If you are strong, appear weak. But if you are weak, appear strong.

Of all those in the army close to the commander none is more intimate than the secret agent; of all rewards none more liberal than those given to secret agents; of all matters none is more confidential than those relating to secret operations.

He must be able to mystify his officers and men by false reports and appearances, and thus keep them in total ignorance.

He who wishes to fight must first count the cost

Do not engage an enemy more powerful than you. And if it is unavoidable and you do have to engage, then make sure you engage it on your terms, not on your enemy's terms.

Attack the enemy's strategy.

One mark of a great soldier is that he fight on his own terms or fights not at all.