Experience keeps a dear school, but fools will learn in no other.
The only real mistake is the one from which we learn nothing.
A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
I think, therefore I am.
Boredom is the root of all evil - the despairing refusal to be oneself.
Think globally, act locally.
When you learn, teach, when you get, give.
If you have no problems, then you have no clue to what is going.
Accuracy is the twin brother of honesty; inaccuracy, of dishonesty.
The only limit to our realization of tomorrow will be our doubts of today.
Things which matter most must never be at the mercy of things which matter least.
It is a cliche that most cliches are true, but then like most cliches, that cliche is untrue.
Madame, all stories, if continued far enough, end in death, and he is no true-story teller who would keep that from you.
Every act of creation is first an act of destruction.
Those who cannot work with their hearts achieve but a hollow, half-hearted success that breeds bitterness all around.
Wisdom is not the product of schooling, but of the lifelong attempt to acquire it.
If we don't believe in freedom of expression for people we despise, we don't believe in it at all.
No man has any natural authority over his fellow men.
If you are neutral in situations of injustice, you have chosen the side of the oppressor.
When you judge another, you do not define them, you define yourself.
What's done can't be undone.