'Write the book you most long to read'

'this is the most important rule: write the book you most long to read. Writing a first novel takes so much effort, with such little promise of result or reward, that it must necessarily be a labour of love bordering on madness. So it was with my first novel, Roman Blood. I returned from my first visit to Rome with my imagination on fire. Having become addicted to crime fiction via Conan Doyle, what I most wanted to read was a book that in 1989 seemed not to exist: a murder mystery set in ancient Rome...'

'But to read that novel, I would have to write it myself. So I did. I suspect this is how first novels are most often (or at least most successfully) sparked: a reader experiences an overwhelming craving for a book that does not yet exist. Whether the story draws on the first-time author's own life and experiences or not doesn't matter, so long as it conveys a truth that transcends the cramped tenets of mere realism.'

Steven Saylor in the Guardian