Prose on certain occasions can bear a great deal of poetry on the other hand, poetry sinks and swoons under a moderate weight of prose.

Landor draws a sharp distinction between the capacities of prose and poetry. Prose, he suggests, is structurally resilient: it can absorb poetic devices—imagery, rhythm, metaphor—without losing its footing, and may even be enriched by them. Poetry, by contrast, is more fragile in its formal economy; when weighed down with prosaic exposition, explanation, or discursive argument, it loses the very qualities that make it poetry (compression, music, intensity) and collapses into dullness. The remark doubles as a practical aesthetic rule: poetic effects can invigorate prose, but prose-like padding is a common way for verse to fail.