He will win who knows when to fight and when not to fight.

He who knows things, and in fighting puts his knowledge into practice, will win his battles. He who knows them not, nor practices them, will surely be defeated.

The Art of War is self-explanatory

Now a soldier's spirit is keenest in the morning; by noonday it has begun to flag; and in the evening, his mind is only on returning to camp.

The greatest victory is that which requires no battle.

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.

He who knows his enemy and himself well will not be defeated easily.