There are five dangerous faults which may affect a general: recklessness, which leads to destruction; cowardice, which leads to capture; a hasty temper, which can be provoked by insults; a delicacy of honour, which is sensitive to shame; over-solicitude for his men, which exposes him to worry and trouble.
It is a doctrine of war not to assume the enemy will not come, but rather to rely on one's readiness to meet him; not to presume that he will not attack, but rather to make one's self invincible.
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.
Hostile armies may face each other for years, striving for the victory which is decided in a single day. This being so, to remain in ignorance of the enemy's condition simply because one grudges the outlay of a hundred ounces of silver in honors and emoluments, is the height of inhumanity.
There are roads which must not be followed, armies which must not be attacked, towns which must not be besieged, positions which must not be contested, commands of the sovereign which must not be obeyed.
You cannot know if you will be successful or not. You can only prepare for battle and it must be done with all of your heart and with all of your consciousness. In that manner, you will have an edge.
With regard to precipitous heights, if you are beforehand with your adversary, you should occupy the raised and sunny spots, and there wait for him to come up.
We cannot enter into alliances until we are acquainted with the designs of our neighbors. We are not fit to lead an army on the march unless we are familiar with the face of the country.