Comment by mherdeg

My two reference materials on this topic are:

(1) Bruce McAllister's symbolism survey - a 16 year old high school student straight-up asked bestselling authors whether they put symbolism in their work, with various replies - https://www.theparisreview.org/blog/2011/12/05/document-the-...

(2) Ogden Nash's "Very Like A Whale" - Nash wrote a short, rhyming essay about how frustrating it was that authors sometimes try to use rhetorical techniques to convey meaning obliquely - http://www.people.fas.harvard.edu/~pahk/poems/021221.html . It always makes me giggle.