I can't help but wonder how that affects someones writing style. What I mean is, lets say you're writing a mystery novel about ohh...a serial murderer. You probably know what the detective has to do and probably isn't much of a problem. But developing the antagonist, the bad guy. I think we become our characters to some degree, and thus if we're writing about a murderer we'd have to let his murderous thought process into our own. Everything the bad, evil guy thinks, whether he's a demon, a murderer, rapist, cannibal, necromancer, or basically anything that would normally be unpalatable would have to be accepted and embraced to develop the character with those intentions. Not sure if I'm on the mark here, but does this affect your writing, and if so to what degree? Dean Koontz is a great example. In alot of his stories, we see the protagonist and the antagonists' side of the story. Thoughts?