o　the　north　bank　from　the　east　of　the　Yellow　River？　But　instead　you　engaged　in　the　attack　of　the　Pass　for　many　days　before　crossing　to　the　north　bank。〃

And　he　replied；　〃The　rebels　first　held　the　Pass。　Had　I　forthwith　taken　the　east　side　of　the　Yellow　River；　the　rebels　would　have　defended　the　camps　one　by　one　and　mustered　at　all　the　ferries；　and　I　should　never　have　got　across　to　the　west　side　（which　was　also　the　north　bank　of　River　Wei）。　So　I　massed　troops　against　Tong　Pass　and　made　the　rebels　guard　the　south　bank　of　River　Wei；　so　that　the　north　bank　was　left　open。　Thus　Xu　Huang　and　Zhu　Ling　could　move　there；　and　I　was　able　later　to　cross　over　to　join　them。　Then　I　made　the　raised　road　and　the　mud　rampart　to　deceive　the　enemy　and　cause　them　to　think　I　was　weak　and　thus　embolden　them　up　to　the　point　of　attacking　without　proper　preparation。　Then　I　used　the　clever　device　of　causing　dissension　in　their　ranks　and　was　able　in　one　day　to　destroy　the　stored　up　energy　of　all　their　forces。　'It　was　a　thunder　clap　before　you　could　cover　your　ears。'　Yes；　indeed；　the　mutations　of　the　art　of　war　can　be　called　infinite。〃

〃But　one　thing　more　puzzled　us；〃　said　the　officers；　〃and　we　ask　you　to　explain　it。　When　you　heard　the　enemy　was　reinforced；　you　seemed　to　grow　happier。　Why　was　that？〃

〃Because　Tong　Pass　is　distant　from　Xuchang。　If　the　rebels　had　taken　advantage　of　all　defensible　points　and　held　them；　they　could　not　have　been　quelled　in　less　than　a　couple　of　years。　When　they　came　on　altogether；　they　made　a　multitude　but　they　were　not　unanimous。　They　easily　quarreled　and；　disunited；　were　easily　overe。　So　I　had　reason　to　rejoice　that　they　came　on　altogether。〃

〃Indeed　no　one　can　equal　you　in　strategy；〃　said　his　officers；　bowing　low　before　him。

〃Still；　remem