Chapter 8. Variation and Adaptability,九变 focuses on the need for flexibility in your responses. It explains how to respond to shifting circumstances successfully.

Six Grounds & Troop's Actions - Sun Tzu

English: Sun Zi said: In a military campaign, the general first receive orders from his ruler. He then assembles the troops and mobilize the citizens. When on treacherous grounds, you must never encamp. When on focal ground, you must attempt to ally with neighboring states. When on isolated ground, you must not stay there. When on constricted ground, you must plan and strategise. When on death ground, you must fight relentlessly.

Modern: 孙子说：大凡用兵的法则，首将先领命与君主，后征集兵队，编成军团，出征时，若在“圯地”不可扎营，若在“衢地”应结交邻国，若在“绝地”不可久留，若在“围地”要巧出计谋，若在“死地”要拼死奋战。

Original: 孙子曰：凡用兵之法，将受命于君， 合军聚众，圯地无舍，衢地合交，绝地勿留，围地则谋，死地则战。

Importance of Being Adapting to Changing Situations & Terrain - Sun Tzu

English: There are some routes and paths that must not be taken. There are some armies and troops that must not be assaulted. There are some cities that must not be attacked. There are some grounds that must not be contested. There are some military orders that need not be obeyed. Thus, the general who knows how to vary and adapt to changing situations so as to gain advantages is one who is skilful in applying the art of war. The general who is familiar with the terrain but does not know how to vary and adapt to changing situations will not be able to take advantage of what that terrain has to offer. In military command, if the general cannot master the art of variations and adaptability, he will not be able to deploy his troops to maximum advantage despite understanding the five strategic considerations.

Modern: 有些道路不宜走，有些敌军不宜打，有些城池不宜攻，有些要地不宜争，有的国君命令可以不执行。所以，将帅能够精通以上各种机变的运用，就是懂得用兵。将帅 不能够精通机变的运用，虽然了解地形，也不能得到地利。将帅不能够精通机变的运用，虽然知道“五利”，也不能充分发挥军队的战斗能力。

Original: 途有所不由，军有所不击，城有所不攻，地有所不争，君命有所不受。故将通于九变之利者，知用兵矣；将不通于九变之利，虽知地形，不能得的之利矣；治兵不知九变之术，虽知五利，不能得人之用矣。

Why Factor Favourable & Unfavourable - Sun Tzu

English: Thus, the wise strategist will always weigh and consider the favourable and unfavourable factors in his deliberations. By factoring the favourable factors, the mission can be accomplished with confidence. By factoring the unfavourable factors, disasters and crises can be averted.

Modern: 所以，聪明的将帅在考虑问题时，必定会兼顾到利害两方面条件。考虑到利，可以提高胜算，成功的信心。考虑到害，可以避免祸患和排除疑虑。

Original: 是故智者之虑，必杂于利害。杂于利，而务可信也；杂于害，而患可解也。

Dealing with Warlords - Sun Tzu

English: Succumb the neighbouring warlords through the use of intimidation and threats. Harass and wear down the neighbouring warlords through incessant creation of troubles and activities. Hasten and direct the movements of the neighbouring warlords through the offer of benefits and baits.

Modern: 要使各国诸侯屈服，就用诸侯最害怕的事威胁他；要使各国诸侯劳役，就用他不得不去做的事去驱使他；要使各国诸侯趋向你要的方向，就用小利去引诱他。

Original: 是故诸侯者以害，役诸侯者以业，趋诸侯者以利。

Preparedness - Sun Tzu

English: Thus, in the conduct of war, one must not rely on the failure of the enemy to come, but on the readiness of oneself to engage him. One must not rely on the failure of the enemy to attack, but on the ability of oneself to build an invincible defence.

Modern: 用兵之法是，不要寄望敌人不会来，而要依靠自己，充分军备，严阵以待；不要寄望敌人不会进攻，而要依靠自己，使自己不易攻破。

Original: 故用兵之法，无恃其不来，恃吾有以待也；无恃其不攻，恃吾有所不可攻也。

Dangerous Traits of Generals-Sun Tzu

English: Thus, there are five dangers that will plague any general. If he is reckless, he can be killed. If he is cowardly and desperate to live, he can be captured. If he is easily angered, he can be provoked. If he is sensitive to honour, he can be insulted. If he is overly compassionate to people, he can be disturbed and harassed. These five characteristics are the greatest pitfalls and mistakes of a general and the cause of disasters in any military operation. The destruction of an army and the deaths of generals are caused by these five dangers, thus they should be examined thoroughly.

Modern: 将帅有因性格上的缺陷而造成的危险；有勇无谋，只知道拼死，可能被诱杀；贪生怕死，临阵畏怯，可能被俘虏；急躁易怒，可能因被羞辱而败亡；在乎名声，可能 受不了羞辱而败亡；一味爱民爱士卒，可以容易被烦扰。以上五点是将帅可能范下的错，而会殃及兵队。军队覆灭，将帅被杀，都是由着五种危险引起，所以不可不 慎重，不可不深思。

Original: 故将有五危：必死，可杀也；必生，可虏也；忿速，可侮也；廉洁，可辱也；爱民，可烦也。此五者，将之过也，用兵之灾也。覆军杀将，必以五危，不可不察也。

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