“Grip the nettle firmly and it will become a stick with which to beat your enemy.”

“Self-education is, I firmly believe, the only kind of education there is.”

“You don't beat refusal to believe in a frontal attack.”

“A wall is happy when it is well designed, when it rests firmly on its foundation, when its symmetry balances its part and produces no unpleasant stresses. Good design can be worked out on the mathematical principles of mechanics.”

“These are facts which, with the self-evident proposition that no being can create another being superior to itself, smashes your silly hypothesis to nothing.”

“It is the obvious which is so difficult to see most of the time. People say 'It's as plain as the nose on your face.' But how much of the nose on your face can you see, unless someone holds a mirror up to you?”

“Do not forget that a traitor within our ranks, known to us, can do more harm to the enemy than a loyal man can do good to us.”