Well, seeing as I've asked this question and discussed it many times over the last quarter century I have to respectfully disagree in that many of the writers literally say the characters act, speak, etc. on their own.
This is not the case with me and with many writers who have to work hard, try various words, sentences, actions, etc all the time evaluating what would be 'in character' and then building it into the story.
I'm also quite familiar with the mental illness where people literally hear voices which again is not me, but is a condition of family. As best I can tell there is a fine line between the two. I suspect they are rooted in the same mental processes for those writers that do claim to literally have characters act and speak on their own.
In some ways I wish my characters were like this, it would certainly make the writing easier.
