Carl Sagan

Better a painful truth than a comforting lie.

We are a way for the universe to know itself.

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

A book is made of paper, ink, and a little imagination.

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

The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pie were made in the interiors of collapsing stars. We are made of starstuff.

What an astonishing thing a book is. It's a flat object made of trees, with flexible parts on which are imprinted many dark squiggles. But it is still a world of strong emotion, of thought, of revelation.

The price of skepticism is the occasional loss of a great idea.

The truth may be puzzling. It may take some effort to grasp. It may be counterintuitive. It may contradict deeply held prejudices. It may not be easy to do what the truth demands. But none of that makes it false.

The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth.

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.

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to inaccessible times and places, and because he can be endowed with all sorts of powers and properties, I do not see how his non-existence can be demonstrated.

It is sometimes said that science is the enemy of religion. This is a common misconception. Science and religion are not enemies; they are simply different ways of looking at the world.

We are star stuff which has taken its destiny into its own hands.

Who are we? We are a collection of water and a few fundamental chemicals, but we are also a way for the universe to know itself.

I would love to believe that when I die I will live again, that some thinking, feeling, remembering part of me will continue. But 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.

The illegality of cannabis is outrageous, an impediment to full utilization of a drug which helps produce the serenity and insight, sensitivity and fellowship so desperately needed in this increasingly mad and dangerous world.

The Earth is like a tiny, fragile spaceship, and we are its crew.

We are a speck of dust in the cosmic ocean.

The greatest joy of science is discovery.