I think about the characters I’ve created, and then I sit down and start typing and see what they will do. There’s a lot of subconscious thought that goes on. It amazes me to find out, a few chapters later, why I put someone in a certain place when I did. It’s spooky.
– Tom Clancy
We discussed this phenomenon once in the comments after one of my stories. I think it was “Nineteen Minutes.” And I was just this evening reading a chapter called “Not Without Laughter” in Langston Hughes’s autobiography The Big Sea. (Not Without Laughter is also the name of Hughes’s novel.) He said that in writing that novel he sometimes felt he had all the characters in the room with him, talking to him and advising him in drafts and revisions, as if they had wills of their own.