The carbon dioxide concentration in the atmosphere is measured. It's uncontroversial. It's going up. We know that has a tendency to warm the atmosphere and we should be worried about that.

In future, children won't perceive the stars as mere twinkling points of light: they'll learn that each is a 'Sun', orbited by planets fully as interesting as those in our Solar system.

Absence of evidence is not evidence of absence.

It will not be humans who watch the sun's demise, six billion years from now. Any creatures that then exist will be as different from us as we are from bacteria or amoebae.

I think a few hundred years from now we'll start having the 'posthuman' era of different species.

It's better to read first rate science fiction than second rate science-it's a lot more fun, and no more likely to be wrong.

We need to broaden our sympathies both in space and time - and perceive ourselves as part of a long heritage, and stewards for an immense future.

Science is a part of culture. Indeed, it is the only truly global culture because protons and proteins are the same all over the world, and it's the one culture we can all share.

I hope that by 2050 the entire solar system will have been explored and mapped by flotillas of tiny robotic craft.

I'm not myself religious but have no wish to insult or denigrate those who are.

Crucial to science education is hands-on involvement: showing, not just telling; real experiments and field trips and not just "virtual reality".

I paid, got up, walkedto the door, openedit.I heard the mansay, "that guy'snuts."out on the street Iwalked northfeelingcuriouslyhonored.

No need for miracles to do the impossible if we have beliefs, will and insistence

Don't worry about what you're writing or whether it's good or even whether it makes sense.

The fact that people who create are good workers tends to be lost.

Remind yourself: you are not your thoughts or feelings

I like to dissect girls. Did you know I'm utterly insane?

My love is for acting not money, so I only take on roles that I find challenging, in stories I find interesting.

Often times when you face such an overwhelming challenge as global climate change, it can be somewhat daunting - it's kind of like trying to lose weight, which I know something about.

I hadn't learned yet that everybody's locked up some way or other. That's how life is we're all imprisoned by something.

Honestly, folks, I think my brain is broken.