"It is lawful to swear by God, provided it be for a just cause."

"It is better to illuminate than merely to shine, to deliver to others contemplated truths than merely to contemplate."

"The purpose of human law is to lead men to virtue, not suddenly, but gradually."

"In procreation the man is active, the woman is passive."

"It is lawful to kill a man who is an enemy of the commonwealth, even if he is not actually committing a crime."