Those who know, do. Those that understand, teach.
Not everything that can be counted counts, and not everything that counts can be counted.
Moderation in temper is always a virtue; but moderation in principle is always a vice.
One never notices what has been done; one can only see what remains to be done.
The road of excess leads to the palace of wisdom.
A person who spends more than he earns is a fool
A man may imagine things that are false, but he can only understand things that are true.
Courage is resistance to fear, mastery of fear - not absence of fear.
Compassion is the basis of morality.
Each problem that I solved became a rule which served afterwards to solve other problems.
The place where you made your stand never mattered. Only that you were there...and still on your feet.
To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact
Intelligence is the ability to adapt to change.
Respect yourself if you would have others respect you.
When prosperity comes, do not use all of it.
Honesty is the first chapter in the book of wisdom.
The future is uncertain but the end is always near.
If I speak of myself in different ways, that is because I look at myself in different ways.
Medicine heals diseases of the body, wisdom frees the soul from passions.
The greatest minds are capable of the greatest vices as well as of the greatest virtues.
If you don't stand for something you will fall for anything.