I don't believe in souls. I think when we're doing something from the soul-like writing or composing music or painting, we're putting the sum of our life experiences and emotions into it by default. That is, if we aspire to be artful (whatever that means lol), then we'll try to express our views in our art in ways that are meaningful to us.
To me, if you're a good writer (blessed with good writing genes and practice), you'll write well, whether its coming from the soul or not. lol