“Home is anywhere that you know all your friends and all your enemies.”

“Personal affection is a luxury you can have only after all your enemies are eliminated. Until then, everyone you love is a hostage, sapping your courage and corrupting your judgment.”

“It is easy to say that you can adopt the whole human race as your children, but it is not the same as living in a home with a child and shaping all you do to help him learn to be happy and whole and good. Don't live your life without ever holding a child in your arms, on your lap, in your home, and feeling a child's arms around you and hearing his voice in your ear and seeing his smile, given to you because you put it into your heart.”

“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.”

“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 only 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. I will devise the strategy of your army, and you will learn to be quick and discover what tricks the enemy has for you. Remember, boy. From now on the enemy is more clever than you. From now on the enemy is stronger than you. From now on you are always about to lose.”

“The only teacher that's worth anything to you is your enemy.”

“If you try and lose then it isn't your fault. But if you don't try and we lose, then it's all your fault.”