Lucius Annaeus Seneca was a Roman Stoic philosopher, statesman, dramatist, and in one work humorist, of the Silver Age of Latin literature... (wikipedia)
One of the most beautiful qualities of true friendship is to understand and to be understood.
True happiness is... to enjoy the present, without anxious dependence upon the future.
A happy life is one which is in accordance with its own nature.
Brave men rejoice in adversity, just as brave soldiers triumph in war.
A physician is not angry at the intemperance of a mad patient, nor does he take it ill to be railed at by a man in fever. Just so should a wise man treat all mankind, as a physician does his patient, and look upon them only as sick and extravagant.