トマス・ド・クインシー「教訓詩について」より

"[…] and, therefore, the final object of a didactic poet is accomplished not by the didactic aspects of his poem, but directly in spite of them; the knowledge which emerges in such a poem, exists not for itself, but as an indirect occasion for the beauty, and also as a foil or a counter-agent for strengthening its expression; as a shadow by which the lights are brightened and realised."

John E. Jordan (ed.), De Quincey as Critic, Routledge & Kegan Paul, 1973, p. 146-152 ("On Didactic Poetry").