From an interview with Toni Morrison in The Paris Review:
"Recently I was talking with a writer who described something she did whenever she moved to her writing table. I don't remember exactly what the gesture was -- there is something on her desk that she touches before she hits the computer keyboard -- but we began to talk about the rituals one goes through before beginning to write.
"I, at first, thought I didn't have a ritual, but then I remembered that I always get up and make a cup of coffee while it is still dark -- it must be dark -- and then I drink the coffee and watch the light come. And she said, well, that's a ritual. And I realized that for me, this ritual comprises my preparation to enter a space that I can only call nonsecular....
"Writers all devise ways to approach that place where they expect to make contact, where they become the conduit, or where they engage in this mysterious process. For me, light is the signal in the transition. It's not being in the light, it's being there before it arrives. It enables me, in some sense."