I think I might just scrap all of my syllabus explanations regarding how I grade essays and short stories in my writing classes. I’ll just replace those with this passage from Umberto Eco’s The Name of the Rose:
For three things concur in creating beauty:
first of all integrity or perfection,
and for this reason we consider ugly
all incomplete things;
then proper proportion or consonance;
and finally clarity and light,
and in fact we call beautiful
those things of definite color.
— Adso, in The Name of the Rose by Umberto Eco
Fittingly, this comes straight out of medieval scholasticism (“I answer that”). It’s not surprising to find it echoed in Eco, given his intellectual background.