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; if twice as numerous,
to divide our army into two.

It is the rule in war, if ten times the enemy's strength, surround them; if five times, attack them; if double, be able to divide them; if equal, engage them; if fewer, defend against them; if weaker, be able to avoid them.

Rule 1, on page 1 of the book of war, is: "Do not march on Moscow". Various people have tried it, Napoleon and Hitler, and it is no good. That is the first rule. I do not know whether your Lordships will know Rule 2 of war. It is: "Do not go fighting with your land armies in China". It is a vast country, with no clearly defined objectives.

Always mystify, mislead, and surprise the enemy, if possible; and when you strike and overcome him, never let up in the pursuit so long as your men have strength to follow; for an army routed, if hotly pursued, becomes panic-stricken, and can then be destroyed by half their number. The other rule is, never fight against heavy odds, if by any possible maneuvering you can hurl your own force on only a part, and that the weakest part, of your enemy and crush it. Such tactics will win every time, and a small army may thus destroy a large one in detail, and repeated victory will make it invincible.

I have no doubt but that every State bordering upon the enemy, will apply for a proper force, to protect them against their ravages. To comply with these demands, will hard the safety of the whole army. Divide your force,, and you will fall a prey in every quarter; and, I am persuaded, were you to adopt the plan which would be most flattering to the wishes of the people, it would be so far from affording them that protection and security which they promise themselves, that it would become one of the principal causes of the enemy's making inroads, and committing depredations upon them.

In war, the moral is to the physical as ten to one.

故用兵之法，十則圍之，五則攻之，倍則分之， 敵則能戰之，少則能守之，不若則能避之。

In conformity with all that has been said on the subject up to the present, two fundamental principles reign throughout the whole plan of the war, and serve as a guide for everything else.

The first is: to reduce the weight of the enemy’s power into as few centres of gravity as possible, into one if it can be done; again, to confine the attack against these centres of force to as few principal undertakings as possible, to one if possible; lastly, to keep all secondary undertakings as subordinate as possible. In a word, the first principle is, to act concentrated as much as possible.

The second principle runs thus to act as swiftly as possible; therefore, to allow of no delay or detour without sufficient reason.

The way to do battle is the same whether it is a battle between one individual and another or a battle between one army and another. You should observe reflectively, with overall awareness of the large picture as well as precise attention to small details.

Soldiers defending a country at war are not subject to the rules of procedure designed for court trials. For example, if a soldier encounters an enemy, under internationally agreed upon rules of war, that soldier can take whatever action is necessary to protect himself and neutralize his enemy, whether it involves capturing and detaining the enemy or killing him on the spot.

If his forces are united, separate them.

We must carry the war into every corner the enemy happens to carry it: to his home, to his centers of entertainment; a total war. It is necessary to prevent him from having a moment of peace, a quiet moment outside his barracks or even inside; we must attack him wherever he may be; make him feel like a cornered beast wherever he may move. Then his moral fiber shall begin to decline. He will even become more beastly, but we shall notice how the signs of decadence begin to appear.

"There are many enemies" applies when you are fighting one against many. Draw both sword and companion sword and assume a wide-stretched left and right attitude. The spirit is to chase the enemies around from side to side, even though they come from all four directions. Observe their attacking order, and go to meet first those who attack first. Sweep your eyes around broadly, carefully examining the attacking order, and cut left and right alternately with your swords. Waiting is bad. Always quickly re-assume your attitudes to both sides, cut the enemies down as they advance, crushing them in the direction from which they attack. Whatever you do, you must drive the enemy together, as if tying a line of fishes, and when they are seen to be piled up, cut them down strongly without giving them room to move.

In tactics, action is the governing rule of war.