Life is bearable even when it's unbearable: that is what's so terrible, that is the unbearable thing about it.

It's this thing that's going on all the time - aging. Paul Auster quotes the poet George Opren on growing old: "What a strange thing to happen to a little boy." Which I think is so profound.

Nicholson Baker talks about the way in which the most successful nonfiction books are those that can be boiled down into an argument so that everybody can wade in with an opinion without having to undergo the inconvenience of having to read the book itself. The more you can condense it, the better.

I want to stress, this is the experience-growing up in a working-class family-that defined me and continues to define me. It's the core of my being. And it explains, incidentally, a good deal about my love of America.

I would hope that nothing that I write would ever seem earnest because I subscribe absolutely to Franz Nietzsche's claim when he says, "Ah, earnestness, the sure sign of a slow mind." Earnest people are always a bit on the thick side in my experience.

I think, about the distinction between fiction and nonfiction. Fiction is not really about anything: it is what it is. But nonfiction - and you see this particularly with something like the BBC Samuel Johnson Prize for Non-Fiction - nonfiction we define in relation to what it's about. So, Stalingrad by Antony Beevor. It's "about" Stalingrad. Or, here's a book by Claire Tomalin: it's "about" Charles Dickens.

What I'm really interested in, as a reader and as a writer, is the idea of the nonfiction book that is not defined by its content, by its "about"-ness. Where you read it irrespective of whether you're interested in the subject.