I can, therefore I am.
If you're going through hell, keep going.
To know oneself, one should assert oneself.
Either you run the day or the day runs you.
Be thine own palace, or the world's thy jail.
Only the educated are free.
Never complain and never explain.
Things do not happen. Things are made to happen.
To be a good loser is to learn how to win.
Be kind whenever possible. It is always possible.
A serious and good philosophical work could be written consisting entirely of jokes.