Carl Sagan Quotes

The professed function of the nuclear weapons on each side is to prevent the other side from using their nuclear weapons. If that’s all it is, then we’ve gotta as: how many nuclear weapons do you need to do that?

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.

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

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

Don’t judge everyone else by your own limited experience.

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.

You probably don’t need more weapons than what’s required to destroy every city on earth. There’s only 2,300 cities. So, the United States, by that criteria, only needs 2,300 nuclear weapons – well, we’ve got more than 25,000!

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

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

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

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

I’ve written a number of books that have to do with the evolution of humans, human intelligence, human emotions.

We live on a mote of dust suspended in a sunbeam

You can’t convince a believer of anything; for their belief is not based on evidence, it’s based on a deep seated need to believe

You have to know the past to understand the present.

The brain is like a muscle. When it is in use we feel very good. Understanding is joyous.

We are the universe experiencing itself.