If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds. Sailors on a becalmed sea, we sense the stirring of a breeze.

Somewhere, something incredible is waiting to be known.

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

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

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

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

The absence of evidence is not the evidence of absence.

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

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

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

You have to know the past to understand the present.

I was dead, then alive.Weeping, then laughing.The power of love came into me, and I became fierce like a lion, then tender like the evening star.

Education as the exercise of domination stimulates the credulity of the students.

Ideas are worthless if you can’t make them happen.

There's this sense of excitement because you invent and control the characters. You decide whether they live or die. I find this type of creative process tremendously stimulating.

As for the law of moral causation ('karma'): this is human justice dressed up as cosmic justice and then imputed to the impersonal workings of the natural world.

I defy any newcomer not to believe his or her publicity at the very beginning. It's only natural. At least it was for me.

Fiction is very important to me. It's what I do, it's what I do with my life.

We need to aim high - in the area of 20-25 percent - to create the urgent demand for new technologies, manufacturing plants and green jobs.

Syria is already in the grips of a civil war, unfortunately enough, and Egypt is moving in that direction. We would like to see the Egyptian people avoid this fate.

Writing a check separates a commitment from a conversation.