We may see through the eyes of our parents, our children, our lovers, our supposed or real enemies, our ancestors, our descendants. We may realize what we want to happen - what kind of relationships, what kind of society we want to work toward, or work to prevent. In a stratified society all literature is engaged politically and morally, whether it's so perceived by the author or not. It will be so perceived by the readers it validates and by the readers it affronts. This doesn't mean that I think a novel or a poem can be judged by some utilitarian criterion.
Art is only partly rational.
It acts on all the levels of our brain and influences us through sounds and silences, through identification and imagery, through rhythms and chemistry. But as writers and readers, the literature we read makes us more or less sensitive to each other. Poems and novels tell us how we may expect to experience love and hatred, violence and peace, birth and death. They deeply influence what we expect to find as our love object, and what we expect to enjoy on the job or in bed, and what we think is okay for others to enjoy. They influence our daydreams and our fantasies and therefore what we believe other people offer s or are withholding from us.