Why do we go to the movies, listen to or read stories, thumb through comic books? How is it that we can feel so deeply for characters we know are nothing but fictional?
I have much to say on this score. For the moment, ponder this.
Many different experiments show that from a very early age children have everyday ideas about psychology, biology, and physics. Their brains are equipped since birth with the capacity to construct a surprisingly quite accurate picture of the way their surrounding world and its inhabitants work.
The awareness of self and body and the awareness of our interconnected lives follow the same neural circuit and make possible our physiological resonance with others and our capacity for empathy.
The evidence from neurobiology confirms that the social informs directly the manner in which the brain develops its capacity to fully explore the world as it is (causality) and the way(s) it might be (counterfactually); how the social from birth through adulthood shapes the basic neurobiological and neurosociological mechanisms required for further and deeper knowledge of the world as it is and as it could be.
It is this could be that might offer us some insight into our fiction making and consuming activities.
I venture that fiction (and art generally) is simply a specific expression of this capacity to formulate or perceive relations of causality and counterfactual hypotheses, arguments, and thoughts generally.