Quotes from Carl Sagan

Extraordinary claims require extraordinary evidence.

Who is more humble? The scientist who looks at the universe with an open mind and accepts whatever the universe has to teach us, or somebody who says everything in this book must be considered the literal truth and never mind the fallibility of all the human beings involved?

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 would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.

Imagination will often carry us to worlds that never were, but without it we go nowhere.

We are like butterflies who flutter for a day and think it is forever.

It pays to keep an open mind, but not so open your brains fall out.

The universe is a pretty big place. If it's just us, seems like an awful waste of space.

We can judge our progress by the courage of our questions and the depth of our answers, our willingness to embrace what is true rather than what feels good.

You're an interesting species. An interesting mix. You're capable of such beautiful dreams, and such horrible nightmares. You feel so lost, so cut off, so alone, only you're not. See, in all our searching, the only thing we've found that makes the emptiness bearable, is each other.

Books permit us to voyage through time, to tap the wisdom of our ancestors.

I don't want to believe. I want to know.

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But as much as I want to believe that, and despite the ancient and worldwide cultural traditions that assert an afterlife, I know of nothing to suggest that it is more than wishful thinking.

But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.

Two of the most energetic pro-lifers of all time were Hitler and Stalin — who immediately upon taking power criminalized previously legal abortions. Mussolini, Ceau?escu, and countless other nationalist dictators and tyrants have done likewise. Of course, this is not by itself a pro-choice argument, but it does alert us to the possibility that being against abortion may not always be part of a deep commitment to human life.

A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet.

If we continue to accumulate only power and not wisdom, we will surely destroy ourselves.

Books tap the wisdom of our species -- the greatest minds, the best teachers -- from all over the world and from all our history. And they're patient.

I can find in my undergraduate classes, bright students who do not know that the stars rise and set at night, or even that the Sun is a star.

We're in very bad trouble if we don't understand the planet we're trying to save.

Man is a transitional animal. He is not the climax of creation

It is far better to grasp the universe as it really is than to persist in delusion, however satisfying and reassuring.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark.

The universe seems neither benign nor hostile, merely indifferent.