http://www.theamericanconservative.com/dreher/story-dante-bibliotherapy/
Article articulates (funny never made the correlation between those two words before), essentially, fiction as "soft sell" while self-help is "hard sell" when it comes to encouraging behaviour.
"I won’t quote more from the Svoboda piece, from Aeon magazine,
which is excellent, but I will say this: she writes about how
neuroscience research indicates that stories have their particular
impact (over nonfictional information that our brains receive) because
of how the brain receives information embedded in a story. Briefly put, a
story activates parts of your brain that would have been activated had
you been going through the events of the story yourself. In other words,
the truths (or lies) embedded in a story become incarnate within us
because they are embedded in a story. This is not a metaphysical
proposition, but a biological one."