Reviewing what you have learned and learning anew, you are fit to be a teacher.

You will never know how sharp a sword is unless it's drawn from its sheath

An angry man is full of poison.

The perfecting of one's self is the fundamental base of all progress and all moral development.

The only people who cannot change are the most wise and the most stupid.

When you have faults, do not fear to abandon them.

The man who is master of himself drinks gravely and wisely.