If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.
General," said the commander of the delinquent brigade, "I am persuaded that any further display of valor by my troops will bring them into collision with the enemy.
To this military attitude of the soul we give the name of Heroism... It is a self-trust which slights the restraints of prudence, in the plenitude of its energy and power to repair the harms it may suffer. The hero is a mind of such balance that no disturbances can shake his will.
If I determine the enemy's disposition of forces while I have no perceptible form, I can concentrate my forces while the enemy is fragmented. The pinnacle of military deployment approaches the formless: if it is formless, then even the deepest spy cannot discern it nor the wise make plans against it.
In two weeks the sheeplike masses of any country can be worked up by the newspapers into such a state of excited fury that men are prepared to put on uniforms and kill and be killed, for the sake of the sordid ends of a few interested parties. Compulsory military service seems to me the most disgraceful symptom of that deficiency in personal dignity from which civilized mankind is suffering today.