Carl Sagan

Absence of evidence is not evidence of absence.

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

No other planet in the solar system is a suitable home for human beings; it's this world or nothing. That's a very powerful perception.

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.

We are the representatives of the cosmos; we are an example of what hydrogen atoms can do, given 15 billion years of cosmic evolution.

There is a wide, yawning black infinity. In every direction, the extension is endless; the sensation of depth is overwhelming. And the darkness is immortal. Where light exists, it is pure, blazing, fierce; but light exists almost nowhere, and the blackness itself is also pure and blazing and fierce.

We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.

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

If you wish to make an apple pie from scratch, you must first invent the universe.

Extinction is the rule. Survival is the exception.

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

Science is a way of thinking much more than it is a body of knowledge.