Therefore, to estimate the enemy situation and to calculate distances and the degree of difficulty of the terrain so as to control victory are virtues of the superior general.
When, however, you have an enemy, then do not requite him good for evil: for that would shame him. Instead, prove that he did some good for you. And rather be angry than put to shame! And when you are cursed, I do not like it that you want to bless. Rather curse a little also! And if you are done a great injustice, then quickly add five small ones. Hideous to behold is he who is obsessed with an injustice.
However desperate the situation and circumstances, don't despair. When there is everything to fear, be unafraid. When surrounded by dangers, fear none of them. When without resources, depend on resourcefulness. When surprised, take the enemy by surprise.
When someone asked Abraham Lincoln, after he was elected president, what he was going to do about his enemies, he replied, "I am going to destroy them. I am going to make them my friends."