“When you have an enemy in your power, deprive him of the means of ever injuring you.”

“Hatred is love that's been injured. If you have hatred in your heart it means you have love in it also.”

“Someone that you have deprived of everything is no longer in your power. He is once again entirely free.”

“The primary thing when you take a sword in your hands is your intention to cut the enemy, whatever the means. Whenever you parry, hit, spring, strike or touch the enemy's cutting sword, you must cut the enemy in the same movement. It is essential to attain this. If you think only of hitting, springing, striking or touching the enemy, you will not be able actually to cut him.”

“An enemy, Ender Wiggin," whispered the old man. "I am your enemy, the first one you've ever had who was smarter than you. There is no teacher but the enemy. No one but the enemy will tell you what the enemy is going to do. No one but the enemy will ever teach you how to destroy and conquer. Only the enemy shows you where you are weak. Only the enemy tells you where he is strong. And the rules of the game are what you can do to him and what you can stop him from doing to you. I am your enemy from now on. From now on I am your teacher.”

“If you have an enemy, then learn and know your enemy, don't just be mad at him or her”