"I think Father Christmas is real because the belief is real. The belief becomes the reality." — Matt Haig

If you sell the film rights to your book, it doesn't mean there will be a film. I have sold the rights to five books and had zero films made. Take the money and be thankful.

I think maths is the root of everything. If we understood every area of math, it would lead to improving our sense of science, physics, engineering, space travel... all those great things. Maths is a backbone for it.

Lots of children have had dark experiences, and if they're not having direct dark experiences, they are thinking about things and learning that life is fragile. You have to acknowledge that side of life to be able to then offer comfort and hope and goodwill.

Books should be right up there with exercise and diet as something that don't just entertain us but heal us. They tell us we are not alone and fix the pieces of us that can be shattered by reality. They are teachers, and they are friends, and we should never contemplate a world - or a life - without them.