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.
I am sadly afraid that I must have done some wicked thing.
Pay attention to your enemies, for they are the first to discover your mistakes.
Not to unlearn what you have learned is the most necessary kind of learning.
The investigation of the meaning of words is the beginning of education.
We weed out the darnel from the corn and the unfit in war, but do not excuse evil men from the service of the state.