“Time is the friend of the wonderful business, the enemy of the mediocre.”
“It is easy enough to be friendly to one's friends. But to befriend the one who regards himself as your enemy is the quintessence of true religion. The other is mere business.”
“If this is how you treat your friends, no wonder you have so many enemies.”
“We ought so to behave to one another as to avoid making enemies of our friends, and at the same time to make friends of our enemies.”
“If the enemy of my enemy is my friend, then a friend of my enemy, is my enemy.”
“Every effect that one produces gives one an enemy. To be popular one must be a mediocrity.”