If your opponent is of choleric temperament, seek to irritate him.

The general that hearkens to my counsel and acts upon it, will conquer: let such a one be retained in command! The general that hearkens not to my counsel nor acts upon it, will suffer defeat: - let such a one be dismissed!.

The general who loses makes but few calculations beforehand.

The general who wins the battle makes many calculations in his temple before the battle is fought.

Hence it is a subject of inquiry which can on no account be neglected. It is a matter of life and death, a road either to safety or to ruin.

The art of war is of vital importance to the State.

Pretend inferiority and encourage his arrogance.

Note: 'If his forces are united, separate them' is also interpreted: 'If sovereign and subject are in accord, put division between them.'.

Attack him where he is unprepared, appear where you are not expected. If he is taking his ease, give him no rest. Pretend to be weak, that he may grow arrogant. If your opponent is temperamental, seek to irritate him. If he is in superior strength, evade him.

If your enemy is secure at all points, be prepared for him.

Though effective, appear to be ineffective.

Even though you are competent, appear to be incompetent.

A military operation involves deception.

Hence, when we are able to attack, we must seem unable when using our forces, we must appear inactive when we are near, we must make the enemy believe we are far away when far away, we must make him believe we are near. All men can see these tactics whereby I conquer, but what none can see is the strategy out of which victory is evolved.

Sun zhus the art of war 3 principles