enough：　　hence　the　institution　of　banners　and　flags。
  24。　　Gongs　and　drums；　banners　and　flags；　are　means　whereby
  the　ears　and　eyes　of　the　host　may　be　focused　on　one　particular
  point。
  ＇Chang　　　Yu　　　says：　　　　〃If　sight　　　and　　　hearing　　　converge
  simultaneously　on　the　same　object；　the　evolutions　of　as　many　as　a
  million　soldiers　will　be　like　those　of　a　single　man。〃！＇
  25。　　The　host　thus　forming　a　single　united　body；　　is　it
  impossible　either　for　the　brave　to　advance　alone；　　or　for　the
  cowardly　to　retreat　alone。
  ＇Chuang　Yu　quotes　a　saying：　〃Equally　guilty　are　those　who
  advance　against　orders　and　those　who　retreat　against　orders。〃　　Tu
  Mu　tells　a　story　in　this　connection　of　Wu　Ch‘i；　　when　he　was
  fighting　against　the　Ch‘in　State。　　Before　the　battle　had　begun；
  one　of　his　soldiers；　a　man　of　matchless　daring；　sallied　forth　by
  himself；　captured　two　heads　from　the　enemy；　and　returned　to　camp。
  Wu　Ch‘i　had　the　man　instantly　executed；　　whereupon　an　officer
  ventured　to　remonstrate；　saying：　　〃This　man　was　a　good　soldier；
  and　ought　not　to　have　been　beheaded。〃　　Wu　Ch‘i　replied：　　〃I　fully
  believe　he　was　a　good　soldier；　but　I　had　him　beheaded　because　he
  acted　without　orders。〃＇
  This　is　the　art　of　handling　large　masses　of　men。
  26。　　In　night…fighting；　then；　make　much　use　of　signal…fires
  and　drums；　　and　in　fighting　by　day；　of　flags　and　banners；　　as　a
  means　of　influencing　the　ears　and　eyes　of　your　army。
  ＇Ch‘en　Hao　alludes　to　Li　Kuang…pi's　night　ride　to　Ho…yang　at
  the　head　of　500　mounted　men；　they　made　such　an　imposing　display
  with　torches；　that　though　the　rebel　leader　Shih　Ssu…ming　had　a
  large　army；　he　did　not　dare　to　dispute　their　passage。＇
  27。　　A　whole　army　may　be　robbed　of　its　spirit；
  ＇〃In　war；〃　says　Chang　Yu；　〃if　a　spirit　of　anger　can　be　made
  to　pervade　all　ranks　of　an　army　at　one　and　the　same　time；　　its
  onset　will　be　irresistible。　　Now　the　spirit　of　the　enemy's
  soldiers　will　be　keenest　when　they　have　newly　arrived　on　the
  scene；　　and　it　is　therefore　our　cue　not　to　fight　at　once；　but　to
  wait　until　their　ardor　and　enthusiasm　have　worn　off；　　and　then
  strike。　　It　is　in　this　way　that　they　may　be　robbed　of　their　keen
  spirit。〃　　　Li　Ch‘uan　and　others　tell　an　anecdote　（to　be　found　in
  the　TSO　CHUAN；　year　10；　ss。　1）　of　Ts‘ao　Kuei；　a　protege　of　Duke
  Chuang　of　Lu。　　The　latter　State　was　attacked　by　Ch‘i；　　and　the
  duke　was　about　to　join　battle　at　Ch‘ang…cho；　after　the　first　roll
  of　the　enemy's　drums；　when　Ts‘ao　said：　　〃Not　just　yet。〃　　　Only
  after　their　drums　had　beaten　for　the　third　time；　did　he　give　the
  word　for　attack。　　Then　they　fought；　and　the　men　of　Ch‘i　were
  utterly　defeated。　　Questioned　afterwards　by　the　Duke　as　to　the
  meaning　of　his　delay；　　Ts‘ao　Kuei　replied：　　　〃In　battle；　　a
  courageous　spirit　is　everything。　　Now　the　first　roll　of　the　drum
  tends　to　create　this　spirit；　but　with　the　second　it　is　already　on
  the　wane；　and　after　the　third　it　is　gone　altogether。　　I　attacked
  when　their　spirit　was　gone　and　ours　was　at　its　height。　　Hence　our
  victory。〃　　　Wu　Tzu　（chap。　4）　puts　〃spirit〃　first　among　the　　〃four
  important　influences〃　　in　war；　and　continues：　　〃The　value　of　a
  whole　armya　mighty　host　of　a　million　menis　dependent　on　one
  man　alone：　　such　is　the　influence　of　spirit！〃＇
  a　commander…in…chief　may　be　robbed　of　his　presence　of　mind。
  ＇Chang　Yu　says：　　〃Presence　of　mind　is　the　general's　most
  important　asset。　　It　is　the　quality　which　enables　him　to
  discipline　disorder　and　to　inspire　courage　into　the　panic…
  stricken。〃　　　The　great　general　Li　Ching　（A。D。　　571…649）　　has　a
  saying：　　〃Attacking　does　not　merely　consist　in　assaulting　walled
  cities　or　striking　at　an　army　in　battle　array；　it　must　include
  the　art　of　assailing　the　enemy's　mental　equilibrium。〃＇
  28。　　Now　a　solider's　spirit　is　keenest　in　the　morning；
  ＇Always　provided；　I　suppose；　that　he　has　had　breakfast。　　At
  the　battle　of　the　Trebia；　the　Romans　were　foolishly　allowed　to
  fight　　　fasting；　　whereas　Hannibal's　men　had　breakfasted　　　at
  their　leisure。　　See　Livy；　XXI；　liv。　8；　lv。　1　and　8。＇
  by　noonday　it　has　begun　to　flag；　and　in　the　evening；　his　mind　is
  bent　only　on　returning　to　camp。
  29。　　A　clever　general；　therefore；　avoids　an　army　when　its
  spirit　is　keen；　but　attacks　it　when　it　is　sluggish　and　inclined
  to　return。　　This　is　the　art　of　studying　moods。
  30。　　Disciplined　and　calm；　to　await　the　appearance　of
  disorder　and　hubbub　amongst　the　enemy：this　is　the　art　of
  retaining　self…possession。
  31。　　To　be　near　the　goal　while　the　enemy　is　still　far　from
  it；　to　wait　at　ease　while　the　enemy　is　toiling　and　struggling；　to
  be　well…fed　while　the　enemy　is　famished：this　is　the　art　of
  husbanding　one's　strength。
  32。　　To　refrain　from　intercepting　an　enemy　whose　banners　are
  in　perfect　order；　to　refrain　from　attacking　an　army　drawn　up　in
  calm　　　and　confident　array：this　is　the　art　　　of　　　studying
  circumstances。
  33。　　It　is　a　military　axiom　not　to　advance　uphill　against
  the　enemy；　nor　to　oppose　him　when　he　comes　downhill。
  34。　　Do　not　pursue　an　enemy　who　simulates　flight；　　do　not
  attack　soldiers　whose　temper　is　keen。
  35。　　Do　not　swallow　bait　offered　by　the　enemy。
  ＇Li　Ch‘uan　and　Tu　Mu；　with　extraordinary　inability　to　see　a
  metaphor；　take　these　words　quite　literally　of　food　and　drink　that
  have　been　poisoned　by　the　enemy。　　Ch‘en　Hao　and　Chang　Yu
  carefully　point　out　that　the　saying　has　a　wider　application。＇
  Do　not　interfere　with　an　army　that　is　returning　home。
  ＇The　commentators　explain　this　rather　singular　piece　of
  advice　by　saying　that　a　man　whose　heart　is　set　on　returning　home
  will　fight　to　the　death　against　any　attempt　to　bar　his　way；　　and
  is　therefore　too　dangerous　an　opponent　to　be　tackled。　　Chang　Yu
  quotes　the　words　of　Han　Hsin：　　〃Invincible　is　the　soldier　who
  hath　his　desire　and　returneth　homewards。〃　　A　marvelous　tale　is
  told　of　Ts‘ao　Ts‘ao's　courage　and　resource　in　ch。　1　of　the　SAN
  KUO　CHI：　　In　198　A。D。；　he　was　besieging　Chang　Hsiu　in　Jang；　　when
  Liu　Piao　sent　reinforcements　with　a　view　to　cutting　off　Ts‘ao's
  retreat。　　The　latter　was　obligbed　to　draw　off　his　troops；　only　to
  find　himself　hemmed　in　between　two　enemies；　who　were　guarding
  each　outlet　of　a　narrow　pass　in　which　he　had　engaged　himself。　　In
  this　desperate　plight　Ts‘ao　waited　until　nightfall；　when　he　bored
  a　tunnel　into　the　mountain　side　and　laid　an　ambush　in　it。　　As
  soon　as　the　whole　army　had　passed　by；　the　hidden　troops　fell　on
  his　rear；　　while　Ts‘ao　himself　turned　and　met　his　pursuers　in
  front；　　so　that　they　were　thrown　into　confusion　and　annihilated。
  Ts‘ao　Ts‘ao　said　afterwards：　　〃The　brigands　tried　to　check　my
  army　in　its　retreat　and　brought　me　to　battle　in　a　desperate
  position：　　hence　I　knew　how　to　overcome　them。〃＇
  36。　　When　you　surround　an　army；　leave　an　outlet　free。
  ＇This　does　not　mean　that　the　enemy　is　to　be　allowed　to
  escape。　　The　object；　as　Tu　Mu　puts　it；　is　〃to　make　him　believe
  that　there　is　a　road　to　safety；　and　thus　prevent　his　fighting
  with　the　courage　of　despair。〃　　Tu　Mu　adds　pleasantly：　　　〃After
  that；　you　may　crush　him。〃＇
  Do　not　press　a　desperate　foe　too　hard。
  ＇Ch‘en　Hao　quotes　the　saying：　　　〃Birds　and　beasts　when
  brought　to　bay　will　use　their　claws　and　teeth。〃　　Chang　Yu　says：
  〃If　your　adversary　has　burned　his　boats　and　destroyed　his
  cooking…pots；　and　is　ready　to　stake　all　on　the　issue　of　a　battle；
  he　must　not　be　pushed　to　extremities。〃　　Ho　Shih　illustrates　the
  meaning　by　a　story　taken　from　the　life　of　Yen…ch‘ing。　　That
  general；　together　with　his　colleague　Tu　Chung…wei　was　surrounded
  by　a　vastly　superior　army　of　Khitans　in　the　year　945　A。D。　　The
  country　was　bare　and　desert…like；　and　the　little　Chinese　force
  was　soon　in　dire　straits　for　want　of　water。　　The　wells　they　bored
  ran　dry；　and　the　men　were　reduced　to　squeezing　lumps　of　mud　and
  sucking　out　the　moisture。　　Their　ranks　thinned　rapidly；　until　at
  last　Fu　Yen…ch‘ing　exclaimed：　　〃We　are　desperate　men。　　Far　better
  to　die　for　our　country　than　to　go　with　fettered　hands　into
  captivity！〃　　　A　strong　gale　happened　to　be　blowing　from　the
  northeast　and　darkening　the　air　with　dense　clouds　of　sandy　dust。
  To　Chung…wei　was　for　waiting　until　this　had　abated　before
  deciding　on　a　final　attack；　but　luckily　another　officer；　Li　Shou…
  cheng　by　name；　　was　quicker　to　see　an　opportunity；　　and　said：
  〃They　are　many　and　we　are　few；　but　in　the　midst　of　this　sandstorm
  our　numbers　will　not　be　discernible；　victory　will　go　to　the
  strenuous　fighter；　　and　the　wind　will　be　our　best　　　ally。〃
  Accordingly；　　Fu　Yen…ch‘ing　made　a　sudden　and　wholly　unexpected
  onslaught　with　his　cavalry；　routed　the　barbarians　and　succeeded
  in　breaking　through　to　safety。＇
  37。　　Such　is　the　art　of　warfare。
  ＇1＇　　See　Col。　Henderson；　op。　cit。　vol。