We must not contradict, but instruct him that contradicts us; for a madman is not cured by another running mad also.
The most useful piece of learning for the uses of life is to unlearn what is untrue.
There are only two people who can tell you the truth about yourself - an enemy who has lost his temper and a friend who loves you dearly.
As rust corrupts iron, so envy corrupts man.
I am sadly afraid that I must have done some wicked thing.
When brothers agree, no fortress is so strong as their common life.