Never forget what a man says to you when he is angry.

When the character of a man is not clear to you, look at his friends.
Not to care for philosophy is to be a true philospher.
The mind is like a parachute. It doesn’t work unless it’s open.
The best mind-altering drug is truth.
Be wiser than other people if you can, but do not tell them so.
Never forget what a man says to you when he is angry.