The Chilean novelist Isabel Allende says there's no such thing as writer's block, you just need to live a bit more. I try to bear that in mind.

In the course of writing a book I'll produce loads of pieces of paper to help the novel itself. Diagrams, charts, family trees. And at the end of each book I'll pack it all away. It takes me a while to do it - it's like a relationship that way; there's a period of letting - go, of grief, in a way - but then I box it up, label it, and put it in the attic.

Why isn't life better designed so it warns you when terrible things are about to happen?

For a while I used to listen to those whispers about babies costing you books, and Cyril Connolly's loathsome quote that "There is no more somber enemy of good art than the pram in the hall." But it's rubbish. Absolute rubbish. A huge amount of your work is done when you're not at your desk. Knotty problems that you need your unconscious to solve. So it can be helpful to walk away and focus on other things and it can be helpful to be a bit harassed in your daily life, to be hungry for time to write.

I think it's dangerous to have lots of time on your hands as a writer. Time to pursue every little alleyway, to follow every single whim. I feel I've done my best writing when I'm stretched for time, when you're most pressured.

As other authors have realized, heat can have a strange effect on us, can cause odd chemical reactions in the brain. Heat can bring out secrets; it can change people's personalities.

I met a retired police detective. And he said to me that the interesting thing about heatwaves, from a police perspective, is that the number of people who just walk out of their lives when the weather gets unbearable is astronomic. He said the police prepare themselves for it - for a huge rise in the instances of missing persons. People choose to disappear when it's hot. It was fascinating.