Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.

Albert Einstein

Have the courage to use your own understanding.

Immanuel Kant

Man is condemned to be free.

Jean-Paul Sartre

Nothing in life is to be feared, it is only to be understood.

Marie Curie

If I have seen further, it is by standing on the shoulders of giants.

Isaac Newton

You can avoid reality, but you cannot avoid the consequences of avoiding reality.

Ayn Rand

Extraordinary claims require extraordinary evidence.

Carl Sagan

When I recall all that I have said, I envy the mute.

Seneca

Liberty not only means that the individual has both the opportunity and the burden of choice; it also means that he must bear the consequences of his actions and will receive praise or blame for them. Liberty and responsibility are inseparable.

Friedrich Hayek

I don't want you to think like me. I want you to think.

Unknown Author

If there were a party of those who aren't sure they're right, I'd belong to it.

Albert Camus

Democracy is the worst form of government, except for all the others.

Winston Churchill

The ego is not master in its own house.

Sigmund Freud

What does not kill me, makes me stronger.

Friedrich Nietzsche

There's real poetry in the real world. Science is the poetry of reality.

Richard Dawkins

Our minds evolved by natural selection to solve problems that were life and death matters to our ancestors, not to commune with correctness and answer any question we are capable of asking.

Steven Pinker

We are not thinking machines that feel, we are feeling machines that think.

António Damásio

An eye for an eye and the world goes blind.

Mahatma Gandhi

Justice without force is powerless, force without justice is tyrannical.

Blaise Pascal

The mind is not a vessel to be filled, but a fire to be kindled.

Plutarch

There are some people who would never have fallen in love if they had not heard there was such a thing.

François de La Rochefoucauld

What I know at sixty, I knew as well at twenty. Forty years of a long, a superfluous, labor of verification.

Emil Cioran

I cannot remember the books I've read any more than the meals I have eaten; even so, they have made me.

Ralph Waldo Emerson

Life is a tragedy when seen in close up, but a comedy in long shot.

Charlie Chaplin

I have never let my schooling interfere with my education.

Mark Twain

There is a crack in everything, that's how the light gets in.

Leonard Cohen

Life is what happens to you while you're busy making other plans.

John Lennon

The only way to get rid of a temptation is to yield to it.

Oscar Wilde

Resignation is a daily suicide.

Honoré de Balzac

What is best of all is utterly beyond your reach: not to be born, not to be, to be nothing.

Silenus