who　never　left　him　afterwards；　and　finally　met　his　death
  at　the　hands　of　the　enemy。　　And　now　that　he　has　done　the　same　for
  my　son；　he　too　will　fall　fighting　I　know　not　where。'〃　　Li　Ch‘uan
  mentions　the　Viscount　of　Ch‘u；　who　invaded　the　small　state　of
  Hsiao　during　the　winter。　　The　Duke　of　Shen　said　to　him：　　〃Many　of
  the　soldiers　are　suffering　severely　from　the　cold。〃　　So　he　made　a
  round　of　the　whole　army；　comforting　and　encouraging　the　men；　　and
  straightway　they　felt　as　if　they　were　clothed　in　garments　lined
  with　floss　silk。＇
  26。　　If；　however；　you　are　indulgent；　but　unable　to　make　your
  authority　　　felt；　　kind…hearted；　　but　unable　to　enforce　　　your
  commands；　　and　incapable；　moreover；　of　quelling　disorder：　　　then
  your　soldiers　must　be　likened　to　spoilt　children；　　they　are
  useless　for　any　practical　purpose。
  ＇Li　Ching　once　said　that　if　you　could　make　your　soldiers
  afraid　of　you；　they　would　not　be　afraid　of　the　enemy。　　Tu　Mu
  recalls　an　instance　of　stern　military　discipline　which　occurred
  in　219　A。D。；　when　Lu　Meng　was　occupying　the　town　of　Chiang…ling。
  He　had　given　stringent　orders　to　his　army　not　to　molest　the
  inhabitants　nor　take　anything　from　them　by　force。　　Nevertheless；
  a　certain　officer　serving　under　his　banner；　who　happened　to　be　a
  fellow…townsman；　　ventured　to　appropriate　a　bamboo　hat　belonging
  to　one　of　the　people；　in　order　to　wear　it　over　his　regulation
  helmet　as　a　protection　against　the　rain。　　Lu　Meng　considered　that
  the　fact　of　his　being　also　a　native　of　Ju…nan　should　not　be
  allowed　to　palliate　a　clear　breach　of　discipline；　and　accordingly
  he　ordered　his　summary　execution；　the　tears　rolling　down　his
  face；　　however；　　as　he　did　so。　　This　act　of　severity　filled　the
  army　with　wholesome　awe；　and　from　that　time　forth　even　articles
  dropped　in　the　highway　were　not　picked　up。＇
  27。　　If　we　know　that　our　own　men　are　in　a　condition　to
  attack；　but　are　unaware　that　the　enemy　is　not　open　to　attack；　　we
  have　gone　only　halfway　towards　victory。
  ＇That　is；　　Ts‘ao　Kung　says；　〃the　issue　in　this　case　is
  uncertain。〃＇
  28。　　If　we　know　that　the　enemy　is　open　to　attack；　　but　are
  unaware　that　our　own　men　are　not　in　a　condition　to　attack；　　we
  have　gone　only　halfway　towards　victory。
  ＇Cf。　III。　ss。　13　（1）。＇
  29。　　If　we　know　that　the　enemy　is　open　to　attack；　and　also
  know　that　our　men　are　in　a　condition　to　attack；　but　are　unaware
  that　the　nature　of　the　ground　makes　fighting　impracticable；　　we
  have　still　gone　only　halfway　towards　victory。
  30。　　Hence　the　experienced　soldier；　once　in　motion；　is　never
  bewildered；　once　he　has　broken　camp；　he　is　never　at　a　loss。
  ＇The　reason　being；　according　to　Tu　Mu；　that　he　has　taken　his
  measures　so　thoroughly　as　to　ensure　victory　beforehand。　　〃He　does
  not　move　recklessly；〃　says　Chang　Yu；　〃so　that　when　he　does　move；
  he　makes　no　mistakes。〃＇
  31。　　Hence　the　saying：　　If　you　know　the　enemy　and　know
  yourself；　　your　victory　will　not　stand　in　doubt；　　if　you　know
  Heaven　and　know　Earth；　you　may　make　your　victory　complete。
  ＇Li　Ch‘uan　sums　up　as　follows：　　〃Given　a　knowledge　of　three
  thingsthe　affairs　of　men；　the　seasons　of　heaven　and　the　natural
  advantages　of　earth；　　victory　will　invariably　crown　　　your
  battles。〃＇
  ＇1＇　　See　〃Pensees　de　Napoleon　1er；〃　no。　47。
  ＇2＇　　〃The　Science　of　War；〃　chap。　2。
  ＇3＇　　〃Aids　to　Scouting；〃　p。　xii。
  …
  XI。　　THE　NINE　SITUATIONS
  1。　　Sun　Tzu　said：　　The　art　of　war　recognizes　nine　varieties
  of　ground：　　　（1）　　Dispersive　ground；　　（2）　　facile　ground；　　（3）
  contentious　ground；　（4）　open　ground；　（5）　ground　of　intersecting
  highways；　（6）　serious　ground；　（7）　difficult　ground；　（8）　hemmed…in
  ground；　（9）　desperate　ground。
  2。　　When　a　chieftain　is　fighting　in　his　own　territory；　it　is
  dispersive　ground。
  ＇So　called　because　the　soldiers；　being　near　to　their　homes
  and　anxious　to　see　their　wives　and　children；　are　likely　to　seize
  the　opportunity　afforded　by　a　battle　and　scatter　in　every
  direction。　　〃In　their　advance；〃　observes　Tu　Mu；　〃they　will　lack
  the　valor　of　desperation；　and　when　they　retreat；　they　will　find
  harbors　of　refuge。〃＇
  3。　　When　he　has　penetrated　into　hostile　territory；　but　to　no
  great　distance；　it　is　facile　ground。
  ＇Li　Ch‘uan　and　Ho　Shih　say　〃because　of　the　facility　for
  retreating；〃　　　and　　　the　　　other　　　commentators　　　give　　　　similar
  explanations。　　Tu　Mu　remarks：　　〃When　your　army　has　crossed　the
  border；　you　should　burn　your　boats　and　bridges；　in　order　to　make
  it　clear　to　everybody　that　you　have　no　hankering　after　home。〃＇
  4。　　Ground　the　possession　of　which　imports　great　advantage
  to　either　side；　is　contentious　ground。
  ＇Tu　Mu　defines　the　ground　as　ground　〃to　be　contended　for。〃
  Ts‘ao　Kung　says：　　　〃ground　on　which　the　few　and　the　weak　can
  defeat　the　many　and　the　strong；〃　such　as　〃the　neck　of　a　pass；〃
  instanced　　　by　Li　Ch‘uan。　　Thus；　　Thermopylae　was　　　of　　　this
  classification　because　the　possession　of　it；　even　for　a　few　days
  only；　　meant　holding　the　entire　invading　army　in　check　and　thus
  gaining　invaluable　time。　　Cf。　Wu　Tzu；　ch。　V。　　ad　init。：　　　〃For
  those　who　have　to　fight　in　the　ratio　of　one　to　ten；　　there　is
  nothing　better　than　a　narrow　pass。〃　　When　Lu　Kuang　was　returning
  from　his　triumphant　expedition　to　Turkestan　in　385　A。D。；　and　had
  got　as　far　as　I…ho；　laden　with　spoils；　Liang　Hsi；　　administrator
  of　Liang…chou；　taking　advantage　of　the　death　of　Fu　Chien；　King　of
  Ch‘in；　　plotted　against　him　and　was　for　barring　his　way　into　the
  province。　　Yang　Han；　　governor　of　Kao…ch‘ang；　　counseled　him；
  saying：　　　〃Lu　Kuang　is　fresh　from　his　victories　in　the　west；　　and
  his　soldiers　are　vigorous　and　mettlesome。　　If　we　oppose　him　in
  the　shifting　sands　of　the　desert；　we　shall　be　no　match　for　him；
  and　we　must　therefore　try　a　different　plan。　　Let　us　hasten　to
  occupy　the　defile　at　the　mouth　of　the　Kao…wu　pass；　thus　cutting
  him　off　from　supplies　of　water；　　and　when　his　troops　are
  prostrated　with　thirst；　we　can　dictate　our　own　terms　without
  moving。　　Or　if　you　think　that　the　pass　I　mention　is　too　far　off；
  we　could　make　a　stand　against　him　at　the　I…wu　pass；　　which　is
  nearer。　　The　cunning　and　resource　of　Tzu…fang　himself　would　be
  expended　in　vain　against　the　enormous　strength　of　these　two
  positions。〃　　　Liang　Hsi；　　refusing　to　act　on　this　advice；　　was
  overwhelmed　and　swept　away　by　the　invader。＇
  5。　　Ground　on　which　each　side　has　liberty　of　movement　is
  open　ground。
  ＇There　are　various　interpretations　of　the　Chinese　adjective
  for　this　type　of　ground。　　Ts‘ao　Kung　says　it　means　　　〃ground
  covered　with　a　network　of　roads；〃　like　a　chessboard。　　Ho　Shih
  suggested：　　〃ground　on　which　intercommunication　is　easy。〃＇
  6。　　Ground　which　forms　the　key　to　three　contiguous　states；
  ＇Ts‘au　Kung　defines　this　as：　　〃Our　country　adjoining　the
  enemy's　and　a　third　country　conterminous　with　both。〃　　Meng　Shih
  instances　the　small　principality　of　Cheng；　which　was　bounded　on
  the　north…east　by　Ch‘i；　on　the　west　by　Chin；　and　on　the　south　by
  Ch‘u。＇
  so　that　he　who　occupies　it　first　has　most　of　the　Empire　at　his
  command；
  ＇The　belligerent　who　holds　this　dominating　position　can
  constrain　most　of　them　to　become　his　allies。＇
  is　a　ground　of　intersecting　highways。
  7。　　When　an　army　has　penetrated　into　the　heart　of　a　hostile
  country；　leaving　a　number　of　fortified　cities　in　its　rear；　it　is
  serious　ground。
  ＇Wang　Hsi　explains　the　name　by　saying　that　〃when　an　army　has
  reached　such　a　point；　its　situation　is　serious。〃＇
  8。　　Mountain　forests；
  ＇Or　simply　〃forests。〃＇
  rugged　steeps；　　marshes　and　fensall　country　that　is　hard　to
  traverse：　　this　is　difficult　ground。
  9。　　Ground　which　is　reached　through　narrow　gorges；　and　from
  which　we　can　only　retire　by　tortuous　paths；　so　that　a　small
  number　of　the　enemy　would　suffice　to　crush　a　large　body　of　our
  men：　　this　is　hemmed　in　ground。
  10。　　Ground　on　which　we　can　only　be　saved　from　destruction
  by