And when the universe has finished exploding all the stars will slow down, like a ball that has been thrown into the air, and they will come to a halt and they will all begin to fall towards the centre of the universe again. And then there will be nothing to stop us seeing all the stars in the world because they will all be moving towards us, gradually faster and faster, and we will know that the world is going to end soon because when we look up into the sky at night there will be no darkness, just the blazing light of billions and billions of stars, all falling.

Prime numbers are what is left when you have taken all the patterns away. I think prime numbers are like life. They are very logical but you could never work out the rules, even if you spent all your time thinking about them.

Bore children, and they stop reading. There's no room for self-indulgence or showing off or setting the scene.

Find the extraordinary inside the ordinary.

I started writing books for children because I could illustrate them myself and because, in my innocence, I thought they'd be easier.

Appalling things can happen to children. And even a happy childhood is filled with sadnesses.

Then he asked if I didn’t like things changing. And I said I wouldn’t mind things changing if I became an astronaut, for example, which is one of the biggest changes you can imagine, apart from becoming a girl or dying.