If the spectrum linking everyday depression to Major Depression sometimes hinders understanding of it, it also offers an opportunity for empathy. Because almost everyone, at some point, experiences feelings of sadness, of hopelessness, of emptiness, not to mention lethargy and irritability.

I wasn't one of those kids who grew up wanting to write or who read a particular book and thought: 'I want to do that!' I always told stories and wrote them down, but I never thought writing was a career path, even though, clearly, someone was writing the books and newspapers and magazines.

When I was really young, I wanted to grow up and be the sun. Which shows an early penchant for ambition or narcissism or grandiosity or delusion - all of which are bellwethers for becoming a writer.

It's not that we like sad movies that make us feel like, 'Oh, my God, what a bummer.' We like emotionally moving experiences. It's nothing new. It's catharsis. It goes back to the Greeks.