three　months　more。
  ＇These　were　great　mounds　or　ramparts　of　earth　heaped　up　to
  the　level　of　the　enemy's　walls　in　order　to　discover　the　weak
  points　in　the　defense；　and　also　to　destroy　the　fortified　turrets
  mentioned　in　the　preceding　note。＇
  5。　　The　general；　unable　to　control　his　irritation；　　will
  launch　his　men　to　the　assault　like　swarming　ants；
  ＇This　vivid　simile　of　Ts‘ao　Kung　is　taken　from　the　spectacle
  of　an　army　of　ants　climbing　a　wall。　　The　meaning　is　that　the
  general；　losing　patience　at　the　long　delay；　may　make　a　premature
  attempt　to　storm　the　place　before　his　engines　of　war　are　ready。＇
  with　the　result　that　one…third　of　his　men　are　slain；　　while　the
  town　still　remains　untaken。　　Such　are　the　disastrous　effects　of　a
  siege。
  ＇We　are　reminded　of　the　terrible　losses　of　the　Japanese
  before　Port　Arthur；　in　the　most　recent　siege　which　history　has　to
  record。＇
  6。　　Therefore　the　skillful　leader　subdues　the　enemy's　troops
  without　any　fighting；　he　captures　their　cities　without　laying
  siege　to　them；　　he　overthrows　their　kingdom　without　lengthy
  operations　in　the　field。
  ＇Chia　Lin　notes　that　he　only　overthrows　the　Government；　　but
  does　no　harm　to　individuals。　　The　classical　instance　is　Wu　Wang；
  who　after　having　put　an　end　to　the　Yin　dynasty　was　acclaimed
  〃Father　and　mother　of　the　people。〃＇
  7。　　With　his　forces　intact　he　will　dispute　the　mastery　of
  the　Empire；　and　thus；　without　losing　a　man；　his　triumph　will　be
  complete。
  ＇Owing　to　the　double　meanings　in　the　Chinese　text；　　the
  latter　part　of　the　sentence　is　susceptible　of　quite　a　different
  meaning：　　　〃And　thus；　the　weapon　not　being　blunted　by　use；　　its
  keenness　remains　perfect。〃＇
  This　is　the　method　of　attacking　by　stratagem。
  8。　　It　is　the　rule　in　war；　if　our　forces　are　ten　to　the
  enemy's　one；　to　surround　him；　if　five　to　one；　to　attack　him；
  ＇Straightway；　without　waiting　for　any　further　advantage。＇
  if　twice　as　numerous；　to　divide　our　army　into　two。
  ＇Tu　Mu　takes　exception　to　the　saying；　and　at　first　sight；
  indeed；　　it　appears　to　violate　a　fundamental　principle　of　war。
  Ts'ao　Kung；　however；　gives　a　clue　to　Sun　Tzu's　meaning：　　　〃Being
  two　to　the　enemy's　one；　we　may　use　one　part　of　our　army　in　the
  regular　way；　and　the　other　for　some　special　diversion。〃　　Chang　Yu
  thus　further　elucidates　the　point：　　〃If　our　force　is　twice　as
  numerous　as　that　of　the　enemy；　it　should　be　split　up　into　two
  divisions；　　one　to　meet　the　enemy　in　front；　and　one　to　fall　upon
  his　rear；　if　he　replies　to　the　frontal　attack；　he　may　be　crushed
  from　behind；　　if　to　the　rearward　attack；　he　may　be　crushed　in
  front。〃　　　This　is　what　is　meant　by　saying　that　'one　part　may　be
  used　in　the　regular　way；　　and　the　other　for　some　special
  diversion。'　　　Tu　Mu　does　not　understand　that　dividing　one's　army
  is　simply　an　irregular；　just　as　concentrating　it　is　the　regular；
  strategical　method；　　and　he　is　too　hasty　in　calling　this　a
  mistake。〃＇
  9。　　If　equally　matched；　we　can　offer　battle；
  ＇Li　Ch‘uan；　　followed　by　Ho　Shih；　　gives　the　following
  paraphrase：　　　〃If　attackers　and　attacked　are　equally　matched　in
  strength；　only　the　able　general　will　fight。〃＇
  if　slightly　inferior　in　numbers；　we　can　avoid　the　enemy；
  ＇The　meaning；　〃we　can　WATCH　the　enemy；〃　is　certainly　a　great
  improvement　on　the　above；　but　unfortunately　there　appears　to　be
  no　very　good　authority　for　the　variant。　　Chang　Yu　reminds　us　that
  the　saying　only　applies　if　the　other　factors　are　equal；　a　small
  difference　in　numbers　is　often　more　than　counterbalanced　by
  superior　energy　and　discipline。＇
  if　quite　unequal　in　every　way；　we　can　flee　from　him。
  10。　　Hence；　though　an　obstinate　fight　may　be　made　by　a　small
  force；　in　the　end　it　must　be　captured　by　the　larger　force。
  11。　　Now　the　general　is　the　bulwark　of　the　State；　　if　the
  bulwark　is　complete　at　all　points；　the　State　will　be　strong；　　if
  the　bulwark　is　defective；　the　State　will　be　weak。
  ＇As　Li　Ch‘uan　tersely　puts　it：　　〃Gap　indicates　deficiency；
  if　the　general's　ability　is　not　perfect　（i。e。　　if　he　is　not
  thoroughly　versed　in　his　profession）；　　his　army　will　　　lack
  strength。〃＇
  12。　　There　are　three　ways　in　which　a　ruler　can　bring
  misfortune　upon　his　army：
  13。　　（1）　　By　commanding　the　army　to　advance　or　to　retreat；
  being　ignorant　of　the　fact　that　it　cannot　obey。　　This　is　called
  hobbling　the　army。
  ＇Li　Ch‘uan　adds　the　comment：　　〃It　is　like　tying　together　the
  legs　of　a　thoroughbred；　so　that　it　is　unable　to　gallop。〃　　　One
  would　naturally　think　of　〃the　ruler〃　in　this　passage　as　being　at
  home；　　and　trying　to　direct　the　movements　of　his　army　from　a
  distance。　　But　the　commentators　understand　just　the　reverse；　　and
  quote　the　saying　of　T‘ai　Kung：　　　〃A　kingdom　should　not　be
  governed　from　without；　　and　army　should　not　be　directed　from
  within。〃　　　Of　course　it　is　true　that；　during　an　engagement；　　or
  when　in　close　touch　with　the　enemy；　the　general　should　not　be　in
  the　thick　of　his　own　troops；　but　a　little　distance　apart。
  Otherwise；　he　will　be　liable　to　misjudge　the　position　as　a　whole；
  and　give　wrong　orders。＇
  14。　　（2）　　By　attempting　to　govern　an　army　in　the　same　way　as
  he　administers　a　kingdom；　being　ignorant　of　the　conditions　which
  obtain　in　an　army。　　This　causes　restlessness　in　the　soldier's
  minds。
  ＇Ts‘ao　Kung's　note　is；　freely　translated：　　　〃The　military
  sphere　and　the　civil　sphere　are　wholly　distinct；　you　can't　handle
  an　army　in　kid　gloves。〃　　And　Chang　Yu　says：　　　〃Humanity　and
  justice　are　the　principles　on　which　to　govern　a　state；　but　not　an
  army；　　opportunism　and　flexibility；　　on　the　other　hand；　　are
  military　rather　than　civil　virtues　to　assimilate　the　governing　of
  an　army〃to　that　of　a　State；　understood。＇
  15。　　（3）　　　By　employing　the　officers　of　his　army　without
  discrimination；
  ＇That　is；　　he　is　not　careful　to　use　the　right　man　in　the
  right　place。＇
  through　ignorance　of　the　military　principle　of　adaptation　to
  circumstances。　　This　shakes　the　confidence　of　the　soldiers。
  ＇I　follow　Mei　Yao…ch‘en　here。　　The　other　commentators　refer
  not　to　the　ruler；　as　in　SS。　13；　14；　but　to　the　officers　he
  employs。　　Thus　Tu　Yu　says：　　〃If　a　general　is　ignorant　of　the
  principle　of　adaptability；　　he　must　not　be　entrusted　with　a
  position　of　authority。〃　　Tu　Mu　quotes：　　〃The　skillful　employer　of
  men　will　employ　the　wise　man；　the　brave　man；　the　covetous　man；
  and　the　stupid　man。　　For　the　wise　man　delights　in　establishing
  his　merit；　the　brave　man　likes　to　show　his　courage　in　action；　the
  covetous　man　is　quick　at　seizing　advantages；　and　the　stupid　man
  has　no　fear　of　death。〃＇
  16。　　But　when　the　army　is　restless　and　distrustful；　　trouble
  is　sure　to　come　from　the　other　feudal　princes。　　This　is　simply
  bringing　anarchy　into　the　army；　and　flinging　victory　away。
  17。　　Thus　we　may　know　that　there　are　five　essentials　for
  victory：　　（1）　He　will　win　who　knows　when　to　fight　and　when　not　to
  fight。
  ＇Chang　Yu　says：　　If　he　can　fight；　he　advances　and　takes　the
  offensive；　　if　he　cannot　fight；　he　retreats　and　remains　on　the
  defensive。　　He　will　invariably　conquer　who　knows　whether　it　is
  right　to　take　the　offensive　or　the　defensive。＇
  （2）　　　He　will　win　who　knows　how　to　handle　both　superior　and
  inferior　forces。
  ＇This　is　not　merely　the　general's　ability　to　estimate
  numbers　correctly；　as　Li　Ch‘uan　and　others　make　out。　　Chang　Yu
  expounds　the　saying　more　satisfactorily：　　〃By　applying　the　art　of
  war；　it　is　possible　with　a　lesser　force　to　defeat　a　greater；　　and
  vice　versa。　　The　secret　lies　in　an　eye　for　locality；　and　in　not
  letting　the　right　moment　slip。　　Thus　Wu　Tzu　says：　　　'With　a
  superior　force；　make　for　easy　ground；　with　an　inferior　one；　　make
  for　difficult　ground。'〃＇
  （3）　　He　will　win　whose　army　is　animated　by　the　same　spirit
  throughout　all　its　ranks。
  （4）　　　He　will　win　who；　prepared　himself；　waits　to　take　the
  enemy　unprepared。
  （5）　　　He　will　win　who　has　military　capacity　and　is　not
  interfered　with　by　the　sovereign。
  ＇Tu　Yu　quotes　Wang　Tzu　as　saying：　　〃It　is　the　sovereign's
  function　to　give　broad　instructions；　but　to　decide　on　battle　it
  is　the　function　of　the　general。〃　　It　is　needless　to　dilate　on　the
  military　disasters　which　have　been　caused　by　undue　interference
  with　operations　in　the　field　on　the　part　of　the　home　government。
  Napoleon　undoubtedly　owed　much　of　his　extraordinary　success　to
  the　fact　that　he　was　not　hampered　by　central　authority。＇
  18。　　Hence　the　saying：　　If　you　know　the　enemy　and　know
  yourself；　you　need　not　fear　the　result　of　a　hundred　battles。　　If
  you　know　yourself　but　not　the　enemy；　for　every　victory　gained　you
  will　also　suffer　a　defeat。
  ＇Li　Ch‘uan　c