Carl Sagan

Where we have strong emotions, we're liable to fool ourselves.

I maintain there is much more wonder in science than in pseudoscience. And in addition, to whatever measure this term has any meaning, science has the additional virtue, and it is not an inconsiderable one, of being true.

A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism.

Anyone who's ever significantly changed the course of humanity has either been a Crackpot, a Heretic, or a Dissident. In the case of Albert Einstein, he was all three!

One glance at a book and you hear the voice of another person, perhaps someone dead for 1,000 years. To read is to voyage through time.

Absence of evidence is not evidence of absence.

In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness.

The first priest was the first rogue who met the first fool.

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.

All of the books in the world contain no more information than is broadcast as video in a single large American city in a single year. Not all bits have equal value.

It is of interest to note that while some dolphins are reported to have learned English -- up to fifty words used in correct context -- no human being has been reported to have learned dolphinese.

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.

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 someting like that happened in politics or religion.

Skeptical scrutiny is the means, in both science and religion, by which deep insights can be winnowed from deep nonsense.

The universe is not required to be in perfect harmony with human ambition.

Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people.

If you want to bake an apple pie from scratch, you must first create the Universe.

If you want to make an apple pie from scratch, you must first create the universe.

The universe seems neither benign nor hostile, merely indifferent.

If we long to believe that the stars rise and set for us, that we are the reason there is a Universe, does science do us a disservice in deflating our conceits?

Personally, I would be delighted if there were a life after death, especially if it permitted me to continue to learn about this world and others, if it gave me a chance to discover how history turns out.

Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science?

Somewhere, something incredible is waiting to be known.

When you make the finding yourself - even if you're the last person on Earth to see the light - you'll never forget it.

Science is not only compatible with spirituality; it is a profound source of spirituality.

For small creatures such as we the vastness is bearable only through love.

Extraordinary claims require extraordinary proof.

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

If it can be destroyed by the truth, it deserves to be destroyed by the truth.

Just 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.