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Art of War Chapter 10 Summary: Terrain

What Chapter 10 actually argues

The six terrains come first. Accessible ground can be freely crossed by both sides, so occupy the raised sunny spots first and guard your supply line. Entangling ground can be left but is hard to re-occupy: sally out if the enemy is unprepared, but if he is prepared and you fail, return is impossible and disaster follows. Temporising ground is where neither side gains by moving first — so do not move, even if offered an attractive bait; withdraw instead and strike when the opponent has come half way out. Narrow passes should be occupied first and strongly garrisoned; if the opponent holds one already, follow him only if it is weakly held. Precipitous heights should be taken before the adversary; if he holds them, do not follow, but retreat and entice him away. And at great distances with equal strength, provoking battle is not easy and fighting will be to your disadvantage.

Sun Tzu then names the second six and draws a sharp line under them: an army is exposed to six several calamities, not arising from natural causes, but from faults for which the general is responsible. Flight, when a force is hurled against another ten times its size. Insubordination, when the soldiers are too strong and their officers too weak. Collapse, when officers are too strong and the soldiers too weak. Ruin, when senior officers are angry and insubordinate and give battle on their own account out of resentment. Disorganisation, when the general is weak and without authority and his orders are unclear. Rout, when a general cannot estimate the opponent's strength and sends an inferior force against a larger one. He calls these six ways of courting defeat.

Two independent duties follow. First, the natural formation of the country is the soldier's best ally, but estimating the adversary, controlling the forces of victory and shrewdly calculating difficulties and distances is what constitutes the test of a great general. Second, and more radical: if fighting is sure to result in victory you must fight even if the ruler forbids it, and if it will not, you must not fight even at the ruler's bidding. The general who advances without coveting fame and retreats without fearing disgrace, whose only thought is to protect his country and do good service for his sovereign, is called the jewel of the kingdom.

The chapter's treatment of command is the warmest in the book and the most carefully qualified. Regard your soldiers as your children and they will follow you into the deepest valleys; look on them as your own beloved sons and they will stand by you even unto death. But if you are indulgent and unable to make your authority felt, kind-hearted but unable to enforce your commands, and incapable of quelling disorder, then your soldiers are like spoilt children and useless for any practical purpose. Sun Tzu then builds his final knowledge argument in three steps — knowing your own capacity is half of victory, knowing the opponent as well is still only half, and knowing that the ground makes fighting impracticable is the third piece — before extending the Chapter 3 maxim to its full form.

Key lines from the Giles translation

These are quoted verbatim from Lionel Giles’ 1910 translation, which is in the public domain:

Now an army is exposed to six several calamities, not arising from natural causes, but from faults for which the general is responsible.

Regard your soldiers as your children, and they will follow you into the deepest valleys; look on them as your own beloved sons, and they will stand by you even unto death.

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.

One modern application: keep a list of your own failure modes

The six calamities are the most practical list in The Art of War, because every one of them is self-inflicted and therefore fixable. Translated out of military language they are: taking on something far beyond your capacity, letting strong people operate without capable oversight, putting capable oversight over people who cannot deliver, allowing senior people to act on private grievance, giving unclear instructions with no authority behind them, and misjudging the size of what you are up against. Nobody does these to you.

Written down, they become an audit you can actually run. Take any effort that failed and identify which of the six it was. The value is not the label — it is that the six are recurring, so the pattern in your own list tells you which one you are prone to, and that is the one to design against.

The instruction about disobeying the ruler is worth taking seriously as well, because Sun Tzu attaches a condition that is easy to skip. He does not license independent judgement in general. He licenses it for someone who advances without coveting fame and retreats without fearing disgrace — that is, someone whose judgement is not contaminated by how the decision will make them look. Without that clause the passage is just a permission slip.

Where Chapter 10 sits in the 13 chapters

The 13 chapters are a single argument, not thirteen essays: Chapters 1 to 6 establish assessment, cost, the ranking of methods, security, force and concentration; Chapters 7 to 12 apply them to movement, adaptation, observation, ground and restraint; Chapter 13 supplies the information all of it depends on. For the whole arc in one place, read The Art of War explained, or take the printable 13-chapter summary with you. Background on the text, its dating and its translation history is available at Wikipedia.

Read Chapter 10 as a lesson, not a page

LearnTzu turns each of the 13 chapters into short daily lessons with a journal prompt that applies the idea to a decision you are actually facing — which is the difference between having read Sun Tzu and being able to use him.

Frequently asked questions

What is Chapter 10 of The Art of War about?

Chapter 10, Terrain, describes six kinds of ground and how to fight on each, then lists six calamities that destroy armies. Sun Tzu states that those six do not arise from natural causes but from faults for which the general is responsible.

What are the six kinds of terrain in The Art of War?

Accessible ground, entangling ground, temporising ground, narrow passes, precipitous heights, and positions at a great distance from the enemy. Each has a matching instruction about who should occupy it first and whether to engage.

What are the six calamities in Chapter 10?

Flight, insubordination, collapse, ruin, disorganisation and rout. They are caused respectively by attacking a force ten times your size, soldiers too strong for their officers, officers too strong for their soldiers, senior officers acting on resentment, a weak general with unclear orders, and misjudging the enemy strength.

Does Sun Tzu say to disobey the ruler?

In one specific case. If fighting is sure to bring victory you must fight even if the ruler forbids it, and if it is not you must not fight even at his bidding. He attaches a condition: this applies to the general who advances without coveting fame and retreats without fearing disgrace.