“There is a surprising sentence about enigma in St. Augustine’s treatise, De trinitate. Nobody, says Augustine, can really understand the word “darkly” (for him, in aenigmate) in Paul’s text, “For now we see through a glass, darkly,” unless they have learned about tropes. For, Augustine adds, aenigma is a trope, a species of the genus allegory. He says this as a matter of course, not as some specialized or esoteric knowledge.”

—Eleanor Cook, Enigmas and Riddles in Literature, 2006.