What is the first business of one who practices philosophy? To get rid of self-conceit. For it is impossible for anyone to begin to learn that which he thinks he already knows.
Authentic happiness is always independent of external conditions.
To the rational being only the irrational is unendurable, but the rational is endurable.
It is difficulties that show what men are.
Think of God oftener than you breathe.
Don't regard what anyone says of you, for this, after all, is no concern of yours.