Carl Sagan

The Earth is a very small stage in a vast cosmic arena.

There is a poignancy that is almost unbearable. It is the only home we've ever known.

For all our failings, despite our limitations and imperfections, we are part of something much larger than ourselves.

We have not been as careful as we might have been.

The universe seems neither benign nor hostile, merely indifferent.

An extraterrestrial being, newly arrived on Earth — scrutinizing the accumulated knowledge of our species — would no doubt conclude that we are obsessed with sex.

The brain is a very big place in a very small space.

We make our world significant by the courage of our questions and the depth of our answers.

What an astonishing thing a book is. It's a flat object made of parts of a tree with flexible parts on which are imprinted many dark squiggles. But it is a port into the universe of the imagination.

If we are to survive, we must have a new vision of the world.

One of the saddest lessons of history is this: If we've been bamboozled long enough, we tend to reject any evidence of the bamboozle. We're no longer interested in finding out the truth. The bamboozle has captured us. It's simply too painful to acknowledge, even to ourselves, that we've been taken. Once you give a charlatan power over you, you almost never get it back.

A book is made of paper, ink, and a little glue. It is a thing of wood and cloth and thread. But it is also a thing of wonder.

The cosmos is within us. We are made of star-stuff. We are a way for the universe to know itself.

In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they actually change their minds and you never hear that old view from them again.

The cure for a fallacious argument is a better argument, not the suppression of ideas.

If we are to survive, we must have a new vision of the world, a vision that is both cosmic and human.

We have been given a gift of immense value. We have been given the Earth. We must be good stewards of it.

The cosmos is full of wonders, and we are just beginning to explore them.

Our loyalties are to the species and the planet. We speak for Earth.

The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we wish to believe. But none of that makes it false.